My new toy...inside!!!

so what does a yfz cost to rebuild? say cylinder, cam, and redo the head??

good find man....hope theres not to much wrong with it. Parts are high dollar for those bikes, believe me i know, ive got 2 yfz lol

for what you paid you could find a take off motor from a 450 and still be money ahead. Just get an 07 or later.

when you get it running be sure you change your oil VERY frequently... And stay away from synthetic oil while your breaking it in.. (if you get a new piston) which would probably be a good idea if your already in the motor.. and vary the throttle not keeping it at a certain RPM... 450s can be extremely reliable if you take good care of them and keep the motor stock. I love my ltrI:I

I've also got a 2005 I picked up earlier this year. Mine didn't have the oil mod for it's first 5 years and it still runs great.....though I just did the mod as extra insurance. J&T ATV offers the mod for ~$200 on ebay or directly through his website. So pull off the outer case cover on the right-hand side of the motor and check if you've got the mod done or not.....prolly not. You can go to YFZCentral.com or other sites to read up on the specifics of what the mod is all about and what to look for. Seems hit or miss whether the 2004-2006 quads will need the mod, but having extra oil squirting onto the piston's wrist-pin can't be a bad thing.

Hopefully you don't have to do much to get it going. I have a pdf of the service manual, so PM me your email address and I'll send you a copy.

If you do get it going, there are a few cheap and easy mods you can do like 'zip tie mod' to eliminate throttle hesitation, 'cam mod' for instant power gains and 'throttle spring mod' to aleviate thumb-throttle resitance.

If it doesn't have a case saver, get one imediately. Just more cheap insurance against a costly repair.

Mine's piped, jetted, no airbox lid, and after market dual-stage airfilter and it practically rips my arms off when I pin the throttle. I call it 'the beast' because the power seems endless and the limits of where you can go on a yfz become solely a factor of the rider's desire & ability.....and not the machine.

Good luck!

another issue with those early models is in the oil tank there is a metal screen tube around the end of the pickup tube which sends oil to the pump. It WILL get clogged up with debris, especially if it has a stock air filter and especially if it was being run with no airbox lid with a stock filter. This screen needs to be cleaned about every 3-4 oil changes.

look here

ATV Riders Forum - This is why YFZ's have oiling problems