Threw a timing chain and bent a valve

7 replies to this topic
  • LugNut

Posted June 26, 2002 - 08:29 AM


Just got the call from my local shop where I have work done.It seems my 00 426 has threw the timing chain and bent my valve.This is all new stuff to me because I bought the bike a couple of mths ago from a guy that raced it...he was pretty slow though so i figured there was'nt much abuse the bike had to have taken.At least not until I got on it...I came off a 250 and tried to ride it like a 250 it only got me through 2 races before it blew.After telling my friend this he said to go ahead and put a new piston and rings in it as well while it was open.My question much should this cost me? And is there anything else I should be looking at replacing now so it does'nt end back up in the shop sooner than later?

  • sirthumpalot

Posted June 26, 2002 - 09:13 PM


I'm sure your mechanic will do this, but be sure you find out WHY your timing chain skipped a tooth or came off or whatever happened to it. That's not normal.

  • LugNut

Posted June 26, 2002 - 09:30 PM


Oh boy I did'nt wanna hear that :)

  • sirthumpalot

Posted June 26, 2002 - 11:24 AM


If your mechanic is good then he should be able to find the cause and replace all related parts and you should be as good as new. And if you can get out with only a bent valve for damage then that's not too bad. :)

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  • bassr_#186

Posted June 26, 2002 - 11:35 AM


Your mechanic will probably know this, but I would have him make sure the timing chain automatic tension adjuster is working properly.

  • LugNut

Posted June 26, 2002 - 02:39 PM


You guys are helpful as all hell and I mean that!All this info is greatly appreciated ,I hate to go there and expose myself for the no wrenching spode that am ,(as if it werent obvious enough) but at least I can sound somewhat educated on the matter.
Thanks again and please keep em comin!

  • yamie_rider

Posted June 26, 2002 - 02:54 PM


Let us know how it goes.

  • guidster

Posted June 27, 2002 - 04:10 AM


I am sure that your mechanic will do this, but he should also look into the crank and connecting rod as well. Sometimes they get messed up when the piston slaps a valve!

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