Kohler ultralight engine

[@davidgoddard2599]

don't sell yourself short this was a ggreat video thanks for sharing

[@Brough1111]

Agree

[@edrosenberger6947]

Sounds much better than any of the 2-cycle engines. I'm about to start building an ultralight and was looking at the Honda "V" 23 HP engines which have ball bearing supported crankshafts. I started looking at the Kohler engines but none of them had ball bearings to take the belt (or chain) loads. Perhaps your larger engine does.....I didn't know Kohler made one that large and I'll check it out as well. I like how your brain works....you've paved the way for other UL people like me that want to fly with something better than 2-cycle screaming gas guzzlers and a well designed UL will fly well with 35 hp engine that weighs around 85 lb. You have been very generous with your hard earned knowledge. I have read your answers to commenters and which shed more light on this engine. Things like the aluminum flywheel and jetting of the original carb and perhaps other things are questions for me right now and I would pay for your answers.....there may be others' that feel the same way. At any rate, thank you Ron for this video....

[@edrosenberger6947]

I just found your page two for this engine mod. Very nicely designed installation Ron....thank you for this extra information!

[@garybucher6824]

Just curious if you have built anything yet?

[@JOHNDANIEL1]

We put a Harbor Freight 23 horse v-twin in a boat, Replaced a 3 cylinder in-out board still running perfect in last 2 years.

[@bruceruttan60]

Super video and the kind of thinking I like. Light, cheap and very strong.

[@georgejordan9516]

I bet that runs real cool with all that air running past it

[@raydreamer7566]

Great video - just great. You made such a simple reduction drive. I can see your chain just floating in your video.

[@chadharrison8653]

Great info, sometimes you can just tell by the way a person speaks if they know what they are talking about or not and you sir are one of those people that knows his stuff. Nice in-depth explanation of your conversion. Did anyone ever tell you that you could do voice-overs for John Goodman?

[@chriscunningham6362]

Sounds great and seems to be solid as a rock! Nice Job!

[@mr1rapid]

I would like to add: the 50 pitch chain is probably the most common size motorcycle chain used on bikes from 250cc - 750+cc. commonly run on bikes over 60 hp. Good size for that engine and application......should last a long time. A plus is the chain can be replaced without taking the reduction unit apart. Great video!

[@RonBesse]

mr1rapid Hi mr1 rapid, It's wonderful to hear from a motorcycle person.Thank you so much for commenting. We've been using chain drive on everything for well over 100 years now. I'm totally blown away at the comments I've been getting from some of the airplane people. I thought I would have gotten a more educated response from them. Most seem to respond from things they have been told or heard ( superstition and folklore) rather than from personal hands on experience from design and build. Not all though, most ultralight people have been totally supportive of this project, and my many thanks to them. I've had this setup for over 7 years now and had the engine completely apart twice with NO signs of wear at all. The same with the chain as you can imagine, only the oxide finish on the sprocket and chain contact point. I had a Kawasaki 420 KX back in the early 1980's and through endless hours of sand, mud, water, rocks, coal dust, everything and maybe oiled the chain twice. If that. Never even thought about it. I have never broke a chain ever on the mini bikes, dirt bikes, go karts, street bikes, airplanes, timing chains in my cars and trucks, bicycles, etc.... Done 6000 rpm hole shots on street bikes with three gear wheelies, and nothing. Never broke a chain. It's like some of the airplane people are setting on the edge of their seats wanting this to fail to say, see I told you so, that's what LeRoy down the street said, that chain drives will not work. LeRoy is a fictitious person in the Stits aircraft covering supply manual that has never built anything but offers his uneducated opinion on every step of the recovering process of an airplane in the manual. Now I know why the company put LeRoy in their manual. Too funny. Thanks again for commenting, Sincerely, Ron Besse.

[@mr1rapid]

Blankbiplane Most recently I built a Honda ST1100 V4 100 hp with 6-speed transmission and clutch and 530 chain reduction for a Sonnex. We have not taken to the air due to health/money issues of my partner. Should be very smooth. The reduction from trans to prop is 1:1 with 6 gears, clutch and built in cush drive should be good. You mentioned chain slap. If you are concerned you might consider something like a later Harley Sportster , very simple spring loaded nylon shoe on the primary chain. I have 4 slideshows on youtube of my Affordaplane (Affordaplane build). I'm considering the Kohler as a swap. Better torque and sounds great.

[@marvinblankinchip2535]

Blankbiplane ... Didn't the Wright brothers use chains? lol. You have done a good, really thought out job

[@janettemolina7948]

Las cadenas se utilizan sobretodo para baja rotacion,son ruidosas,pierden la lubricacion en altas rpm,es mejor un sistema de correa de goma que a la vez funciona como amortiguador de voibraciones,buen trabajo,buena suerte. The chains are used especially for low rotation, they are noisy, they lose lubrication at high rpm, a rubber belt system that works as a shock absorber, good work.

[@lookout816]

Sound kinda like John Goodman, great video!

[@CrusaderSports250]

Oh to live in the States where this sort of innovation is at least allowed, here in Blighty the CAA would have you against the wall for just thinking about something like this, more power to your innovations sir!..

