How-To: Carburetor Idle & Pilot Screw Adjustment Honda XR70

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[@fucheduck]

I learned long ago that these smaller engines are not supposed to sound like a car. the idle is not supposed to be as fast as a Dodge 1500.-or a Ford F150(at the time I owned my cycle). the tiny engines (I had an old 110(105 cc) should be barely running. should not sound like a pickup truck! that engine looks just like my old 1985 110 ATC. That one used lots of gas because it idled like a pickup truck! I messed with it, Dad messed with it and then told me it was too rich. Also even if you don't want it to stumble you don't want it to sound like a pick up truck after a long day's work, or an electric company generator.

[@nadakidd]

Never opened a carb before tonight. Watched your video and tuned it (after cleaning it) and it went exactly the way it did in your video. My crf100f runs perfectly now. For the first time it starts with no choke on a cold engine with no throttle input. And I can set the idle wherever I want. Thanks Matt!

[@LoneWolfSnowplowing]

If it starts cold with no choke you’re rich. Cold engines need richer mixtures.

[@dennism644]

I've watched many videos of how to clean adjust rebuild and upgrade a motor cycle carb and I like all your vids you rock....and the whole town of Uhrichsville ohio likes ya to .I own Dennis Carb here ...I really dont get into motor cycle carbs or small engine I do however get into almost everything else.from vintage autos to domestic some foreign....so I thank you very much for your type of how to vids. Knowledge is powerful stuff.......thanks DennisCarb

[@dennism644]

@Saint Malachi so you dont trust your girlfriend then wtf you doing with her and why leave your petty bs here no one gives a shit.find someone to obey you and get on with your life like your a freaking angel.got a motorcycle then why do you need a girlfriend dumbass.

[@segurajuan13]

Can you help me? I have a 2007 crf70 and I’ve got it to idle at 1.5 turns out on the air fuel mixture screw but when I give it full throttle or put the choke it bogs out any suggestions

[@monksapollo735]

probs dirty or clogged carb, try cleaning it out.

[@buddyboy8056]

@@monksapollo735 i also had that problem and i cleaned everything on the carb and still have that prob help please

[@monksapollo735]

@@buddyboy8056 and you've double checked your pilot and main are not clogged?

[@buddyboy8056]

Monks Apollo yeah checked them and see clearly threw them, I changed the depth of the throttle needle down a notch and changed the jet a couple sizes smaller and she rips now!

[@buddyboy8056]

Thanks for your help with everything tho!

[@madscotsman3390]

After rebuilding a CRF70F carburetor, what is the factory start position for the throttle stop screw? Will this screw preventvyhe bike from starting?

[@ez7541]

Thank you Matt, Very much appreciate you taking the time to go over the adjustments in such a layman friendly way (and without wasting 10 minutes talking about totally unrelated stuff). Keep em' coming good Sir. -Ez

[@HTMR]

+Ezzy k Haha...no problem. Glad the vid helped.

[@abemichau4706]

OMG THANK YOU. turn the air screw in = rich out = lean, 27 blogs and 14 videos, I finally find what I need to know THANK YOU Mat!!

[@HTMR]

+Abe Michau Awesome! Glad it helped.

[@abemichau4706]

+MatthewMCRepair heck ya bud! had a no start issue on my kids xr100. pulled the plug and saw nothin but black soot. "to rich" unfortunate that Google sent me on a wild goose chance b4 finding your cannel. great stuff here, Im learning some good tricks and tips.

[@podgebrennan1]

I don't usually comment on videos but this was a great lesson from a great teacher appreciate the vid

[@jeremyvillalobos9752]

Perfect explanation, thank you! After one video I've subscribed! Using this info on my 65 CM91, hard to believe even with all the honda books it wasn't said better than this. Thanks!

[@luke-bv3vr]

hey i have a very similar carb and i put it on my xr70 2000 but my bike won’t start. i put everything on right. any problems that you could help with because i can’t figure out why it won’t start

[@HTMR]

Is the plug getting wet? Give it a shot of starting fluid.

