new jetting with yz camshaft

7 replies to this topic
  • yamahasocal450

Posted November 15, 2003 - 05:51 PM


i just got my jetting spot on, but i still wouuld like the yz camshaft to get the harder hit in the midrange, if i get this would i have to rejet? thanks guys :D :)

  • blue_beast_wins

Posted November 15, 2003 - 06:42 PM


I doubt it but if you do it would only be to the pilot circut.

  • YamaMonty925

Posted November 15, 2003 - 07:27 PM


I doubt it but if you do it would only be to the pilot circut.

Did you have the flywheel lightened to YZ weight? I think that would make a much bigger difference.

  • blue_beast_wins

Posted November 15, 2003 - 09:05 PM


No, i left the flywheel as is, i am a lazy rider and i hate stalling so more weight = better hill climber

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  • Indy_WR450

Posted November 16, 2003 - 05:41 AM


YZ cam will lower your bottom end grunt and will be a little more stall prone. I had one and did not like it. WR has plenty of midrange punch when uncorked and jetted right. Now if they can only make a pipe that is quiet and performs as well as uncorked! :)

  • dubious

Posted November 22, 2003 - 08:27 AM


I had to richen the main 2 sizes and leaned the pilot 2 sizes. The stock needle did not work nearly as well as the ndjn i put in either. It ran really hot with the stock main and sputtered on bottom with the fatter stock pilot jet. :)

The YZ cam has made the most diffrence from about 5000 rpm till it hit the rev limiter, and I noticed very little loss of power from idle up.

  • yamahasocal450

Posted November 22, 2003 - 09:31 AM


thanks, it looks like ill try that when i get it, just im 2 times higher than you,around 3500 feet i think i might also shave some weight off the flywheel but i think thats gettin carried away thanks :D :)

  • dubious

Posted November 22, 2003 - 10:01 AM


If your bike is jetted spot on for your temp and elevation then the moves in jetting I gave you earlier will apply- go up on the main and down on the pilot and play with the needle, youll be really close. :D The ndjn needle made a vast improvement for midrange and helped alot to get rid of the hiccup. I put a yz pipe on mine but any aftermarket open exhaust will also be ballpark. My airbox is opened up too and contrary to what most will say it is still good in deep water, just keep it well oiled and the water will roll right of and will not get sucked in! I had mine up to the seat and it ran good.
You'll love the top end thrust of the yz cam!!Beter throttle response too.
PS theres 4 vent line coming off the carb, run 1 from each side up into the airbox. My buddy didn't do this and when he hit the water hole behind me his bike stalled cause the vent lines were all under water and prevented the float bowl from venting.
I also ran a longer crankcase vent hose up to the steering head just above the oil dipstick then back down to the cradle of the frame. No water is going to get into my engine through the crank vent line unless the bars are under water.
I'm removing my e start and in the process will lighten the flywheel cause the starter clutch is bolted to the rotor and weighs about 3 oz.
My friend will machine the rotor and I've heard you can lose another 5 oz there too.
Ride on !!! :)


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