[@richardlemieux7561]

Thanks you for the video, it gave me alot to think about

[@robertwood3970]

Thanks for the reply, I enjoy your channel.

[@cartmanrlsusall]

Ill follow how this interesting project goes.i heard the baxklash from a prop is why rotax used their elastomeric reduction drives chains allegedly transmits it back into the engine causing problems

[@h7oslo]

Good presentation! Thanks for taking the time to make the vid for us. rc

[@AlaskanOutdoorsman]

Good video. Trying to learn about building redrives, your video helped. Thanks for posting.

[@gwwchem]

Man what a super informative video. Obviously you are far more knowledgeable than I am and your explanations are great. Hopefully you have some of design covered by patents. You are extremely generous with the information you have worked so hard to develop. Would you be interested in building a trike with this engine for me?

[@pedrojm2003]

Thanks is the best info I got thru all the web you’re a pro it help me ton in my project thanks again

[@rkhyden1950]

Great video. Thank you for teaching us a lot of good information.

[@Dur21]

Very nice. Thinking out of the box great.

[@louisramirez3128]

I'm seein the chain slappin silly back there . . . I'm STILL watchin though.

[@akio2589]

Yes, I know this is an old video, I donno if you even still have the thing, but a few improvements to be made: 1. YOU NEED MORE MOTOR MOUNTS. I would NOT have all that stress on the bottom crank case mounts if I were you. It's not like they're made from billet. They're cast and not super strong. That engine flopping around like that AND the thrust from the prop is a bad combo on those mounts alone. 2. You should really put a spring loaded tensioner on that chain, a guide rail, something to take up the slop when it's under load. Be a bad day if that came off there mid-flight. 3. Good God, man! Put some guards of some type on there! I know you're trying to save weight, but some fiberglass tent poles and some chicken wire don't weigh that much. No reason to compromise safety. Otherwise, I like it.

[@zackhamilton7421]

akio2589 you have my same thought about the engine mounting. I believe a top mount to either or both cylinder heads would be a must after that run-up on camera. There is a little chain slap but the teeth on those sprockets are so long that it is impossible for the chain to jump off the track unless something fails, unlike a belt drive. When belt and pulleys are off just a small amount it's easy for a belt to jump alignment. So in conclusion, the use of a top motor mount would be much safer due to the flex I witnessed in the video. If the case were to give, it could come forward and contact the pilot in a gruesome way...

[@carmelpule6954]

Considering the main plate on the reduction gearbox attached to the engine, I would say the weight of the top part, the fact that there is a hole in it for the shaft and the fact that the engine is vibrating, there at the upper point engine attachment would be subjected to a movement and so fatigue in a horizontal line manner. I would have thought that adding or continuing downwards the two modified C beam holding the prop shaft would have reinforced the plate a little better. Looks like a good sturdy engine, and I do agree with you regarding the overheating and the mixture, though one cannot take it too far. I feel that with my type of applications, I prefer to have a slightly rich mixture where the burning takes place slowly hence a slow expansion and a push on the piston, rather than a fast explosion of a lean mixture where a faster impulse is given to the piston. I do like to operate my engines in a sort of smooth graceful manner rather than try to make it slave away to get the most competitive power out of it.

[@Daaremikkel]

LOP...an interesting subject. www.avweb.com/blogs/insider/Lean-of-Peak-Ignorance-Returns-Or-Maybe-It-Never-Left-224794-1.html

[@benheatherman2839]

The only thing i'm not too sure about is at 7:58 I see some red RTV silicone gasket maker where your custom intake pipe meets the stock intake manifold. I can tell you from personal experience that RTV really doesn't make very good intake gaskets as the gasoline gradually softens the RTV (unless it's Hondabond which is black) and eventually I've always wound up getting vacumm leaks. I can't tell if there's a gasket in there but if there isn't I'd highly recommend getting a proper paper gasket.

[@phoneticau]

I love it, Im taking away lots of ideas for a hovercraft project

[@dynomania]

Oh sorry just read comments around 40 HP excellent.

[@jhnfrsn]

Hey I would love to have details on how to do the conversion and parts your using. Thanks

[@xeriotti]

Hi Ron!!! How that chain reduction drive behaved thru the years??? Looks awesome and seem to be really strong... Pros and Cons? would you reccommend going that way? or choosing a belt drive?

[@billyvray]

My man dropped this great vid, then vanished. I'd still love to get your info on this redrive!

[@vg23air]

get an ace aviation redrive, with toothed belt

[@billyvray]

@@vg23air No doubt. I just like seeing what people have done/learned even if it's "what not to do".

[@TimDonk]

Anything new on this? Info on the subject is very sparse, but this video has me leaning hard toward this motor for an Affordaplane build.

[@canoe365]

I too have heard about dangerous harmonics between the crankshaft and the propeller and how chains don't allow slippage or shock absorption to protect the crankshaft. But you can't argue with results. So your chain and sprockets are holding up OK? Maybe that small amount of slack in the chain is allowing any harmonics to damp out. I would like to hear how things are doing after you have a hundred or more hours on it. Does the Kohler have a ball bearing on the PTO side of the crankshaft? I'm looking at the Predator 670 cc V-twin, it doesn't have ball bearings on the PTO side of the crankshaft. But neither does my son's 20-year old Lexus with 1/4 million miles on it.