[@DurbinsBourbon]

Thanks for the video. My little 2002 XR 70 would not idle by itself after I cleaned the carb out. After watching I had to dunk around with it but it runs great now! I’m no mechanic by any means. You helped me bring that bike back to life again from my sons to now my grandsons. Cheers 🍺

[@austinkendrick1722]

Ok

[@DavidGonzalez-sx3db]

I’m having the same issue my sons xr70r only runs with choke on,cleaned carb still not idling alone ,gonna try this

[@alex86ajb05]

I wanted to ask about these adjustments. At the beginning of the video you say to get the bike warm to operating temp. What if you cant get it to idle or run to warm it up?

[@ard5608]

Use a propane torch to warm up the engine and carbs. Works like a charm. Yes im kidding.. If you can't get it to idle, you've got the wrong jet.

[@Sms8668]

ard5608 Wrong Jet ? Hilarious

[@online12plus]

i tried using a whole lot of starter fluid. $3 a can

[@carguy03]

I have a trx 90 and when u start it up it's wide open and I have turned that screw all the way in with gonna fall then took it all the way out and still running the site

[@kylegoes8119]

Or just tirn in both screws and turn them back out 1.1/2

[@erickirksey3342]

Need help, idles great, but doesn't like wanna whined out, sometimes it won't even move forward? Please help 1995 z50r Thank you , carb adjustment video excellent

[@camronbrewer5760]

Matt, Thank you. What would you say is the problem if the air fuel mixture doesn't seem to do much at all when you adjust it in or out and also if when you give the bike gas the idle seems to linger high before it drops back down? Did you ever make the video you said you were going to do on adjusting the needle, and the main jet etc? Thank you in advance. Love your videos!

[@HTMR]

What year make model? First check for vacuum leaks. If it does not make any difference, then something is wrong or the pilot jet is the wrong size. The hanging idle you have means it is lean. Again, check for vacuum leaks: kzbin.info/www/bejne/pXy5eaR5f7Nlgrc Main jet: kzbin.info/www/bejne/bJOclYCenL-HY8U

[@camronbrewer5760]

MatthewMCRepair you rock. It's a 2004 CRF50....

[@HTMR]

Check for vacuum leaks, make sure carb is clean. Any mods to the bike?

[@camronbrewer5760]

MatthewMCRepair no mods. Stock airbox... I'll check with saran wrap...

[@HTMR]

Saran wrap???

[@The77stevo77]

Dude. Very nice video. So straight to the point. You explained everything simply. Video shows everything. No cheesy music. Thank you. You rock

[@HTMR]

Thanks!

[@sliverchicken1799]

Dose anyone know what size bolts you need to mount the carburetor I lost mine

[@Educatefully]

my engine stops when I am closing the screw. However, there's no difference when I'm widely opening it.

[@shanejones5885]

Not bad, but most people don't know where to start their idle. You're suggesting they run it for 10 minutes, which would indicate their idle is decent enough to run for 10 minutes. Consider starting from base or bad idle.

[@MrIngorodrigues]

If dont idle, you "must" to screw The "idle screw" that directly rises The main needle.

[@Maxumized]

The pz22 looks just like your carb but I think the screw meters fuel if I’m not mistaken?

[@GreatBirdOfHope]

Won't stay running without choke. With choke idles and revs well. What screw should I adjust so it won't die when I let off the choke?

[@beastpump957]

Brother can you make a video on how to replace air filter for XR70 because i want to do the job for may XR150

[@julietquebec7553]

Hello, i'm your new subscriber from KSA. I'm actually from Philippines and having a Honda TMX 155 but currently working here in KSA. I enjoyed watching your videos and a learned much ideas about carburetors. Next time I will play with my carburetor back in my place. More power to you.

