Manual Decomp. Lever


8 replies to this topic
  • 426 NOOB

Posted September 30, 2007 - 06:21 PM

#1

I have an 02 YZ426 and I was wondering where the best place to mount the manual decomp. lever in the case of a crash. I definitley dont want to lay my bike down and land it right on the decomp lever causing the piston to hit my exhaust valve. I know, the best thing to do would be to buy 03 450 cams for manual decomp but I dont have the $ right now. Thanks

  • 642MX

Posted September 30, 2007 - 06:34 PM

#2

I have an 02 YZ426 and I was wondering where the best place to mount the manual decomp. lever in the case of a crash. I definitley dont want to lay my bike down and land it right on the decomp lever causing the piston to hit my exhaust valve. I know, the best thing to do would be to buy 03 450 cams for manual decomp but I dont have the $ right now. Thanks


There isn't a great spot for it, but the factory had them pointed up and slightly forward. I rode my bike for a long time like that and never had a problem.

Now save your money for a 450 exhaust cam. :confused:

  • 426 NOOB

Posted September 30, 2007 - 06:38 PM

#3

There isn't a great spot for it, but the factory had them pointed up and slightly forward. I rode my bike for a long time like that and never had a problem.

Now save your money for a 450 exhaust cam. :confused:


I kinda figured that would be the best spot. Thanks for the info.

  • sirthumpalot

Posted October 01, 2007 - 04:53 AM

#4

I don't think pulling the lever will open the valve enough to hit the piston?

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  • grayracer513

Posted October 01, 2007 - 07:13 AM

#5

I don't think pulling the lever will open the valve enough to hit the piston?

Nope, can't happen. It is possible that engaging the compression release at high rpm might damage the valve lifter though

  • maxx2200

Posted October 01, 2007 - 10:47 AM

#6

I have an '01 YZ426 and I purchased the GYT-R lever. It mounts under the bar rather than on top so you use your thumb. May be a little less obtrusive.
It's cool anyway, easy installation and black billet aluminum.

  • 426 NOOB

Posted October 01, 2007 - 11:45 AM

#7

Wow! Thats new info. My understanding was that the piston could hit the valve. Thanks Gray. I need to check into the thumb lever too. Thanks all.

  • C333

Posted October 01, 2007 - 11:49 AM

#8

I twisted mine around so it can be operated by my thumb. Sort of underneath and behind the bar kind of like maxx has his set up but mine's the manual stock lever. Works great and doesn't get in the way. I've crashed a few times as well. No problems yet.

  • grayracer513

Posted October 01, 2007 - 12:03 PM

#9

Wow! Thats new info. My understanding was that the piston could hit the valve. Thanks Gray. I need to check into the thumb lever too.

All that it does is prevent the right exhaust valve from closing all the way. It only holds it off the seat perhaps 3mm at most, and if the valve won't hit the piston while you crank it over, what would make it hit at a higher speed.

The GYT-R perch that was mentioned is a beautiful part. If you pair it with the matching folding clutch lever, it costs about $190. The same part from ASV is about $125 or so, although the perch isn't as cool.

You can, however, buy a camshaft for an '03-'05 YZ450 for about $110 (or less), and then you can mount your decomp lever in its proper place: on the wall with the other antiques.





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