Will It Start? - YZ250 Top End Rebuild (Part 2)

With the barrel redone, it's time to finish up the top end rebuild on my Yamaha YZ250 and install the new shift shaft BUT will it fire up?
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[@ruthlesstrades2184]

A nice way to remember where different sized bolts go if you're dealing with many parts is to stick them in a piece of cardboard in the same pattern as to how they secure the part they came out of.

[@jessevvilsteren]

Gotta love the feeling of the first start after being on it for so long. Last time I had to rebuild my Honda NSR it turned over great, gave it a little throttle after the heat cycle's and bang it went. Gotta start from scratch all over again. But hey nothing beats the feeling of it starting again

[@thanatos5329]

My prayers have been answered

[@331moto]

Yikes on the impact to tighten the clutch basket nut. That nut should be torqued to spec with a torque wrench. My CR250R is around 50-60 ft-lbs. Put the bike in 3rd or 4th gear, stand on the rear brake to keep the basket from turning and torque to spec.

[@vega4459]

You don’t need it to be torqued down to work correctly. It’s just an extra step as insurance but it’ll be fine as long as it’s not loose.

[@331moto]

@@vega4459 torque values are determined for a reason. An impact gun will never be ok to use on an aluminum housing motor..

[@harrisonjacobsen173]

As someone finding my way through dirt bike maintenance too, I have come to love these videos. Cheers from Seattle, keep them coming!

[@sarahsmith1575]

You should have went with a Wiseco piston

[@yoshuavillar]

11:01 this moment is totally relatable lol, but the outcome was really satisfying chaos!

[@smartgarage8886]

Excited for the lectron carb 😄

[@bjornzorger3731]

Perfection bru ,well done ,exactly the kind of yz250 video i wanted to watch .

[@pejal1308]

This is so satisfying to watch.

[@AVeryBritishBiker]

Yep circlips are great fun. Just done a top end on a little 50cc 2stroke scooter and the piston on that is tiny and so are the clips. Worst is when they ping off somewhere. Luckily like you I have a nice clear floor so not too hard to find them but still a pain

[@Zepplin76]

Yesterday I went to subscriptions to check how I'd missed a video since it felt so long.. Glad it's running well and envy the accomplishment you feel.

[@B18CXr]

Great video/update. Music is 👌 too 🍻

[@BrianPhelpsV2]

2-strokes and dirt are so much fun. And forgiving. I followed a similar path replacing all the things wrong with my 2-T mx. I replaced the exhaust valve assembly (which was dissentigrated into several parts), all the gaskets, and aluminum bolts. The bike ran exactly the same but with less splooge. What made all the difference was replacing the piston, reeds, re-jetting, and carb boot. Re-jetting because previous owner thought new aftermarket pipe = instant HP. Stock jetting needs a stock pipe. Just don't pipe it otherwise lol.

[@pascalw.paradis8954]

You did a good job on the fix ! Your wrenching powers will increase.

[@mxJAY19]

When you changed the shift shaft, the side had came of the bearing that connects to the rod and has fell down on the rod that goes to the spring look at 5.33

[@CityDrivingSchoolInc]

great cinematography!

[@toddhickox4757]

Great job !!! Beautiful Bike ! Gotta love a YZ !! ❤

[@lukabordon2781]

Best content on youtube I love your yz i've been waiting for this video so mutch. Keep up the good work💪

[@motodeer]

Your videos are awesome, and are helpful, keep up the great work!

[@jugurttipurkki9772]

in future you should try vertex pistons. they are very good and durable

[@christopherhall2107]

Enjoy the ride! You deserve it 🤘

[@nastysoda9212]

Was really excited for you when it started right up, nice job!

[@jktho]

Brilliant job. And sexy camera work. 👌

[@michaelmiane9377]

I was waiting for this content...👌

[@arjithar4872]

Bro 6:40 its kinda recommended not to use metallic things to remove the remaining gasket but still excellent content bro

[@4fiddy_a_aron]

Nah, as long as you're careful, razor blades are the best gasket removal tool

[@arjithar4872]

@@4fiddy_a_aron Still plastic ones are considered better since they don't cause scratches which can cause leaks as the new gasket wont be seated properly so.......

[@4fiddy_a_aron]

@@arjithar4872 I see you probably haven't had to remove that many gaskets in your life...

[@jarnobovendorp7908]

@@4fiddy_a_aron In my opinion, he kinda has a point. While you can remove remaining gasket with metal, I find it better to use plastic to minimize any risk of schratching the surface. But metal would also work when careful.

[@joshuavanzuydam5044]

@@4fiddy_a_aron As someone who has removed alot of gaskets. Always use plastic or Rubber. A razor may be better, but Scratches are a real issue for seating

[@terryboyle]

Love this kind of content!