[@user-ck7si1os9u]

My 70 starts and runs great. When iturn the choke ON it dies. Any idea why it would die when i turn choke on

[@KillerofChaos7]

Hey, so I have this issue with my 2-stroke where, after coming off from full throttle (going quite hard on the gas) and going to idle, the motor will stay running strong but gradually start dying to a point where it runs at the lowest rpms possible for several seconds before cutting off. If I blip the throttle, which I have to constantly keep doing when this happens, then it'll keep it alive for a few seconds before going right back to the extremely low rpm range again. This ONLY seems to happen after having went hard at full throttle; it'll idle perfectly fine otherwise if I've been riding between 1/4 and 3/4 throttle. When the engine does die as a result of this, I just let it rest for a bit before starting it up, and it'll stay idling right again until I eventually go full throttle and idle from that again. I'm aware that ambient temperature can play a role in this, too, and all, but I've seen this problem occur during both cool and warm days. Checked for air leaks and found none whatsoever, btw. At this point, I'm not sure of what to do here. Carburetor is an OKO 21mm; pilot jet is a #55 with the air screw around 2 turns out from fully seated.

[@uchetia]

Did u fix it? I have the same problem

[@mikenobbe1135]

it runs fine through threw gears at mid throttle any more bogs

[@HTMR]

Try lowering the needle clip position. Does it run better if you partially turn choke on?

[@mikenobbe1135]

MatthewMCRepair runs good choke half on

[@mikenobbe1135]

MatthewMCRepair did not try needle yet

[@HTMR]

OK, it wants more fuel. Lower clip position and play around with larger main jets.

[@mikenobbe1135]

MatthewMCRepair thanks will let you know

[@jakkelly2037]

My crf70f only runs on choke and I and it will hardly run at high rpm

[@HTMR]

Clean the carb.

[@jakkelly2037]

@@HTMR I have pulled the whole thing apart and everything is very clean

[@HTMR]

@@jakkelly2037 New problem or has it always done this? Anything change modification wise?

[@jakkelly2037]

No

[@HTMR]

@@jakkelly2037 Check for vacuum leaks. www.howtomotorcyclerepair.com/how-to-diagnose-motorcycle-vaccum-leaks/

[@michaelcline328]

I ordered carburetor for ttr50 Yamaha throttle on my on the side this one don't have it just a sprout on top

[@catalinacatalina1474]

Hi, for 80 cc malossi with malossi exaust and 21 carburator what idle should it be? Now I have 50 idle wich I thinks to big... main is 98.. thank you

[@matthewh9407]

Hi there. I'd assume on a dirt bike, you're not too concerned with fuel economy, but for a commuter (mostly street) bike (in this case a DR650), would the approach be the same? I've always thought that the engine should sound right in the verge of stumbling at idle. Like 90% smooth, but a little bit farty here and there to get good efficiency vs power. This is all just using my ears, and I don't know much about bikes, so hoping you can tell me if I'm correct, or not, and clarify. Thank you! BTW, I'm asking because my bike runs great, but seems to be using way more fuel than it should

[@HTMR]

You need to watch this video since your bike has a fuel screw: kzbin.info/www/bejne/sJ6YnnVph52Imdk Now, if you want a lean cruise, find a pilot jet that nets you a fuel screw setting at 2.5-3 turns out. That will ensure a good idle air/fuel ratio, and the leanest cruise (1/8th throttle)

[@jonathansimmonds5784]

I always watch these video with the sound off, it tells you a lot.......!

[@randomstuffs1671]

Hello! I find your videos interesting. It's my first time to ride a bike, so i do not know much about motorcycles . I just have one question: do you mean that a carburetor has EITHER a fuel or air meter and not BOTH?? Thanks!

[@HTMR]

Whielly Bulfa Either, meaning one or the other. Here is a good read: www.howtomotorcyclerepair.com/how-to-size-your-pilot-jet-pilot-screw-explained/ Matt

[@johnnelson4260]

I’ve watched so many videos and they all talk about go through how many turns out for the pilot air/fuel screw, which you can usually find a starting point for in the manual. I understand this process, but what is the starting point for the idle speed screw. Everyone that makes videos is always working on a bike that already runs, and the never mention how many turns out the idle speed screw is or the process they used to get it there. They just already have it within the proper range and only talk about the fuel/air mix screw.