[@jimmcnabb9433]

I just discovered your video and I am intrigued with your PRSU which seem quite robust. Your description showed the double ball bearing supporting the propeller shaft but you didn't discuss the method fro reacting the thrust from the propeller. I could not discern a thrust bearing from the video and was wondering what method you used?

[@RonBesse]

They were the deep groove ball bearings that also work for a thrust bearing. I used a belt redrive from Valley Engineering (first generation ) on my biplane. 2332cc type 1 VW that produced 150hp @ 4800rpm. That reduction drive just used a single deep grooved bearing. Never had any issues with it. I used two of these type bearings in that chain drive to take any wobble out of the system. Really wasn't needed. I just thinking safety incase one set came apart. I wouldn't loose the propeller. It only had about 5-6 thousandth inch play in and out. Ran it for 7 years before making that video. Same engine was in my Fokker EIII Ultralight before building the flexwing trike. I never had to do anything at all to both planes. Very reliable system. Unlike the Vittorazi Moster 185, I fly in my paramotor now. LOL Thanks for watching. Most Sincerely, Ron.😎

[@robertwood3970]

Aren't you worried about the harmonic vibration your engine will see using the chain drive? Also the chain will make a lot of unwanted noise. Valley Engineering makes a belt set up that helps dampen out the harmonic vibration.

[@RonBesse]

Hi Robert, If I take off the propeller and run the engine up, there is no vibration to speak of, with or without the redrive. All parts are already balanced to begin with. All vibrations will come from the propeller not being balanced. I have bought and used a great number of propellers over the years from a number of manufactures and have yet to just pull one out of the box and slap it on and go. I even had a 72" three blade Warp-drive that had to be balanced and that was well over $1000 propeller back then. As for as noise, this is a 725 cc engine and is just like a twin cylinder motorcycle. The last thing I can hear on a 725 cc engine setting just behind me at 4500 rpm and the muffler and 60" four blade propeller at arms reach is the sound of that little chain. Just remember the cars we drive have chains driving the cam shafts in the engines for 100,000's of miles with never a thought of fail or vibrations to the engine. Even most of the 4 cylinder engines in cars today have went back to chains from belt drives that failed back in the 80's and 90's. Most Motorcycles are chain driven. This build was not to say that chain or belt is the only way to go. It would have been just as cool to put a Rotax B-Gear box on it and call it a day. I was trying to keep the whole build under 254 lbs for a really legal 103 ultralight with a low costing 4-cycle engine. This redrive weighs 14 lbs total. I used the 1st generation Valley Engineering redrive on my Biplane and loved it. It used 3 timing belts that could hold up to the 150 hp, that I was getting out of my 2332 cc type 1 VW running a 350 cfm Holley carb turning 4800 rpm. They went to the single v-belt now with a revers direction tensioner, so that they could machine them out their selves. 1st gen in my opinion was stronger and last longer and lighter, but cost more to make. I also, made two belt drives for this before the chain drive. They just weigh so much more to get a belt that will hold up. No difference in vibrations between the belt or chain. Kevin Armstrong in the UK (see KZbin) also runs a very nice belt drive, and I think he sells them for around $425 US. I did go back to using the stock Kohler single carburetor. It does have a removable jet just behind the electric fuel shut off solenoid. The idle is so much more smooth and very responsive and will run at full 5000 rpm's with no issues to heat. Not worth switching to the Bings or Mikuni or Solex carbs. I also ran this engine in the Folker E III, that I designed, built, and flown before using it in this build. This setup has been used for over seven years now with nothing going wrong. I also have recently sold the trike, so I can't give much more to any updates. Also, Midwest Super Cub, came out with a stroker kit for this engine that gives 10 lbs more torque without weight gain. Very cool. Could run lower rpm to get same 40 hp. Longer engine life. Hope this helps some, and thinks for commenting. Most Sincerely, Ron

[@markmcelrea2106]

Blankbiplane if you stick the striker package in and stay with the rpm you were using what kind of power do you think it might put out and also I wouldn’t mind picking your head more about jetting when you have time very informative and helpful video thanks

[@robertwood3970]

@@RonBesse Do you have any experience turbocharging the Kohler engines?

[@45llamas]

I think would be great to use a 450cc dirt bike engine (Japanese bikes of course), it has almost 50hp that is more hp than the engine you are using and weights nothing also it has the 5 speed transmission on it so you can play with it and find which gear is the best for your prop, very reliable engines, if rebuild properly. To conect it to the prop just use the same bearings you used but with an drive shaft

[@mrromantimothy]

I would feel more comfortable with a bar behind my shoulders and head other than that that is a pretty cool design

[@hadleymanmusic]

Awesome monoplane!

[@flytoday]

Be good to see a video of what that chain is doing under power

[@577buttfan]

It's job.

[@maxhammontree3169]

Holy shit! It starts at 25:30.