[@alexcrafter_]

My dad bought an old cr250 off of a friend of mine, it had its top end off and a rag stuck in the bottom end. My dad has assembled the top end with a Wossner piston. Hopefully bottom end hasnt got any leaks 🤞

[@quadeericsson8122]

hey mate, not the biggest deal ever but you put the cylinder studs back in upside down, rounded end sticks up, flat end is meant to be down in the cylinder.

[@jimtoone1777]

Best not to forget that sulphur in fuel will deteriorate nikasil in engine linings

[@jerryjannink46]

Check your shift stopper 5:28 the bearing is broken…

[@jameselias9399]

Awesome video

[@harro9447]

That's great 👍

[@dmartinr41]

most awaited video of the month

[@Jack-kg2qr]

finally i have been waiting for this since the last video

[@Toxic88088]

If the shift shaft is longer than needed, it'll bend on aggressive shifts. A sign of that would periodic wear of the shift-shaft seal. A major problem in KTM's. Formula390 makes shift-shaft support with needle bearing insert for the 390's. See if you can get someone to make one for your YZ. After all you do ride it hard around the track.

[@knaaxi]

Could you please provide a link to the service manual you used, would come in very handy in future repairs on my yz

[@DeanosRides]

Good job mate! Well done!

[@T.J.C.07]

Yes! new vid.

[@off.coast.gromer5940]

Lectron carb i just know it the coolest upgrade he is putting on i a lectron carb i think

[@nathandyess5310]

It'll be a SmartCarb. Much better carb than the Lectron.

[@pawekrukar6034]

Nice Job 👌

[@jamiesonfilmz3994]

Not as bad as my yz blowing a hole in the piston and play in the crank

[@kdcustoms1272]

Thanks for sharing.. Sub'd love my yz250.. Sadly it needs a new bottom end 😞

[@olehyrole8535]

It will get a lectron carb!

[@SmartCarbFuelSystems]

Nope, even better!

[@disekjoumoer]

You mentioned the holy grail of motorcycle maintenance: the service manual. Without that, it's guesswork and badly filmed youtube videos from 2010.

[@tomasdooley4285]

Congrats

[@srdjanmatic7099]

Whait, don’t you need to put piston in the most top position when installing new? Or it can be anywhere? (Asking bc of firing cycle, does the piston need to be in specific place for it to fire as on four strokes or not?)

[@radodanchev8600]

How are your hends so clean

[@craigsteinman9807]

We're on cylinder do u find the letter stamp of cylinder..A B C OR D?

[@marselrihtaric3734]

Does that mean youre geting another project bikee??🔥

[@TheRealKlinky]

Hey dude, where did you send your cylinder for re plating? You in SA?

[@78raarons]

Did that oil draining look a little milky? Or is it just me... F those circlips

[@OnlyCitrus]

Is this the same engine used in the FZ25?

[@travisk5589]

3rd kick, just like every other well running yz

[@Soltero1595]

Cool upgrade? Turbo YZ?? :o

[@chrisnik1142]

How did you even remember where some parts go to thats my question

[@TheHortond]

You call a wrist pin a gungion pin. But you call headstuds by the name I use. I thought for sure it would be called dublydoo or something. Cheers. I get more culture from KZbin than I do from school.

[@gangstagrunt0190]

What’s the song at 9:59?

[@NoPro420]

woah congrats! didnt think it would run..😂😅

[@sebastiaanvandermerwe4887]

Hey Chaos, where did you get your cylinder replating done ?

[@streetwiseburger]

NSC Krugersdorp

[@catfish_lude]

afkans haha my boi

[@uses0ap]

9 years ago I posted a video for personal use with no intentions of anyone watching it-- Come to find out, you had made a kind comment on it. Thanks. Lol

[@midlifeduck7040]

Does this project make you wanna get a project bike? You could fix it up. Maybe sell it. Or why not try auctioning it off. You could donate the proceeds to a charity that you support.

[@goten3265]

Nice broi

[@greatest_bumble_bee_dude]

Why would you waste time on rebuilding only the top end of the motor. I would highly recommend to rebuild the whole motor including The Conrod kit seals And yes even the main bearings. Also : IT sounds like you're not placing enough oil mixture. You're supposed to place roughly 200 mils Of 2 cycle oil in each 5 litres of petrol. The bike companies Will advise you to place Less. Not a good ideas. Also : would recommend to Run in the engine slowly to 4 fuel tanks instead of just 2 tanks like the bike shop employees advise

[@pepijndekoning3727]

oil your damm gaskets

[@ajeet.islost]

Hey chaos

[@bayley1587]

First

[@streetwiseburger]

Shame

[@beemaltamang5939]

Damn I'm early. 😂

[@brumle0660]

How are you?