[@HTMR]

With carb off, hold it up to a light source. Open slide with idle screw until you see just a bit of light through it. That's a good starting point. Or just give it throttle while starting it.

[@DavidGonzalez-sx3db]

I need help I have the same bike I did it just like the vid .when in neutral it idles fine then when I ride it it bogs a lot

[@darkogligorov3181]

My the more it back in the more the idle increses so there is no beetwen like you said so eny advici?

[@Jorge-or3fr]

Great Matt!!! You got mi like and subscription! Matt, I have the same engine on a HONDA DAX 70 clone, made in China, by the way I live in South America. It is a brand new bike. A fellow here told me the same about the air screw 1 to 1 1/2 turn, the point is I still get kind of a black spark plug, the center is brownish as the aisalator but the rest, the thread is always black. Can not lean it any more since the screw is barely out totally. Can you tell me the correct RPM for idle speed once its hot, I mean after let's say 10 min of riding? Thanks Matt. Have a Great Day!!!

[@atulshinde5212]

Hi I also get same settings for my moped but honda Service manual says 1-7/8 turn out initial position then 4 turn out final position. How is that? I have 110cc honda moped or scooter. Plz share your thoughts

[@user-bw5le3xk9f]

Thanks. Before I adjust the air screw, how do I know I have the fuel idle screw in the best position? My 81 C70 Passport runs like something is holding it back and sometimes dogs down when I turn the throttle all the way. It should go up to 50 mph but only goes about 30. And it sort of chugs along, pulling like someone keeps yanking on a rope, then letting go. I hope that makes sense

[@voltage5607]

I don’t turn down idle all the way I turn it 3 or 2 times and it a bit loud but Idc

[@dougm.635]

so if im running rich (black-ish plug), do I want to back that out? same carb but Honda 50- only mod is a FMF pipe and someone drilled a large hole in airbox.

[@spritecrnbry9298]

At 1:53 what is that hose that is coming from the bottom of the carburetor for?

[@stepehnzavodsky3644]

Hey Matt I have a 1981 Honda Passport c70 with !200 miles sat for 36 years in a garage .Did the carb adjusted valves checked for vacuum leaks changed points and condenser still Boggs under load idles fine can't get it to go over 25mph. the bike was taken care of never messed with .Any suggestions Thanks Stephen

[@juanperez45554]

hey man you mind helping me out? i have a problem with my bike. when i turn it on, its like if too much air is going in and not enough gas.

[@HTMR]

Juan Perez What year make model and provide more symptoms.

[@StreetDisciple86]

I have an SSR 70cc Semi Auto. I've been struggling getting the idle just right adjusting my fuel and air screws. It runs great with the choke on but high and when I put it in gear it lurches forward. I've cleaned the jets and the carb/bike are both like new so I'm not sure what I'm doing wrong, I think I'm just having a hard time setting the screws just right being it's mainly guess work based off experience which I have little of when it comes to dirt bikes.

[@Cultofpersonality09129]

Your carb needs to be cleaned.

[@bonscott1938]

My friends sons XR70R stumbles under acceleration i.e it starts picking up but then won't rev out under full throttle, just splutters ( but doesn't die ) any suggestions welcome ?

[@HTMR]

Check for vacuum leaks and make sure carb is clean. Does it run better with choke on? What does the plug look like?

[@bonscott1938]

I put a new plug in for them because it had the incorrect one. I pulled the air cleaner cover off today and found the air filter was rotted. Cleaned car but it wasn't too bad. They bought it from a "friend" LOL

[@HTMR]

So is it fixed now?

[@steves659]

do you have a link to the pilot airbag video? thank you

[@miketrefry5839]

Hi there... I have a 2007 CRF100. I just installed a new Honda carb on my bike but I notice when the bike is idling and I instantly hold the throttle wide open the engine dies out. Any ideas on what the issue could be?