[@jackfrost2146]

My thoughts aren't backed up by any science or calculations, but to me there seems to be excessive unsupported crankshaft with the sprocket so far out, maybe leading to metal fatigue on the shaft, also putting much higher loading on the engine bearing.

[@stolaircraftsuyanto9728]

hello sir, I see the gearbox using a chain. is that strong? I think for a Honda engine fit 1.5L 130hp using a gearbox like you have. is it strong?

[@mrromantimothy]

I'm not sure about how much weight it would add but for a belt drive I would have twin belts for the double redundancy you need for an aircraft

[@5019ant]

Everything looks awesome but wouldn't the intake flow better with a sweeping 90* elbow than that straight sharp welded 90* I don't know just thinking about the flow smooth is always better !! Real nice though beautiful job good luck and be safe !!

[@rkwill100]

strongly suggest adding a bearing at the end of the crankshaft to support the side load from the rest of the reduction drive and prop. I cannot tell exactly what the details are on the drive chain, but it looks like the drive pulley is a bit small diameter for the chain. the engine should be mounted by 'lord' mounts or 'berry' mounts, NOT hard mounted to the frame. This is to isolate the engine vibration from the frame. the battery box is very nice, do need to 1) pad the battery so the vibration does not get to it and a hold down strap so it cannot bounce around the PSRU chain needs some kind of lubrication system other wise it will have a very short life what is the 'weight and loading'? I.E. with both a full and empty fuel tank, and you sitting in the seat, does it properly hang with the nose wheel just a few inches above off the ground when the mains are on the ground?

[@marvinblankinchip2535]

rkwill100 ... I wonder if at all some point you might have received a small clue that this man is not a total idiot. He is not a novice, he has built other successful experimental aircraft and appears to have a good grasp of what it takes to build a safe airworthy craft. Most of the points that you mentioned were addressed on the video or have been addressed here in the comments. Please note he motion of the engine on start up. I'll guarantee you there are shock mounts there either Berry or Lord type. I'm a little confused. I haven't decided if you've made constructive criticism or just being a condescending troll.

[@anacarrillo8328]

Its been a year, I wonder how this has been working? You make it sound durable and safe. I know that chain is much cheaper than belts. I am concerned when I see NO ONE using chain drive. Years ago, I remember the UL folks pretty much decided to chains weren't good. Is it because they weren't doing it correctly? I for one am very interested in how this experiment goes. How large an engine could be reduction geared with chain?

[@RonBesse]

Ana Carrillo Hi Ana, The simple of this is, type in the below search in your KZbin and check out those smaller chains on those turbo and NOS powered drag bike. The real question is how much power until belts don't hold up.Pro Street 200mph No Wheelie Bar Drag Bikes!

[@kswift6614]

Ron con you do a video on carburetor jetting to get air cooled motors running cooler

[@readmore7180]

Really nice setup. I'm struggling to understand something with what I see being done to these engines, there is probably a good reason that I'm overlooking . That thing is. I see everyone taking out the governors so the engine revs higher but then putting on reduction drives to then slow it back down again, why not just leave the governor off and do direct drive to the prop?

[@unhippy1]

up to a certain point rpm's = horsepower......more rev's = power ..... but the prop is RPM limited or the blade tips break the speed of sound (hell noisy and rather inefficient) so you need to gear it down again to keep the HP AND have the prop tips stay under the speed of sound

[@readmore7180]

yeah I thought that might be the case, but then thought you can up power without upping rpm. Think the best thing for me to do is test it myself and see how much real world difference there is .

[@terracethornhill]

I love the idea of a 4 cycle ultralight, but part of what appeals to me is the long term reliability of 4 strokes. I think that must be reduced somewhat by the high rpm you're using, most actual aircraft engines only turn about 2 grand. I would be interested to see if that motor could be made to perform at stock rpm, say a take off rpm of 3600, that's the speed of a generator, so stress would be kept to a minimum. One thing that seriously concerns me about your setup is the chain drive. Chains get dicey at high rpms, I don't think I've ever seen an open single chain drive used on an aircraft before and that's probably for a good reason. The way I see it lashing around, I'd bet money that it will fail abruptly at some point, a toothed belt drive would be a lot safer. Good luck and best wishes.

[@mr1rapid]

TerraceThornhill I have seen an LSA High wing pusher running a Honda CB 650 mounted low behind the pilot air cooled the 530 chain must be 8ft long with no tensioner for running slack. He has 5 speeds to select from but sounds like he only uses 2 or three. You wouldn't believe the performance of that plane and he says has never changed the chain in 6 years. I have no idea of flight hours but he's all around south Mississippi and Louisiana all the fly-ins. There are even some motorcycle engine powered ultralights here on You Tube. "Relax on things you think you know and open to success."

[@mr1rapid]

TerraceThornhill I would like to add that all of the hi horse sport bikes are running chains because simply put chain is the purest means to transfer power. The power loss thru a chain is less than anything else. Think about those guys doing 80 -90 mph wheelies down the interstate on bikes that can go 200 mph. They are all running chain.

[@garybucher6824]

@@mr1rapid i was gonna say I've had bikes with chains up to 185 no problems.

