Is the auto decompress upgrade on a 426 a bad thing??

I was reading the "thumper FAQ" and found this statement:

The 2002 and 2003 YZ250F and WR250F exhaust cams are identical except for the decompression device. So for about $160, the 2001-2002 250Fs can start just as easily as a 2003 model. This isn't true for the old 426F. The 450F cam gear has a different tooth pitch, even though the tooth count is the same. The new cam will work for a while, but the chain and gear will have accelerated wear. :banghead:

Does anyone know is this had held true? I would hate to have to reinstall my old cam and decompress lever :banghead:

Some of the first guys to do this mod were worried about the supposed accelerated wear but after several thousand miles, nothing showed up and turned out to be as reliable as ever. To this day, I haven't read of a single issue with the upgrades. If I had a 426, I'd do it in a heartbeat!

Hot Cams makes one that has the correct pitch and is less than $200 (I think.) We just installed the Hot Cams version in my buddys' 01 great! :banghead:

You can get the hotcam one on ebay now (brand new according to the seller) for around $149 plus $8.50 shipping.

You can read about it at part # 4035-1E. I am seriously considering getting one for my WR400

get a 2003+ yz cam {or the hotcam}.

get a 2003+ yz cam {or the hotcam}.

I installed a 03 YZ 450 ex cam so hopefully I'm good to go :banghead:

Thanks for the input all! :banghead:

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