[@RORaulForward]

Hi, my kymco quannon 125 doesnt want to idle corectly. At cold, its ok, its stays 3200 rpm(automatic choke) and it doesnt fluctuate, not even 50rpm! But when its warm... Hell no! It fluctuate from 1200 up to 2100rpm, I've adjusted the idle, and it does this at any rpm, like if I set it to 1500 it fluctuate up to 2500... What can I do? Thanks!

[@HTMR]

Sounds like the carb is dirty, clean it and retune the air or fuel screw.

[@Darthanian0]

My kids have the 70 as well except it's a 06, seems to not want to idle in neutral, i managed to get the idle in gear nice, but that shift from neutral to first to brutal for a kid. Any tips? Already cleaned and put new jets and all carb, new plug and oil change it runs great just the idle deal is giving me grief. Bike has very very low hours, sadly.

[@WipedSik0]

Thank you for this tutorial, I have the same carb and I coulnt find any good video, even tho this vid is 8 years old, it helped me alot. Thank you.

[@bennytam5787]

Hi Matt , please help me... Honda cd70, new air filter, first 3km run well. after 3km, stop at traffic lights, the engine idling and shutdown by itself, or sometime run in slow speed the engine shutdown by itself too. Is it the fuel mixture setting not good? Or idling rpm too low？

[@HTMR]

Send me a video

[@bennytam5787]

@@HTMR Master Matt, According to your procedure to re set the idle and fuel mixture, the engine sound is apparently different, hope that can solve my problems, thanks a lot

[@changofeo9795]

I have a problem with my quad where itll be idling good, but for no reason it starts revving up. Is this a problem with the are fuel mixture or something else?

[@menaceperformance82]

Hi Matthew I have a quick question and wondering if u can check out my vid and me with my problem but when I have the choke closed the engine runs when it's open it dies

[@HTMR]

I commented on your video.

[@amvanquish5555]

Ok I need to know where and will this uni filter fit on my crf70? Will the crf50 uni fit one my crf70?

[@billymusick]

Good Morning Mathew..I pulled the carb off my sons '03 XR70...I have running like a top...but for whatever reason, I can't seem to get that throttle return spring to set properly...any tips? Thanks so much -Billy

[@HTMR]

+billmaa Once installed is it bunched up and buckling?

[@LightningZulu-cp6oh]

I just learned something thanks a lot

[@turbomini89]

Is the pilot adjustment procedure the same if it is metering fuel?

[@HTMR]

No watch this kzbin.info/www/bejne/sJ6YnnVph52Imdk

[@turbomini89]

@@HTMR Got it thanks!!

[@michaelmowery8933]

I have a karma 110 atv that’s blowing fuel out of the exhaust and smokes like crazy any suggestions?

[@HTMR]

Rebuild and clean the carb.

[@michaelmowery8933]

Thanks I bought a new one on amazon for 10 bucks today.

[@rushisharma816]

Hey my dirt bike is running just fine but it seems to run even when I’m not hitting the throttle! Is that because of the idle adjustment? Please help

[@masonsmith9876]

Hi I have a 2002 xr70 and it lacks in throttle response Amy tips

[@masonsmith9876]

And any things that I can but for cheap to help with power

[@HTMR]

+Mason Smith Email me here and I can help: www.howtomotorcyclerepair.com/contact/

[@coryseachrist8569]

+Mason Smith there is a screw in the bottom of your muffler take it out DONT BE SCARED it will be very load but up your power that piece is just there to lower sound anyway

[@leebrooks6464]

Wait, the pointy one is fuel? You can screw either on into either hole. Will it run like that ? Backwards?

[@HeidiFegles]

Your choke is on. This is pointless adjusting anything

[@HTMR]

@@HeidiFegles no it's not

[@sarahdavis3404]

Where do you start if you can't warm up the bike?

[@HTMR]

1.5 out

[@Educatefully]

1:43 we don't see anything. it's blurry

[@nicholaspanidis9722]

is your fuel on reserve?why?

[@user-bw5le3xk9f]

Thank you! Big help with my Honda Passport

[@blabaduplatinum1]

Nice job explaining everything.