[@TrustJesus100]

Looks great! I'm about to modify a Subaru 28hp fuel injected. Gotta design and build a reduction drive, so my question is how do you know what size pulleys you need? I'm gonna go with a cog belt style.

[@flyingham2640]

I was wondering how you dealt with the thrust loads. Trying to figure out how to integrate a thrust bearing into the prsu. thanks.

[@calynnbrady9997]

You sound like actor Nick Offerman from the show parks and Recreation the guy who played Ron Swanson! LoL

[@roderickbanks8596]

How about a no PSRU ECH 38HP Kohler Command EFI installed in a Legal Eagle. I found one way cheap on eBay. Install an aluminum flywheel for weight savings but still swing the prop direct drive?

[@stanleydenning]

I wonder if making the exhaust headers a little longer would help in scavenging. Therefor increasing H.P. a little. Maybe tow into one and use a motorcycle muffler. What do you think ?

[@RonBesse]

So sorry for the super late response to your rather important question. I believe you already know the answer, so I think this is more for others reading through the comments. The simple answer is yes. I had built an Experimental biplane using a 2332 cc type 1 VW conversation (150 hp @ 4800 rpm) ,and a Folker E III ultralight, that I designed and built using this exact Kohler engine. Both planes I had taken the exhaust pipes and had cut angles to the relative wind, so that it formed a slight vacuum to the exhaust pipe as the air passed the end of the pipe. This in turn (theoretical) would scavenge any spend gases left in the expansion chamber when the piston was at top dead center of the exhaust stroke. To figure out the proper angle for each exhaust pipe, I had to figure 90 degrees (for each pipe) realitive to the wind. Then I took a plastic medical syringe, removed the plunger, and attached a vacuum gauge to the other end where the needle twist in. I held an air gun blowing 90 degrees to the flow of air and would cut slight angles from the plastic tube until it reached a maximum vacuum on the gauge. Then I would cut each exhaust tube to that angle realitive to it's wind flow. This amount of effort is really only needed in a competition type application where getting every bit of energy out of an engine is paramount. In the second video, I had changed to just a stock Kohler exhaust just to drop the noise levels, but far from a proper tuned exhaust system. For this single seat trike, it had way more power than what was needed. It's cruise speed was only 39-40 mph. In the second video, from start to that white mailbox to my right, I was doing 42 mph. You hear me let off the gas, because after 45 mph things get real stupid steering with your feet with that short of wheel base. Lift off was at 35 mph anyway. I've sold this build and have been flying PPG lately. I'll be posting PPG videos soon. Soooo much fun and convenient to load up and go. Storage space is like nothing. Thanks so much for such an intelligent question, Most Sincerely, Ron.😎

[@plasmaguy5]

very cool

[@chwilliams5]

It looks like there is some chain slap going on there.

[@hadleymanmusic]

Dad had the kohler commander with direct drive

[@alltheboost5363]

I'm going to be building a very similar setup but using a 212 Predator engine they're only a hundred bucks I'll end up spending way more on Parts... but I'm thinking about using a torque converter instead of a belt reduction or gear reduction.

[@petroelb]

I'm guessing that your Predator 212 didn't have nearly enough power to get you in the air? Or did you use multiple?

[@kelvinramdall1434]

I'll be the drag on this project with a few silly questions. What is this particular frame made of, I gather it is aluminum. With motor and all what is the weight? Is the front wheel steerable? What made you decide to use the 4 blade vs any other? Thanks for taking time to reading and replying.

[@RonBesse]

The Frame is 2" x 2" x 1/8" 6061-T6 Aluminum and all the supporting and mounting plate is 1/8" 6061-T6. All hardware is A&N bolts. All up weight including the wing is 240 lbs. Front wheel is steerable ( framework is aircraft steel), and I used a steering dampener from a Suzuki street bike to stabilize it for speeds over 40 mph on the ground. Propeller selection can be discussed in volumes, but I'll try to make this as simple as possible. I had this engine in a Fokker E III, that I designed, built, and flown before this flex wing trike. I ran a 72" ground adjustable Powerfin 2 blade propeller on it. I also tried a 3 blade 72" ground adjustable Warpdrive propeller just for fun. Determining the pitch is irrelevant, because these are not certified propellers, so the dynamics change just going to a different propeller type or profile even within the same manufacture. Example: Powerfin "B" blade profile vs "F" blade. Some propeller makers go with a thick and wide base area and thin and twist as they increase in "r". Some don't. Talking to the propeller manufacturers, you find out really quick that unless you are just bolting this propeller to a well known application they are stumped. Most are Mom and Pop owned businesses, and don't have the background to understand flow dynamics, etc... They play around until they get something that works and then market it in a very limited high competition arena. Not that this is a bad thing, it just is. Doing the math a head of time, I knew I was going to be in the 40 hp range with 2.5 :1 reduction, rpm, engine displacement, etc... This narrowed the selection, because I was looking for a propeller like that used on a Rotax 447. On the trike, I had a limiting issue of ground clearance that I did not have to worry about in the Fokker E III. I could have went with a more efficient three blade propeller of say a Powerfin, but those are stupid expensive. If I went with a 60" three blade Ultraprop, then I would have to install much greater "degree" blocks ( bigger bite) to bring down the top rpm of the engine. Because the trike cruise speed is 40 mph, I needed a pitch in the propeller to match for best efficiency. Therefor you end up with the 4 blade 60" Ultraprop. Fewer blades are much more efficient, but like WWII airplanes high hp low ground clearance gives more blades. Hope this helped, and no you did not ask any silly questions, Most Sincerely, Ron.

