Hi Love your post. I have the same engine and looking to do exactly this conversion. Where do I get the timing rings and what is the timing on the motor. Kind regards Bobby

This is the first RC engine I ever bought. I didn’t even know what it was. It took years before I was impressed about it what I had.

Hello sir. Love your videos. I have a engine that i got and im not all to good with trial and error to get it to run. Do you have a po box that i can send to you and you configure. Thanks

A l'epoque. J'en ai eu deux ....de tres beaux moteur. Des usinage magnifique mais tres fragile et pas fiable....de plus ils étaient tres onéreux...!! Belle video merci

Thanks for this!

I’ve got a 2000 and 3000 in boxes I bought off of eBay dirt cheap. I better get em out and fire one up. I also have a Balsa USA Stingray 120 I thought about putting on after it’s built.

Awesome

That's quite a coincidence; my Enya 80 was also my first rc engine as an adult. I still have it. Runs beautifully. Had it in SIG Citabria years ago.

Excuse me, I'm relatively new to the hobby and I'd like to know how to get started? For example all the equipment I'll need and how to set everything up pre and post run? Thanks!

Brilliant demonstration video. That has really helped me understand how to carry out this procedure. Many thanks.

Very clearing story SIR,i'm 2 stroke mechanic,your hands show your experince, i never trust internet story's from People with clean hands or smooth you tube BABY face, Internet geeks ruïn the hobby,thanks you for your video ,totally correct, wd 40 for cleaning ,perfect,moist removal,perfect,love your treu facts,total correct!

ОГРОМНОЕ ВАМ ЧЕЛОВЕЧЕСКОЕ СПАСИБО, УВАЖАЕМЫЙ ДЭВИД !

Dave, I must say, I'm quite impressed with how the TT FS91 seem to perform in this video. I just picked one up, NIB off of eBay. $169- and these days (2024) that's a pretty good price. I want to put it in my brand new Great Planes Revolver. After reading the comments here, I think it wise to replace the original plug with the OS type F- the one you mention in this video- to ensure I get the RPMs, both high speed and idle, that you achieve in this video. I'm just wondering how long of a break-in will I need to be able to trust it, sideways mounted, in the Revolver. Also, I was wondering your thoughts on mounting it inverted. I do have a FS90 Enya mounted upside down in a Goldberg Chipmunk and it runs quite dependably. The Revolver seems to have adequate ventilation in the lower portion of the cowl, eliminating the need to cut a hole in the side, making it more aerodynamic and aesthetically pleasing. Thank you for all your efforts in providing us with these fascinating engine reviews. This one was quite useful to me.

I was kinda worried that without the cover the belt would slip off the cam pulley. Or is it valve pulley for this engine? :D

Great video! Congratulations

Très beau moteur et un beau bruit

Thank you very much for recording the video.

Is denatured alcohol as hydrophyllic as methanol?

Howdy David, I always enjoy seeing different and unique engines. Thanks

Try nos fox miracle 4 stroke plug. I bought a bunch years ago. Nothing today seems to work as good although the O.S. F plug seems to work well for me.

Runs really good on #8 plug to be a 4 stroke, the best performance in a 4 stroke with a #8 plug i ever seen!

Are there any NOS timing belts around for these engines?

Hi David. Glad to see, you didn’t give up. And congrats for this cool run.👏 Also thanks for the image of the valve timing. I’m absolutely with you. It looks pretty perfect. And as I also mentioned about the OS F plug, I was happy to see this engine running so fine with it. That’s quite the same as I experienced with my Webra T4-40 engine in the past. 👍

It's just murphy's law! - as soon as you try and show something to someone...

Brilliant video and well explained.

My SF61 all of a sudden wouldn’t start. Usually it’s super easy to start and very stable. Found out that the plug screw was gone. Must have vibrated loose or something. It’s nr 8 on the explosion view. I don’t understand what it’s for. Anyone who knows?🤗

Hey David, apart from the fantastically running laser 80 in this vid and the equally lovely Noah cat, I've a question: for long-term storage, after ending a session, do I save the bearings inside an engine by "drowning" it in FAI fuel? I mean, will it protect against the effects of any tiny residue left from the 12% Nitro fuel I'm using (I always "dry out" my engines after each session)? Or am I just wasting my time, thank you in advance, Regards Harry

Hi David. I came across your channel quite by accident and wish i had found it years ago. Some of your engine videos take me back to the 50s 60s in England when i was a lad just getting into model making. my first model was a Cox plastic control line plane with a cox Pee Wee motor. then i graduated to making my own Balsa and tissue paper models powered by small diesel engines, we would make our own fuel ( castor oil, ether and paraffin <kerosene>) but i digress. I have been looking for about 5 years for a long ago discontinued OS four stroke engine which was for model cars. OS FS 40S-CX and after finding your channel i thought this guy may have one, know someone who has one or can point me in the right direction to find one. I would have liked to have emailed you direct but the 'About" section in your profile no longer exists so there was no way to find your email address. Accept my apologies if i have been waffling on but my hopes have been raised just by finding your channel.

