Solving the metal in the oil issue

I took the advise of one of our members after reading his thread concerning his problem that sounded similar to my problem with metal in the oil filter. Along with metal in the filter, I had this pulsation sound coming from the engine. He recommended replacing the big end bearing on the crank. I did this buy replacing the crankshaft with a new one from Yamaha. Bingo, the problem is gone. No metal in the filter and no metal in the filter. What a genius

What kind of bike do you have? How much money did it cost for the total job?

Sounds like you had a more serious issue! I've had metal in the filter since day 1 in year 2001; if the big end rod bearing had been failing all that time I think it would have let go by now. :applause:

1998 YZ400. I did all the engine work myself. The cost of the parts from Thumper OEM was about $350.00. (but If you asked my wife it was under $100.00). I had the old engine crank torn out, reinstalled in the bike and fired up in about 6 hours, from start to finish. The bike is a piece of work and easy to to maintain. I ran it out in the desert last weekend, (by the way, it was 74 deg. for all of you that might be freezing this time of year) put about 100 fast miles on it, pulled the filter and only found rag fuzz. It will be good to go for many more years to come.

Riding area-Plaster City West

Yz 400

15 front and 44 rear sprocket

50/50 avgas and 91 octane

Did the 98' have steel or aluminum plates in the clutch?

That wasn't as much money as I thought. TT must have some good deals.

The 98's have steel plates. When riding in the desert, you very seldom use the clutch anyway.

I took the advise of one of our members after reading his thread concerning his problem that sounded similar to my problem with metal in the oil filter. Along with metal in the filter, I had this pulsation sound coming from the engine. He recommended replacing the big end bearing on the crank. I did this buy replacing the crankshaft with a new one from Yamaha. Bingo, the problem is gone. No metal in the filter and no metal in the filter. What a genius

That would be moi :bonk: ... and you are welcome.

The only thing I would have done differently seeing that you put a new crank in, is I would have replaced it with a 426 crank (bigger diameter small end-19 mm) which would have allowed you to punch the sucker out to 444 cc. This is what I have done on both my 99 WRs. Anyway, enjoy the bike with the rejuvenated motor :applause:

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