'03 yz450f questions and concerns


5 replies to this topic
  • brolo747

Posted June 21, 2007 - 09:46 PM

#1

I just bought an '03 yz450f. I did all the maintenace that hadn't been done in a while ; oil change , sprockets and chain, brake fluid, greased cables etc etc... :thumbsup:

I was curious though are these bikes normally really clattery at idle??? Or do I need to do a valve adjustment???

The only other thing that is tripping me out is that whenever I put it in gear and pull in the clutch it chugs me foward... or just stalls I have tried adjusting the cable to fix this but have had no luck any idea???? Currently the cable is almost all the way slack.:thumbsup:

  • grayracer513

Posted June 21, 2007 - 09:52 PM

#2

If you are saying that you increased the free travel to get rid of your clutch drag, you went the wrong way. Set the play to the minimum and see if it helps. Otherwise, you've got unevenly sagged clutch springs, and/or warped and worn plates.

The YZ450 is noisy, but the only way to know if it needs a valve adjust is to check the clearance and see.

  • 03yz450f-43

Posted June 22, 2007 - 03:24 AM

#3

When I got my 03 450 it was noisy too. I was told by the previous owner that the motor was fresh and everyone told me that these bikes were noisy and not to worry. I was also told that these motors hit very hard and the power was almost uncontrollable. I did not find that the case. After a catastrophic shut down right before a 60 ft double (a few more feet and I would have been toast), I found that my timing was off a tooth and the piston was hitting the valves. The motor was fresh, but put together wrong. I had to replace valve and componets, timing components, pistion, etc. My advise would be to have an experienced mechanic take a look at your timing to make sure. My bike is still a little noisy, but nothing like it was and it does hit very hard now.

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  • aaroncmh

Posted June 22, 2007 - 04:17 AM

#4

The only other thing that is tripping me out is that whenever I put it in gear and pull in the clutch it chugs me foward... or just stalls I have tried adjusting the cable to fix this but have had no luck any idea???? Currently the cable is almost all the way slack.:thumbsup:



I have the same bike and when I first got it this freaked me out too. All you have to do is make sure it's warmed up and before the first ride of the day pull the clutch in and out a few times before putting it in gear.
I think this gets the oil all in/around/through the clutch and after this it hardly lunges (if at all) when I put it in gear. Hope this helps!

  • Ga426owner

Posted June 22, 2007 - 05:03 AM

#5

My 03 does not lunge at all -
this is either worn out clutch parts or free play issue.

All of these yamis are somewhat noisy....but buying a used bike is a gamble - it needs to be gone through for valve check, timing check by a knowledgeable person.....otherwise the consequences can be expensive....motor related bearing may be culprit also ......better to check than to do nothing....:thumbsup:

  • brolo747

Posted June 22, 2007 - 03:07 PM

#6

Well I figured out my clutch problem. The clutch basket has grooves in the fingers and all the friction plates had burrs that would not allow the clutch to disengage so I filed all the edges of the plates and the fingers. Now I am going to shop around for prices on a new set of f-plates and good billet basket. I am also going to do a valve adjustment once I get the basket and stuff and do a few more cleaning oil changes.:thumbsup:





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