Engine Overhaul

Hey 4-stroke experts Im getting a basket case 01 yz426f with a blown bottom end for cheap! it has a baja kit and a legal plate all the parts are there and i dont know where to start. Roughly how much is it gonna cost to rebuild? I think I do the work my self or find a family member who can pull some favors. Should I tear down the top and bottom ends or just the blown bottom end? (not sure what is "blown") Where should I start? Is it worth the hassle?

Cheers

blown....thats kinda vague...Start disassembling ,replacing damaged parts..

Teardown the whole motor and rebuild/replace any worn or broken parts. Use stock yamaha parts and the motor will be as reliable as when it was new.

A four stroke of that age is probably not worth rebuilding. Too many expensive parts, and those parts are going to cost more than the completed bike is worth. You are better off parting out this bike on ebay, and finding another project.

A four stroke of that age is probably not worth rebuilding. Too many expensive parts, and those parts are going to cost more than the completed bike is worth. You are better off parting out this bike on ebay, and finding another project.

You guys act like its a friggen dinosaur. Its only an '01, and if he gets it cheap enough, then go for it.

My question to the original poster is WHY? Why did the bottom end blow? If it's something like lack of lubrication, then you can expect to be replacing the whole valvetrain and piston, and getting the cylinder bored/replated or replaced as well.

i've got an '01 that runs like a champ with very low hours on it but......i'm thinking i'll be parting it out....nobody's biting on it and like the other guy said....worth more as parts than as a complete bike.....figure on $2,000 to replace a blown motor....i asked 2500 (kinda high i know) obo and only got two calls and one tire kicker....

It would probably run you around $500-1000 depenging on what needs replacing (I rebuilt my old 426, and it ran $700 for a new gasket set, crank, bearings, and a few other misc. parts from TT OEM). If you do it yourself, you'll save a lot of money, since labor is where the astronomical costs incur when rebuilding a 4-stroke. When you reassemble it though, be careful you torque everything properly, and double and triple check everything.

I would think you would be able to rebuild nicely for 1200.00.....top end, head, crank...this is providing you dive in and do the majority of the work...

well a mx bike with a plate is costs around 1000$ if you can get it in california and im getting it for 800$ I recently heard the whole story on the bike. The bike was putting out alot of blowbuy and was using a unusual amount of oil long story short the the bike was ridden a "couple" miles with very low oil and now its a basket case. The cylinder wall has a little scar in it and ill probably have to bore or sleeve it. Any ideas on whats "blown"?

CHEERS

If you decide to rebuild, I would def. go with the lukes 444 big bore. Its reasonably priced, and will run with the 450's. Never done a bottom end, so I cant help you there...

you said ur gettin a basket case 426 are you getting the whole bike? im in need of a couple parts here and there so let me know thanks

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