[@KevinArmstrong4154]

Gosh! Mine had to have rubber mounts to tame the vibrations, with a multi-V belt drive, what wing and speed are you at please? Kev

[@bensefton3413]

How are you managing the thrust on the prop shaft? I see the housing with the 2 mounted bearings to contain the axial movement from the prop, and also the threaded end of the shaft against the taperlock, but didn't see any thrust bearings. Also, would you mind sharing your source for the bearing housing, and which type of bearings you are using?

[@vg23air]

94 lb engine minus 22 flywheel plus 11 alum flywheel plus 14 redrive is 97 lbs estimate 84 lbs, what was the other 13 lbs taken off ?

[@jimmyboy163]

great in-depth video....I do see some chain slap during your run up around 26:30...is that an issue?

[@quachtinhho]

Good like!!!!.

[@gospeedracer40]

Hey great video, any up dates on the engine? how many hours do have on it now?

[@dynomania]

Runs great how many HP would you estimate?

[@lapper1111]

Hello Ron how would I get information on converting a Kohler engine just like the one you’re showing. I am building a air bike aircraft. And I think that engine would work out for me.

[@ikay2102]

Simple. Cheap. Forever.

[@saadsaifaddin3258]

Dear Sir hope you doing well i have a question 1. can i use normal motor cycle engine ? 2. how can i know what tip of engine is ok

[@SigurdtheRyder]

I am wondering, and you commented on aftermarket parts...did you leave the stock rods in or replace them? Most engines of this tyoe are governed for 3,600 rpm..so what internal changes were necessary to get the 5,000 rpm you run now? Enjoyed and learned a bit from your vid thanks for sharing it! Robin

[@RonBesse]

Robin Snodgrass Hi Robin, First I had to take off the stock carb, flywheel, Smart spark ignition system. I went with a Mikuni 38 mm carb, then a Midwest Super Cub Aluminum flywheel set to 31 degrees before TDC, and older style magnetos. In side I removed the governing gear and control rod (just to get it out of the way).I went with an aftermarket solid custom cut cam and push rods, but this was a waste of money, because I'm not throwing enough rpm to need it. Could have saved $500. Before settling on the 2.5:1 gear ratio, I though I may be running up to 6500 rpm. I only can run up to 5000 rpm with the 14 degree propeller blocks and 60" diameter (or Tan@ x 2 x r x 75 % x 3.14 = roughly 38 pitch) for my 4 blade Ultra Prop. The connecting rods, pistons, heads with valves and springs are all stock. Again not throwing enough rpm or 8000 rpm hole shots ( motorcycle drag racing) to need it. We are only compressing air with about 45 ft-lbs of torque at 2600-2800 rpm ( less than 6 gallons of water held 1 foot out). This engine is used stock in commercial tree stump grinders. That's like one never ending propeller strike to us LOL. I hope this helps and thanks for asking. Ron Besse

[@johnkcrabtree]

Where did you get your components for putting the chain and propeller stuff? I want to build one. But for the life of me don't know where to find this stuff

[@claytonbuckley8626]

That’s an awesome looking flywheel, where did you get it made??

[@jimmyboy163]

also, I don't see motor mounts. I'd do something just for the vibration....

[@CoolAirVw]

14.7 to 1 is ideal for a catalytic converter. Its not ideal for fuel efficiency or for power.

[@sciencemilitia1853]

14.7:1 (approximately) is the ratio for stoichiometric burn. Exact amount of oxygen the burn a given amount of fuel. No more, no less. But you're right. 14.7 won't give optimal fuel efficiency, or optimal power. Gotta richen it upcfor more power. Approximately 12.5:1 is good for peak power. Optimal ratio for peak fuel efficiency varies from engine to engine.

[@charleytownsend5725]

Hey i am a Kohler tech with those rpms u have a chance for valve float u have.hydalic lifters in that motor u are chancing it after 4400 rpms

[@RonBesse]