[@p.c.h.6721]

Nice! Thanks, good video!! Easily explained.

[@JONSABMOTO]

you need to adjust that valve clearance. that clicking sound can break your bike overtime.

[@HTMR]

Valves are fine.

[@onassislegaspi2547]

Hi...I have a problem on my honda 50z carburetor air adjustment screw...I was totally strip the screw and I cant remove it...do you have any video how to fix the problem

[@HTMR]

No. Pay a machinist to mount in bridgeport and use LH drill bits.

[@firebirdjohnfiveseven315]

Theres a other screw on the other side by a black hose what does that do

[@HTMR]

Float bowl drain.

[@casualsofaracer]

Hi Matt, I want to ask u advise on this problem i have with the Mikuni TM40 FS Carb. When i adjust the pilotfuelscrew outwards and get to a certain point, maybe 2 turns and idle RPM is ok, then when i blip the throttle the engine runs off to 3+k RPM and cant get it down to idle again more or less. Need to push the kill switch. For me that looks like an airleak between the carb and the intake. But i cant detect any external with carbclean anywhere. There is a exhaustpop once in a while at idle, and when that happens engine stops immediately. I thought that when adjusting the pilotfuelscrew out, at a certain point the engine should get too rich and start to bog, but this here problem is really difficult for me.

[@HTMR]

What you describe is a lean hanging idle. Check for vacuum leaks and give it more fuel.

[@jamesa6272]

Yeah easy to do with one carb. Now what about 2 carbs. I’m going nuts trying to tune my rebel 450.

[@HTMR]

Multiple carb video: kzbin.info/www/bejne/en3PlaB4r9aFldU

[@jamesa6272]

@@HTMR Thank you very much. I learned a lot. I’m trying to jet and tune a rebel 450 with dual keihin cv carbs. I changed the exhaust and was told to run a larger slow jet and a larger main jet. I went from a 35 to a 40 slow jet and a 112 to a 130 main jet. I notice now at the factory 2 1/4 it calls for doesn’t run correct the revs hang high. I found if I screw in both fuel screws all the way the bike doesn’t shut off it keeps idling. It runs the best so far when I back the screws out to 1 turn out. Does that mean my slow jet is to large? And there is also a stumble at full throttle. Would that indicate the main jet at 130 is too big or small? The reason I did all this was because I’m running another muffler different than the stock mufflers. Still the same air box.. thank you in advance!

[@HTMR]

@@jamesa6272 What year bike? Have you checked for vacuum leaks? Did you vacuum synch the carbs? Doesn't make sense that it hangs revs when screw setting kinda says rich. That is a big jump on main (7 sizes). Have you messed with needle clip position at all? It would be best to email me here to discuss further: howtomotorcyclerepair.com/contact/

[@patk4929]

Thanks a lot dude! Helped me out a lot with my Kawasaki ksr 110 👍🏻

[@Technicalforeman]

1+1.5=2.5 Yaa > 1.5 Rotation ?????

[@ramrodskip518_7]

So I have an issue. My crf50 idkes crazy high, like bear rev limiter high, i have adjust the carb every which way and I’m not sure what to do

[@HTMR]

Remove air cleaner and see if slide is stuck open for some reason.

[@ivoallens6985]

But if u have higher idle isn't it easier to notice when the rpm's are higher??

[@MDboy5-o2k]

hi matthew.... i have hero 100cc bike i want to setting fuel screw setting. i was changed the fuel screw setting and now i am not doing back it's factory setting how can i do. how many turn the fuel screw for best performance and mileage 1 & 1/2 or 2.

[@HTMR]

+DEEPAK MATHUR You need to tune for best idle. Here is another video that will help: kzbin.info/www/bejne/sJ6YnnVph52Imdk Matt

[@chrissagredo7129]

2008 CRF80F. Probably like 5 hours on it max. Sat a long time, started, had to be on the gas or it would die and blew white smoke. Sat longer, just the other day it idled no choke, no smoke, but died when I revved it. Hasn't started since.

