top and bottom kit ?

I bought my '09 450f last year off a guy who raced VET A. Despite his racing skills he lacked maintenance wise because when buying the bike I saw he neglected it (filthy air filter and oil was filthy as well) among other things. He said he had a new top end installed with only 8 hours on it but I was still able to negotiate the price way down because of lack of maintenance.

My question is though should I just do a complete rebuild for peace of mind? I've only put another 20 hours on it, I just wonder if it's really more hours on it than what he says and with the way it was maintained would I just be better off buying like a Wiseco Complete Top and Bottom Kit and Cam Chain for 600$ online and having my mechanic do it? (I'm def not doing it myself) I know Yammys' are bulletproof but I just constantly worry about grenading and whether or not he was honest about the hours.

Do not use a wiseco crank ever. I would just measure out the tolerances and go from there.

Do not use a wiseco crank ever. I would just measure out the tolerances and go from there.

What's wrong with Wiseco?

What's wrong with Wiseco?

Their cranks routinely fail in a few hours.

Wiseco cranks as of last year were of Chinese manufacture. They had and may still have various quality issues to include being well out of true when shipped, failing to conform to factory balancing standards, and poor rod bearing life.

Hot Rods cranks are Taiwanese, and are a higher quality piece of work, although they still fall somewhat short of the OEM crank.

If it were me and my bike, I would have it rebuilt. It's been my experience that when a part, or parts, gets in your head as potentially unreliable, it'll never get any better until its replaced or repaired. It may not have failed yet, but I would bet you ride differently because the mechanical dependability is questionable. Peace of mind and knowing you can depend on your bike changes a lot mentally. That's just my 2 cents for what it's worth.

If it were me and my bike, I would have it rebuilt. It's been my experience that when a part, or parts, gets in your head as potentially unreliable, it'll never get any better until its replaced or repaired. It may not have failed yet, but I would bet you ride differently because the mechanical dependability is questionable. Peace of mind and knowing you can depend on your bike changes a lot mentally. That's just my 2 cents for what it's worth.

I couldnt agree more. It clould go another 100 hours but I will just be worrying wondering how honest the seller was. I guess ill have my mechanic look at it but how much can he really tell?

I couldnt agree more. It clould go another 100 hours but I will just be worrying wondering how honest the seller was. I guess ill have my mechanic look at it but how much can he really tell?

If your mechanic is any good he will tell.

What you should be asking yourself is whether your mechanic really is up to it, judging by your above statement !

I trust him. He's a young guy mid 20's that owns his own shop. He's a little young but the fastest riders and do it yourself guys around here have no hesitation taking their bikes and quads to him when they cant do it themselves.

Someone earlier said check the specs. So he can measure whether or top and bottom need replacing? Will some explain please explain this beyond owners manual language?

Wear at the rod bearing/crank pin, and the condition of the bore/piston are both measurable and quantifiable. What cannot be judged by any means is how much time a particular bearing may have left before it starts flaking pieces off the races/balls/rollers (spalling). That sort of thing is all guess work even with experience. The spec section of the manual shows how the measurements are to be taken.

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