Adjusting valves on my 2021 Yamaha YZ250FX - YZ250F, Valve Shims, Step by Step

Checking valve clearance video: • Checking valve clearan...
Helpful tools list:
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ProX Shim Kit 1.225-3.475 - amzn.to/3pbk3OH
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Digital Caliper - amzn.to/3sBeL1p
Oil Can - amzn.to/3pbsRnM
14mm hex head - amzn.to/3AQuNpE
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[@Jbren323]

This was definitely one of the best tutorials I have seen. Very easy to follow and I adjusted mine myself today

[@DirtBikingwithDonnie]

Awesome, I’m glad it was helpful for you!

[@deanmiyamoto6724]

No other videos on 2019+ yz250fx on maintaining the engine! I’ve got a 20 and so stoked you post your videos step by step. Awesome and keep posting all the work video you do on the 19!! 🤙

[@albertjgraham8]

Thank you for taking the time to make this video i tried watching other videos on adjusting valves for this bike and they did not go into detail like you did after watching your video i know exactly what to do so thank you so much

[@haydenmartin9386]

Thanks for making your video very easily understandable aswell as explaining how to measure for the right shims I was able to do mine in less than an hour and it started right up.

[@DirtBikingwithDonnie]

Thanks for watching!

[@fmtnic]

Excellent! I just bought a '22 250FX and will subscribe. Keep up the great content.

[@TwistedTriggerEnduro]

Appreciate you breaking that down and showing us how to get it done. 😃👍

[@DirtBikingwithDonnie]

Thanks for watching!

[@jonwoodworker]

Another great video Donnie. Next time, take the starter cap off and grease the bushing. It will start a lot easier.

[@DirtBikingwithDonnie]

Thanks for the tip! I’m going to do that asap.

[@RyanNew-m8r]

Awsome step by sept video did my 2020 yz250f valves adjusted with no issues .

[@TheMadMonkey3]

Whats the diameter size for the shims on that bike?

[@mattpotter2598]

Brilliant video. Changed my shims no bother following this video.

[@DirtBikingwithDonnie]

Awesome! Thanks!

[@markgunnison]

Great idea with the ziptie. I always mark it with something. Your method is much easier. Merry Christmas!

[@DirtBikingwithDonnie]

Thanks Mark. Merry Christmas to you too!

[@andrecasanova3753]

more I know about four strokes more I love my two smoker

[@DirtBikingwithDonnie]

There’s more complexity for sure. I have a couple of two strokes in my garage and I love those bikes as well. Thanks for watching and commenting.

[@dynamite5198]

This is gonna help me do mine here this spring before the summer hits!

[@mxcollin95]

Great video…def subscribing. 👍 Love how you get right down to business and don’t waste people’s time with a stupid intro and a bunch of talking at the beginning of the video like most “professional KZbinrs” feel the need to do. P.S. Technically, the only thing I’d say is that a lot of mechanics recommend doing the measurements on the TDC of the stroke where the cam lobes are pointing up and out (can’t remember if that is the compression or exhaust stroke). I forgot why that is the recommended stroke to take the measurement on but it might be something to look into if you’re interested.

[@DirtBikingwithDonnie]

Thanks for watching. I follow the service manual procedure, which is TDC. You can see the cam lobes facing up as I’m checking the clearances.

[@Randy_Cox]

Great video dude. Valve shimming seems pretty daunting till I watch you do it then it doesn't seem so bad.👍

[@DirtBikingwithDonnie]

Thanks Randy! It’s not very difficult with the right tools and some patience. Thanks for watching and commenting.

[@DirtBikingwithDonnie]

Just saw your kx250x video. Awesome bike! I was going to comment on your vid but you had the comments turned off.

[@Randy_Cox]

@@DirtBikingwithDonnie I didnt realize if you selected made for kids it would turn comments off.....so I changed it to not meant for kids and now comments are back open. Thanks for pointing that out.

[@NicholasBrownC]

Love the new plastics and graphics you put on there. I just ordered new graphics and plastics for my KTM. Decided to go for a black and neon blue theme. The orange had to go!

[@DirtBikingwithDonnie]

Thanks! I love a custom look no matter the brand. Thanks for watching.

[@matth8924]

If you're a weekend warrior (not racing) do you still need to check your valves every 20 or so hours? This video was fantastic!