No matter what oil is in the fuel, the OS engines with piston ring always run well.

Great video David. Good comparison of prop performance. I think the transition issue is the plug. It’s a two stroke plug and webra make hotter plugs than the 4. I’d run it with the IS F it’s way more suited especially with low nitro fuels. Other thing you could do is run high nitro fuel like 20% on this plug.

I enjoyed watching this engine run as well. I think I agree with you David, I need to look at previous videos but I remember the engine running a little bit smoother with the #F glow plug. Especially noticed the difference at low rpm.

Great videos###

Hey, Dave! Can you tell me in which order does the crankshaft spacer/washer go in the assembly? I was given one of these (R/C version) from another club member. However, it was in pieces and missing some pieces. One of the missing pieces crankshaft washer. Obviously, the crankshaft has quite of bit of end play with out this washer installed. I saw a cranshaft washer shown in one of the pictures on the Sceptre Flight review for this motor and I'm trying to make a substitution using a prop washer I had laying around. However, I can't seem to find an exploded view of this engine anywhere on the web to show where it should be installed. The tapered cone design and lack of bearings of this engine is also new to me. Most of my engines seem to use woodruff keys instead of the tapered cone design. Just can't seem to figure out how it goes together: hoping you might be able to shed some light on this for me. Thanks!

Happy to see this beautiful engine back! Shes tricky! Sometimes, likes load, and not that much RPM, sometimes less load with more RPM. Anyways... a beautiful engine, that I ll be glad to have just to appreciate and of course run it. Thank you David

It's good to see this webra engine test with 4 different props, i think maybe the webra#4 is not performing as well as we saw on the other videos with the os f glow plug, at least at this stage in the break in process. As always your vids fulfill my need to hear glow engines running. Thank You!

Glad to see the Webra 40 back with a 4-prop test, as one guy below suggested I'd stick to what works best with regard to glow plugs, that being the OS F generally. I'm somehow convinced it should both idle and transition much better with that plug. Nice run though, thank you.

Hi David. I still think there is a little timing error in the valve timing. If you disassemble the belt cover try to find a little point on the upper belt gear. I thought seeing a little point slightly on the left side top (about 11 o’clock) directly under the teeth of the gear on your disassembly video. Can you confirm that? Because this point should be absolutely on top as I remember my engine I had. I always ran my engine on OS „f“ plug and it ran very fine. Much better than the original plugs of webra.

Hope to see it run again, maybe with an 11x6 and a few different glow plugs. I'm glad you are enjoying Wisconsin!

Hello David, big fan here, I recently bought a brand new bully 1.20 LS from an old timer, there are no videos on tuning the carb and internal pump and very few info in forums, is it possible to feature that engine on your channel somehow ?

Nice I picked one up about a month ago in a package deal 100 bucks for the engine and plane kit and all to complete it I've been running os in my planes for years and have always been pleased with them great to see that you're still enjoying running rc engines as a hobby keep the videos coming 👍

Another well manufactured engine. It should be another great acquisition of yours.

very good run. ,its an OS. i prefer the ring engines. i still have a new,61,fsr,ringed motor,never started. maybe, one of these days.

Got one myself, also new in box. Will keep that way for a while. Nice video as always, enjoy watching 🙂

Nice run. I suspect a single flip would get it started, but I know you have issues after so many years of hand starting. Great engine. I’m breaking in a K&B 65 Sportster. After around 30-40 minutes it is only getting close to your OS initial run. The SF are the the best series.

OS never dissapoint specially the SF series, in my opinion the golden era of 2 stroke OS engines.

Nice steady first run! funny I have just come in from running a OS 25 SF flick started and ran spot on! OS!! say no more, the SF range have always been top of my list, I have three 25s WHY? can't stop running the things from the age of 10 now 65!!!

Thanks David! Sounds really good.

In some engines plug so hard closed properly!

Ah, yessss...The moment of satisfaction when an old used or new-2-U glow engine fires up easy for the first time, or the cheap thrill when it breaks into full tenor and you feel the resonance through the needle valve. Its all still there every time I make a run like this. 'never thought I could love a Thunder Tigers or tune a Super Tigre, but thanks to your show, all are now tamed dragons and pet cats in my Ready Engine Cabinet. Castor oil is not as strong as rat poison, but it is still addictive. Thanks, for the videos.

Being that the carb and exhaust is opposite between these engines, I'm thinking that one runs clockwise and the other counterclockwise. Just my guess.