I ran this engine for seven years before making this video. Hundreds of hours. I actually don't know the exact hours, because the hour meter had been reset a few times by my kids pressing the reset button. I tried a solid lifter cam and solid lifters from Midwest Super Cub, but because it was cut so close to stock lift and duration, I could not see a significant increase in performance. The $500 would have been better spent on the stroker kit they sell. Would have gotten better torque and hp at a lower rpm. By the second video, I had the original hydraulic lifters and cam back in. I also changed to 14 degree blocks on the Ultraprop from 13 degree. This dropped top static rpm to 5000. Also added an idler and changed exhaust. After the second video, I went back and tried the stock carburetor just for fun. Turned out I got a much better idle and very linear throttle response through out the full rpm range. I also gained 120 more rpm's static. Ended with 5120 top static rpm's on a 90 degree high humidity summer day. This trike had way more power than I needed when flying. Never an issue, ever. Can't say the same for the 2 cycle paramotors I fly with now.🤔 The pull tractor guys running in the stock class are not allowed to change a whole lot on the engine (I've been told, but I reserve the right to be wrong.) I've read that one guy was doing 7500 rpm hole shots with stock engine. Not sure how long it lasted, but impressive if it lasted just once.🤓 Check out their website and KZbins cool ass shit I think. Back to your statement about the hydraulic lifters, I'm sure at the higher rpm's, especially on aged systems, there will be some sloppiness, but unless it's noted in performance or bad enough for a piston to slap a valve (that's really bad) , then it's inexpensive to replace stock parts regularly on these engines compared to Vittorazi Moster 185, or Air Conception Nitro 200, or Polini Thor 200, etc... Paramotor engines. Rotax stopped making the 447 and 503. That was the whole point of this build. No where near the best way to do this. Just simple and cost-effective, and it worked flawlessly for years. Thanks for the information and comment, Most Sincerely, Ron.

[@Survive2022]

With your knowledge, would this be a good powerplant for, 103 ultralight? Using a reduction drive like yours on a single cylinder, four stroke to get the 40hp? There are single cylinder, diesel engines that are around 52# that have a hp rating of 11 @3600 rpm

[@RonBesse]

Yes, very much so. This flex wing trike is a 103 legal ultralight (254 lbs or less). I had this engine in a Folker EIII ultralight, that I designed and built before the trike. I did go back to using the original kohler carburetor. It worked out to have a much better idle and could still reach the 5000 rpm's with no heating issues. Just so you know, I had been using this same set up for 7 years before I made these videos. Just did the mods between the two videos and changed carburetor back after the second video. The flywheel came from Midwest Super Cub. They also make a stroker kit for these engines that's worth looking into. I have sense sold the trike and have been flying PPG. Thanks for commenting, Ron.😎

[@raydreamer7566]

How many hours do you plan to use each chain ? Chain is cheep. I was looking at a used Hummel bird and was thinking of one of these motors for it. Newer motor , electric start , and easy replacement of motor and parts. Again great video.

[@RonBesse]

Hi Ray, I love the Hummel Bird design, I even have a new set of plans for one around here somewhere. I have been watching the chain really close to see signs of ware but as of now nothing. There is the expected oxide coating gone from the rollers that contact the teeth of the sprockets. Remember that the 725cc engine is only producing a little over 40 ft-lb of torque at 2800 rpms, or the weight of about 5 gallons of water held one foot out, LOL The chain is rated at 5000 lbs. I know massive over kill. Its about twice the size as most motorcycle chains. This was the chain I had planned on using for the 2332 cc type one VW engine in my Biplane (150 hp @ 4800 rpm) It produced over 500 lbs of static trust. This engine is producing a little over 200 lbs with the 13 degree propeller blocks and a little less with the 14 degree ones. I have put on a 15 tooth idler gear on the return side and an oil filter side mounted Kohler exhaust since this video. Much cleaner setup than in the video. Should finned off some of the KZbin Trolls now haha. E-mail me Ray if you have some questions, so that I can send you pictures etc... Ron Besse.

[@JoseRamos-su3ep]

Rob!! Are you still out there??

[@konstantinoskatomeris3851]

thank you for the information! if you put direct drive propeller what diameter you nead? happy flying

[@RonBesse]

+Konstantinos Katomeris Hi, I would not recommend using direct drive propellor hubs on these engines for a number of reasons. These engines are only designed to handle rotational forces and do not have a thrust bearing to handle the push or pull forces produced by the propeller thrust. Also, the full weight and vibration of the propeller is placed directly onto the crank shaft and then transferred through out the rest of the engine. Lastly, the thrust produced by the engine would be so low, that you would be greatly disappointed in the performance. You would need a very short wooden propeller and keep the outer rotational speed under the speed of sound. All this being said, people have done this, and it can work. Some of the Kohlers and others do have models with thrust bearings in one end of the shaft, but you would need to research that more from the manufacturers. Here is a link that I often use to simplify calculations. personal.osi.hu/fuzesisz/strc_eng/ Thanks for watching the video, summers coming, and I can't wait to get out and tinker some more. Ron.

[@konstantinoskatomeris3851]

thank you so much.your knolege helps. do you have any experience-opinion with the clone engined lazair?

[@randywinner111]

+Blankbiplane I'm confused. @3:21 to 3:57 in video I thought I saw where this engine has no thrust load at all,, as the "Thrust Loaded" portion of this adapter plate looks to be mounted to case. The props horizontal thrust line is more in line with the upper end of motor to me? The fact that the prop hub is not connected to the crank at all leaves me to ask where is the Horizontal thrust load on the crankshaft? Or did you mean something else? Like I said I'm confused?

[@joelperezgumba]

Quick question, what mm bore mikuni carb is that? I have various sizes around, just wondering if I happen to have one already. Thanks in advance!