[@wesleysriffle]

thanks for your videos. You have some of the absolute best videos for us shadetree mechanics. The links to the products in your videos help as well. You led me down a rabbit hole talking in one of the videos about gummy tires and about having a second setup for different terrain. What have your experiences been running gummy tires in mud? Thinking about getting a setup ready with AT81EX tubeless for mud races. The mud races in WV are brutally slippery and greay and every little bit helps.

[@DirtBikingwithDonnie]

I’ve found that gummy tires are great on wet rocks and roots but not great in pure mud. I would think the terrain in WV would be very rocky and if so a gummy should do well. They do wear out fast.

[@6Twisted]

What a ball ache just to adjust the valves. Gotta remove seat, fairings, air scoops, fuel tank, starter, head, cams and tensioner. On my 190 pit bike it's just 4 bolts to remove the head and adjust valves.

[@robertsarhanmd6433]

Excellent, Excellent Excellent video, you were very clear and I watched every step, Thank you so much, Robert

[@DirtBikingwithDonnie]

Thanks for watching!

[@fernandofernandez5719]

Thanks for taking the time to upload this amazing video

[@DirtBikingwithDonnie]

I’m glad it was helpful. Thanks for watching!

[@mauricemaltais1600]

Very good video, caméra always in the good place, very clear, calme voice with very good explanations best!

[@DirtBikingwithDonnie]

Thanks for watching!

[@rufus324]

I’m curious as to what’s going on to cause your valve clearance to get tighter? Shouldn’t it open up with time and wear?

[@waynereilly9750]

The valves tend to wear into the head which is why the clearances get tighter.

[@wesleysriffle]

Thanks for the video. What do you use to clean your aluminum? That bike is crazy clean.

[@DirtBikingwithDonnie]

Ecstar motorcycle wash. I have a video about my cleaning process coming soon. Thanks for watching!

[@danfan78]

Just completed this job on my 2020 YZ250FX. Couldn't have done it without your video and as with all your others they are great quality and don't waste any time. Have you considered starting a Patreon or adding an affiliate link to RM ATV? Thanks

[@DirtBikingwithDonnie]

Thanks! I'm glad the video was helpful. I am working on a way to sell shirts, hoodies and hats and hope to have that up soon. RMATVMC doesn't do affiliate accounts with small channels but I do have an Amazon affiliate account and will include the link here. Thanks for watching! www.amazon.com/?&_encoding=UTF8&tag=dirtbikingwit-20&linkCode=ur2&linkId=7d830ef5c90cf1950a5df42c37e1efdf&camp=1789&creative=9325

[@TheMadMonkey3]

Hey dude, whats the valve shim diameter size for that bike?

[@danfan78]

9.48mm@@TheMadMonkey3

[@jasongoodrich8914]

Great video. Have you had to do a topend yet and if so at how many hours?

[@DirtBikingwithDonnie]

I haven't. I sold this bike with about 140 hours on it. I purchased everything to do the top end but it never showed any signs of needing it (no power loss, no oil consumption, etc.) so I never did it. I have friends who have well over 200 hours with just oil changes and valve maintenance. I now have a 2023 yz250fx with 45 hours and haven't had any problems with it either. I have gotten this question several times lately so maybe I should do it just to make a video. Thanks for watching!

[@jasongoodrich8914]

@@DirtBikingwithDonnie Thank you. I've stayed away from the 4 strokes because I've heard that you need to do the topend after 25-30 hours. I might have to get one.

[@robertcadiz4346]

Great videos bro. I have a 2019 but this will help just fine. Thanks!

[@DirtBikingwithDonnie]

Glad it helped

[@SWATTracing]

Great video, thanks 👌 I have 1 small question re: cam chain tensioner, when you put tension back on the chain is there a setting, like a number of turns? Or is it just wound all the way out? Cheers from 🏴󠁧󠁢󠁳󠁣󠁴󠁿

[@DirtBikingwithDonnie]

It’s tensioned by a spring so when you release it, it automatically springs back to where it should be.

[@andreyzastavskiy944]

I really wish they’d come up with a way that a regular person that’s not a mechanic could just ride forever and not have to do an adjustment every 20 somewhat hours. Or make it somehow that you don’t have to tear apart half the engine to do it.