[@HTMR]

If it sat a long time, you have to clean the carb.

[@benevolentautore4463]

Any tips on a float adjustment/overflow adjustment? Can't get it to stop spilling fuel out the overflow tube on the 70 or CRF80.

[@HTMR]

kzbin.info/www/bejne/fpfReKyJZqafapI and here kzbin.info/www/bejne/Z3qciq1-gLtlrMU

[@gyanendrait]

Hey MatthewMCRepair nice video there. I am kind of trying to sort out jets on Mikuni round slide VM28 carburetor. It has air screw. So I start with pilot jet 25 the bike starts but idles kind of high and if turn the air screw CW then the idling RPM comes down slowly. So is that sign of lean pilot jet or rich pilot jet? Related to same issue above. If I do not bring down the RPM the way mentioned above then bike runs fine but if I do bring down the rpm the way mentioned above then the bike kind of gasp/sputter while running... So keeping both the above points in mind what would you say about the pilot size?

[@JeckDRippa]

Thank you so much for this knowledge! Just got a honda navi and carb looks almost identical. Did what you said and my navi is now back. Thanks again.

[@902trevor]

Thanks for the vid. My XL 175 now idles thanks to you.

[@rileymedina544]

Hey I have a crf50 with a 88cc kit and a a crf80 carb size carb and it ran amazing when I threw it on new and then the next day I can't even get it to start or idle and if I did it was really struggling to run but at full throttle it ran better can u please help

[@HTMR]

Email me here for help: www.howtomotorcyclerepair.com/contact/ We might have to share pics so I know what you have.

[@manojdavari1219]

Maine air fuel screw ko 1.25 rotation anticlockwise khol diya. To meri bike 70 ka mileage de rahi Hai.

[@carlmatischok2469]

valves need adjusting

[@HTMR]

kzbin.info/www/bejne/sKjXiWumotKjmJo

[@herschelkrustofski9830]

Thank you! Subscribed.

[@richardturner2781]

put new carburetor on 84 200m honda 3 wheeler hooked everything up gas pours out off carburetor threw butterfly needless to say wont run help please

[@HTMR]

Float needle is dirty or hanging up. Try tapping carb with screwdriver handle to see if that will help. Otherwise watch this video: www.howtomotorcyclerepair.com/how-to-pressure-test-float-needle/

[@codynautic]

Thank you sir. Saved my bacon 🥓

[@johnk815]

Thanks Matt. Under heavy acceleration my 70 has a lot of lag can you tell me what do you think that maybe I did change my air filter to a more free-flowing filter.

[@HTMR]

If you changed the air filter then yes you need to rejet the carb.

[@fahb68]

Hi Matthew son at the end all the screws meter air, one with the mix of the fuel and the other on the main ...? Great video it really help me out

[@HTMR]

The screw "trims" air to achieve proper idle air fuel ratio.

[@moisesenmoto.unlocoatodoga9605]

Hola. Tengo pregunta gasolina es sin aceite para esa moto ?

[@edselexie5761]

Hi Matthew, what could possibly be the problem of my motorcycle if it's idle rpm is unstable, going faster then going slow and go fast again? Carb is new and cleaned. Carb tuned already and fine tuned using your video guide. I am using idle screw and pilot air screw on this bike.

[@dmo848]

Vaccum leak maybe

[@klutchtls]

thanks for this man, got an 04 crf70 and it was idling real high. good to go now

[@RastaNate420]

Hi my 70rr when i ride alot of smoke comes out of exaust how can i fix that i have a video on it

[@HTMR]

Nathan Rochon Send me link to video. What color smoke? Black or white/blue?