[@RonBesse]

Hi Joel, I had a 38 mm carb on it in this video. After the second video, I went back and put the original Kohler carb on it just to see if I could get the same rpm's at top end. I found, that I actually gained 152 rpm's more and it was a much better idle. Temperatures were well within kohler specs with very smooth power throughout the rpm range. With 14 degree propeller blocks it topped out at 5152 rpm static. If you watch the second video, where I'm messing around in the neighborhood. The last start and full throttle scene, I'm doing 42 mph by the time I passed that white mailbox on my right. I only needed 35 mph to take off and cruise was 39-40 mph with the wing I had. Way more power than needed really. I had sold the trike shortly after the second video. I've been flying PPG ever since. Ran that engine in two different aircraft (over 7 years) with absolutely no issues. You may want to check out Midwest Super Cub for parts and ideas. They build kohler performance engines and racing parts. Most Sincerely, Ron.😎

[@MrShaneSunshine]

Hello! I would like to build one of these - what do you figure your total cost was and do you have a bill of materials or a parts list to work from?

[@baronvonkaiser9912]

could use this for the raid tomarrow

[@65LB]

Wanta see it with a wing and flying

[@tmoney1572]

i was wondering why not use a sport bike engine for a small aircraft or ultralight. lighter, way more HP... good on gas.

[@2secondtony748]

This entirely possible, the conversion would mostly consist of gear reduction and working around the factory gear box

[@landonpearson93]

Please put a chain tensioner on it I see that thing walking around like jump. The reason you would use a belt, when it breaks it doesn’t go through the prop Safety wire your air filter and your exhaust so you can keep a prop.

[@laidbackzach29]

Where did u get sprocket on engine

[@ashleyalexander3463]

Could you sale me what I need for the drive

[@hadleymanmusic]

I had that CL model!

[@hadleymanmusic]

It flew quickout of dives

[@kleberaviador5423]

hello cmte, does this kohler engine heat up in flight without the original fan?

[@RonBesse]

No, it's with any air-cooled engine. If the air to fuel ratio is correct, you can hold it as high or low rpm as you like with no external fan or propeller, and the engine will not get hotter than your target temperature. I used a 2332cc high-performance vw type 1 air-cooled engine in my black biplane. I would remove the propeller to run tests of different types. It produced 150 hp at 4800 rpm with a Holley 350 circle track two barrel carburetor on it. 6" blue flames were coming out of the short exhaust pipes. The next fuel charge is what cools the engine. Water cooled engines just get the advantages of running a bit leaner for better fuel economy and slightly higher performance and slower temperature changes to an engine in extreme weather conditions.

[@kleberaviador5423]

thank you for the explanation

[@frederickbecinaencio8161]

can you make your own wing ?

[@charlesoben811]

Thanks. this is a good one. I will like you to teach me how to build one. how is it possible? am in AFRICA

[@mrbradgeary]

is it solid mounted?

[@dwightpruitt6809]

5500 rpm ?

[@albertmoore1479]

Why reduction?

[@philroe2363]

Several reasons: 1) much larger prop diameter = better efficiency due to reduced speeds, 2) Larger, slower prop produces greater low speed thrust for climb, 3) and probably most important - it has a tendency to isolate the prop loads from the flywheel, reducing the chance of a stress reversal on the crank, which can cause catastrophic failure. You can see the slack chain on the side downstream of the prop pull by the engine . . . that dancing action of the chain, if it were not doing that, would allow the prop inertia to impose load reversals on the crank (i.e. opposite the direction the engine is spinning the prop). Take my word for it . . . that is a "no-no" from an engineering standpoint.

[@hadleymanmusic]

You recarbed?

[@2950johndeere]

Cam you pm me id like to know where to get the prop and a few other details so I could set one up on a boat

[@RonBesse]

scott offerle Hi Scott, glad to help with your boat project, If you e-mail me at [e-mail], I can send pictures etc... and I get alerts on my phone, so that I can respond back faster. Ron Besse.

[@hadleymanmusic]

Whos got the aftermarket flywheel?

[@patrickroher4760]

Greatfawknvid sir. I remember Kohler when I was a kid, I'm almost 60 now. Any thoughts on the EFI engine? BTW This is my alias, a certain tube dosen't like my politics. One-to-many rebuttals to.cnn I think. Lol.

[@RonBesse]

EFI would always be better than a carburetor as long as they don't have a rpm limiter keeping the rpm's from reaching your target rpm.

[@bruceruttan60]

Please publish drawings!

[@feriirawan6472]

buddy, i want to ask, how many horsepower your engine

[@RonBesse]

Hi Feri irawan, It produces 41 hp at 5500 rpm with a 2.5:1 gear reduction. That is with the 13 degree propeller blocks in the Ultraprop. I use the 14 degree blocks now, so maximum static is 5000 rpm now and getting about 37.5 hp max. The idea was to find a 4-cycle replacement for the discontinued 2-cycle Rotax 447 engine. I have added a 15 tooth idler gear on the return side of the chain and a factory oil filter side mounted exhaust since the video was made. The idler took out the free play, but made no differences in performance. The exhaust is much less noisy like a ridding lawn mower now and looks cool too. Thanks for watching, Ron.

[@feriirawan6472]

oh yes, thank you very much,. what if in full gas,. how many horsepower / (hp)

[@65LB]

HP?