[@andreyzastavskiy944]

Great video btw. It really made me understand how to do it. Not as scary now.

[@DirtBikingwithDonnie]

They are very reliable engines. Some people run them for 150 hours or more with just oil changes. It's a high-compression engine that will rev to 14k and produce 42 hp so there are some maintenance trade-offs with that kind of performance. How you ride it will also determine how often you might have to do valve maintenance. If you stay off the rev limiter it will stay in spec a long time. It can be intimidating but the shimming process isn't difficult if you buy the right tools and take your time. Thanks for watching and commenting!

[@mischi7920]

On the Intake are the valve specs 0.10 - 0.17 mm as the manual say. If I have to adjust it is it better near or to 0.17 mm, or near 0.10 mm?

[@matiasmaldonado510]

Wow you're a great bike mechanic, love your videos, I have the exact same bike as you, I already put 73 hours on it and I haven't checked the valve clearance at all, the bike feels great to me, did you feel any difference because the valve were a bit of clearance, or you just doing it by hours, what could happen if I don't check mine?

[@DirtBikingwithDonnie]

Thanks! The most common symptom of tight valves is difficulty re-starting when the engine is hot. Although these bikes are sometimes hard to start when hot regardless. I had started to notice mine was getting a little harder to start when hot and that’s better since I adjusted them. I have friends that have similar hours as you and haven’t checked theirs either. I’m a little more particular about mine and I like to check the clearances every 25 hours or so. Thanks for watching.

[@matiasmaldonado510]

@@DirtBikingwithDonnie thanks for your your great videos, now I have an idea how to adjust the valve clearance on my bike. One more question, I would like to install the yahama lowering link on my bike, which I've heard is gonna lower the bike one inch, but I can't find a bar riser to adjust the forks, do you think is ok to do that, and where can I find risers for this bike, thanks.

[@DirtBikingwithDonnie]

@@matiasmaldonado510 Here are some bar risers that might be what you're looking for. amzn.to/30WxmJC

[@slab6993]

Great video, very helpful 👍

[@mischi7920]

I have on my WR450F 2022 Intake the specs 0.10 - 0.17 mm as the manual say. My Intake valves are now on 0.11 left and 0.13 mm on right after 150 hours. Should I adjust it to 0.15 mm or is it o.k.? The Exhaust valves are in spec.

[@DirtBikingwithDonnie]

In my opinion it’s ok as long as it doesn’t go below 0.10. You’ll need to check the clearance regularly to see if they are getting tighter. Also, the engine will become hard to start when warm if the intakes get too tight, so that’s another sign they need to be re-shimmed.

[@mischi7920]

@@DirtBikingwithDonnie Thanks for the answer. The bike starts without problems, even when the engine is hot. But since I have dismantled everything anyway I thought that I re-shimm right now before I reassemble everything. Then I am for the next 100-150 hours on the safe side. I've never done anything like this before and with your instruction I should do it sometime.

[@bryantmcguire954]

I have a 2021 yz450f and it’s beginning to have a hard time starting and idle when cold

[@bakergilbert]

Ya great video but does 2/100’s of a mm really make that much difference?

[@DirtBikingwithDonnie]

I mentioned in the video the reasons I was going ahead and bringing them back to the middle of the spec. Also, this video has paid many race entry fees, so yes. Thanks for watching!

[@bakergilbert]

I hope my comment didn’t come across as negative. It is a very good video. Details, clear and concise, and it seems you cover all that is important. I’m sure I’ll refer back to it when needed. Thanks for posting.

[@DirtBikingwithDonnie]

@@bakergilbert No, I appreciate you watching and commenting.

[@largejoseph7914]

Great video, super helpful

[@spencerstokes8630]

What socket did you use to take the spark plug out? I’ve tried 2-3 different sockets and they are too thick.

[@DirtBikingwithDonnie]

14mm regular deep socket. Spark plug sockets are too thick.

[@spencerstokes8630]

@@DirtBikingwithDonnie thank you sir.

[@abdullahshahid6637]

When should we adjust tappet clearance? How do we know that it's time to adjust tappet?

[@DirtBikingwithDonnie]

It’s a good idea to check the clearances every 25 hours or so, but if your bike is having difficulty starting when hot, that can be a symptom of insufficient clearances.