[@RastaNate420]

White but smokes like a bitch ill show u this weekend tho

[@HTMR]

MatthewMCRepair Send me the video when you get a chance. It's probably pulling oil past the piston rings or valve seals. I have a full engine rebuild on a 50cc which will help you on your 70cc linked below. I also have the 70cc service manual for FREE download on my site: www.howtomotorcyclerepair.com/z50enginerebuild/ Matt

[@bretnagreen5003]

NJ Vlogs

[@Rodriguezerick23]

Does this work on a four Wheeler i can't seem to have mine where it stays on like I can turn it on and drive it but if I come to a complete stop and stop pressing the gas it just dies and in order to turn the four Wheeler on I have to have it on neutral and then push and put it in first gear so it can turn on back then I would have to jump start it and if I come to a stop and put on neutral it wouldn't turn off

[@HTMR]

What year make model? Does it have a carb similiar to the one in this video?

[@nicknak2950]

just bought a xr80 but it won't idle. I might have to clean out the carburetor but do you thing just adjusting the screw will make it idle?

[@HTMR]

Yes, adjusting the screw can make it die.

[@Erated78]

I have cleaned the carb on a 2004 Honda CRF100F. I've replaced the sharp-pointed pilot screw which you say is metering fuel but it's on the airbox side at the side of the bowl. The engine will not fire at all. When the plug is pulled, I have a spark and there is fuel in the cylinder. Is the carb set too lean? Do I turn in the pilot screw? Any help would be greatly appreciated! Cheers, Ed.

[@HTMR]

+Erated78 Ed, just checked the parts diagram and your bike has a fuel screw on engine side that is upside down. Start at 2 turns out and then tune it. Sounds like you have spark and fuel. How about compression? Plugs do get fouled so son't be afraid to install a new one.

[@Erated78]

+MatthewMCRepair Sorry, my error, you're correct the fuel screw is on the engine side and screws in from the bottom up. Compression is good. The plug is old and slightly black but sparks...I hear you though, replacing it would do no harm. I'll try the fuel screw at two turns out and see what happens. Thank you.

[@Erated78]

+Erated78 I turned out the fuel screw 2 turns, gave full choke and kicked to try to start, nothing. Then I put the carb to NO choke and it started!... but it runs rough. She seems to be running rich because there's a bit of exhaust smoke and not running smoothly. I tried adjusting the fuel screw to solve the rough running but didn't help. I also tried turning in the idle screw to keep it idling but didn't really want to idle. What do I do to get her to run smooth. I should also mention: the bike ran smooth under heavy throtle if that helps. Thank you.

[@HTMR]

+Erated78 Turn the fuel screw in to lean it out. Keep in mind it is upside down. Righty tighty. Have you checked the float height and made sure the float needle is sealing properly?

[@Erated78]

+MatthewMCRepair I did try turning in the fuel screw while running in an attempt to make it run smother but will try turning in more. Aside from inspecting and freely moving the floats, I have no idea how to check for correct float height. I have tested and can confirm that when the float needle is fully seated, the fuel flow is shut off...

[@mikenobbe1135]

have a xr100r put new carb on 22mikuni idles runs still bogs is it possible I need to adjust throttle needle

[@HTMR]

Bog is usually lean. How many turns out on air screw?

[@dang1456]

Thank for info Matt, I have a 1997 XR80 that I made these adjustments on. I found the sweet spot with the adjustments but the bike will not hold an idle. It idles perfect for about a minute and then will stumble and stop running if you don't give it a snap on the throttle. Any advice on this situation? Thanks, Dan

[@HTMR]

+Dan G How many turns out on pilot screw did you end up at? Remove plug after it stalls and let me know what it looks like.

[@robinj357]

I have a 19 mm Mikuni and I cannot get it adjusted. I've tried raising and lowering the clip on the needle, it only runs 3/8 throttle no more no less . Any guess would be much appreciated

[@HTMR]

Is it running rich or lean?

[@robinj357]

It seems to be running rich the jet has been drilled out slightly. I've tried 3 different Jets. Took the plug out and it was smut black

[@HTMR]

I'd focus on the pilot jet which is for idle. What size pilot and air screw setting?

[@robinj357]

I can get it idling like a champ ( 1- 1/5 turns +-) . I haven't messed with the idle Jet at all, just cleaned it.

[@robinj357]

What would happen if I open that idle jet up just a tad