I have an 06 yfz and I am the orginal owner of it and i was wondering if anybody else who has a yfz is having a problem with it burning oil? I changed my oil and rode the quad maybe 20 hours with after the oil change and the other day the whole top end blew because of no oil and there was no oil leaks. Just wondering if anybody knew what might have happened?

 

There is a screen in the botton of the wet sump resivor, and all the YFZ's I have seen have had some shavings around this screen,from break in off the machined parts internally in the motor, have you ever taken it off and checked or cleaned, it is in the line that returns oil to the engine. Unfortunattley there are a multitude of guys who have 04-06 YFZ's that have had the wrist pin seize up on the crank because of a poor oiling system these motors had, yamaha changed to a much better system on the 07 and newer, but never took the blame for the earlier years.

 

No. I haven't taken off that screen but thats where it broke was at the wrist pin and tried going threw my cylinder and now everything from there up has to be replaced.

 

That is what they do when they seize, I feel for you. 2 of my friends YFZ's did it with-in the first year they owned them both were 05's, Mine is still going strong. After there blew, I started changing oil and filter every 8 hours of riding.

 

Oh well mine i has a lot of hours so it was getting close to where it needed to be rebuilt soon and only one of my friends has had problems with there yfz and it was something with the oil while he was racing.

 

If you have that motor rebuilt your lookin at 1500 - 2000 depending on how much damage it done, normally if they blow will you got the trottle pinned, they destroy everything, if you were just puttn around you might not have screwed it up completly. After the rebuild I would only suggest oil changes in the 10 hour window time. Amsoil Thumper is some of the best you can get.

 

Ya just for parts its around $1600 and half of it is aftermarket stuff and then my friend is rebuilding it so labor isn't gonna be anything, but would you consider getting a used head and having it port and polished?

 

The only thing I would see is if it is head out of a blown up motor, if not as long as it is flat where it seals aginst the top of the case it would be fine, be picky on who does the port and polish, and have the valve seats all reground. Serdi Cut is the best and most reliable grind to do. Going with OEM valves, springs, seals and seats will be your best bet. Yama's OEM valve train is better than aftermarket and normally cheaper.
If interested I actually have a 05 head that is off my old stock motor, not a thing wrong with it, I just put a full race engine in my bike to race XC and don't need it. I have a bunch of motor parts for 04 & 05 YFZ's. Sorry but I have sold the crank to a guy who blew his up. Let me know if you need anything, I may have it. I am in South East Ohio
1-740-438-7883 or 1-740-767-3796 evenings

 

How much do you want for it? and is it complete?

 

I have everything for it but it is disassembled, which is good if you are going to have a port and grind job done for it.
consists of the following
1 head
1 Ex Cam w/ towers
1 In Cam w/ towers
5 Valves
5 Springs
5 Valve buckets ( no shims )
1 Valve Cover
all bolts associated
$300 shipped OBO
call me if interested and I can get you some pics 740-438-7883