[@diggybean2705]

Awesome video thank you

[@fernandotorres1383]

Do you have to drain the coolant befor taking off the valve cover I mean

[@DirtBikingwithDonnie]

No, you do not need to drain the coolant.

[@chuck478]

Just wondering with the spark plug tube, does that just pull out? My old spark plug was filthy as well as the inside of the tube I just want to clean it out

[@DirtBikingwithDonnie]

I've never tried to remove it. There is a drain hole at the bottom of the tube that drains out of the right side of the head. With the spark plug installed (to keep anything from getting in the cylinder) you might be able to flush it out with some parts cleaner.

[@chuck478]

@@DirtBikingwithDonnie ah yeah thank you, I’ve seen on other bikes leaking rusty fluid down there from that hole that makes sense thank you

[@austinhorna124]

When do you plan on doing a top end?

[@DirtBikingwithDonnie]

Good question, I’m not really sure. Yamaha says new piston and rings every 12.5 hours which seems ridiculous, but I’ve heard of people going 300 hours so I’m not sure when I’ll do that.

[@austinhorna124]

@@DirtBikingwithDonnie Same thoughts.

[@SAGEpresent]

Great stuff

[@BlueDawnEnduro]

great video!

[@DirtBikingwithDonnie]

Thanks for watching!

[@craigbowers4047]

Leaded fuel will slow down valve seat erosion.

[@DirtBikingwithDonnie]

Great tip, thanks!

[@fernandotorres1383]

When checking valve clearance do u have to drain the coolant befor taking the head off

[@Lastofthebigswinging]

No dont have to drain anything including engine oil.

[@ypcchino459]

Very helpful

[@Lastofthebigswinging]

Great video best I've seen? Let me ask anybody have hard starting when bike is normal operating temp? I heard this was a characteristic but not sure tried lithium battery still slow starting 2020 yz250fx

[@DirtBikingwithDonnie]

Thanks! Yeah, it’s a common issue on the 2020 and up yz250fx. How many hours? Clutch drag can be an issue with the stock clutch. Do you have the problem when in neutral? Otherwise a Antigravity AG-801 battery and raising the idle to 2,500 helps a lot.

[@Lastofthebigswinging]

@@DirtBikingwithDonnie Slow starting Donnie especially slow in gear. (probably 150hrs) Let me ask you replace the valve cover gasket with new once removed or any sealant?

[@Frank-i-e]

Hello! I was wanting to get some help. I took my bike down and checked the clearance because at constant throttle or using the cold start switch the bike sounds like it’s breaking up. I bought the bike used and never had a Yamaha but I’m unsure if that’s normal and I’m just being picky. I figured even at constant throttle it shouldn’t make any weird difference in exhaust sound but I’m unsure. I got my valves back in speck and put in a new plug. If I’m climbing RPM it sounds normal just not constant. Any ideas if that’s normal or not. Thank you

[@Frank-i-e]

The bike has 17:36 hours

[@DirtBikingwithDonnie]

I think what you’re describing is normal if I’m understanding it right. Does it run normally when riding?

[@Frank-i-e]

@@DirtBikingwithDonnie as it’s climbing in the RPM’s it’s clear and everything sound great. As soon as the bike stays at a constant RPM it sounds like there is a faster exhaust not almost like a launch control on a race car if you will. I will try to get a video.

[@Frank-i-e]

@@DirtBikingwithDonnie i just uploaded a video. Would you be willing to take a look? You can hear it change sound at constant throttle. Just wasn’t sure if that sounds normal or not. Kind of like it sounds it revs and sounds closer together or something. Thank you so much!

[@DirtBikingwithDonnie]

@@Frank-i-e It sounds normal to me but I can’t tell what you’re doing with the throttle in the video. Nice bike!

[@whphboys_tv8593]

Thx you

[@TheMadMonkey3]

Whats the valve shim diameter size?

[@wesleysriffle]

Are the shims magnetic? Just stick in the bucket?

[@DirtBikingwithDonnie]

I was using a magnet tool to remove the buckets. The magnet holds the shim to the underside of the bucket. Oil will also cause the shims to stick to the bucket so if you’re not using a magnet you have to be very careful to not drop the shim.

[@Olicoate]

Vernier calliper 😬 micrometer 😏

[@Totone101]

Great video!