426 Auto Decompression

3 replies to this topic
  • Bambislayer

Posted June 13, 2002 - 06:46 PM


I wonder if someone like say, maybe, uh I don't know Dr. D could make us all an auto decomp for our 426s we could deal with the weight have 5 gears and save our money. come on please?

  • forthesand

Posted June 13, 2002 - 07:15 PM


It must have been a good debate at Yam regarding the 4 speed vs. 5 speed. The weight is not that big of a deal to me. The auto decompressor will save you some time if you stall it in a moto. That's important.

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  • thumper4life

Posted June 14, 2002 - 02:36 AM


how the heck would you go about makin one of those? :) wouldnt it be expensive and VERY technical?

  • sirthumpalot

Posted June 14, 2002 - 02:53 AM


I would think it wouldn't be too difficult (a weight with a spring that spins, when sitting still the spring applies the release, when spinning the weight pulls the lever out and disables the release), but I don't know how they would fit it in the stock head without some mods. You'd probably also have to modify the exhaust cam to put the spinning thingie on there (assuming that's the most convenient place to put it). Maybe I've got it wrong, but this is my guess.

Hey, better idea! An electrical model! Maybe this is easier on the WR since it's got a lighting coil already. Anyway you just need a spring to always apply the release and a solinoid hooked to the lighting coil to disable the release. When the motor starts and you get some juice, the solonoid turns the release off. Looks simple on paper, I don't know if it would really work or not..

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