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Jet Needle position?

B
Jan 26, 2013
79
10
8
When your on the cusp of jet needle position based on elevation, what's the tolerance for being 1/2 clip too lean for the specs?

I'm in a new area where I should be clipped at 2.5 but I can see colder temps (which I doubt I'd be riding i) or slightly lower elevation (more likely) where I would need to be at 3.0. I'm currently at 3.5 and need to clip it back down, plugs are continuously black. I hate moving needle clips more than anything and don't want to be back and forth all the time. Can I at least ride enough to get a descent set of plugs to read at 2.5 where I should be 3.0 or is that like a burn down death sentence.
 

TRIPLESWILLNEVERDIE!

Well-known member
Lifetime Membership
Feb 19, 2008
526
74
28
Northwest, MT
There should be two plastic washers or shims in there with your clip. Stock they both are located under the clip. So if the circlip is in the 3rd groove with both shims under it is considered the #3 position.
One washer equates half a clip position. You can run both washers under the clip or above the clip or one on each side of the clip to fine tune your clip position.
Make sure you have those clips in there. if not your needle will have free play and bounce up and down in the slide. fuel delivery could become inconstant causing a jetting nightmare.
 
B
Jan 26, 2013
79
10
8
There should be two plastic washers or shims in there with your clip. Stock they both are located under the clip. So if the circlip is in the 3rd groove with both shims under it is considered the #3 position.
One washer equates half a clip position. You can run both washers under the clip or above the clip or one on each side of the clip to fine tune your clip position.
Make sure you have those clips in there. if not your needle will have free play and bounce up and down in the slide. fuel delivery could become inconstant causing a jetting nightmare.

Thanks. I've adjusted them before, I just moved and am on the cusp of the range between 2.5 and 3. Trying to get some feedback on how tight the tolerance on the clip position and midrange jetting is. If I ride it at 2.5 below the minimum altitude is that an immediate burn down?
 

TRIPLESWILLNEVERDIE!

Well-known member
Lifetime Membership
Feb 19, 2008
526
74
28
Northwest, MT
I doubt it. A half needle clip position wont change much. Don't be scared, just keep an eye on the plugs and piston wash if you have a light. Avoid running the sled at 3/4 throttle for too long if it is anywhere close to running lean. That is where the piped Yamaha triples tend to get too lean in the upper midrange.
 
B
Jan 26, 2013
79
10
8
Thanks,
I don't have pipes and jetting is still rich. I looked at some plug pics I had taken and they were black. When I get to adjust them I'll set them at 2.5 and watch them. Adjusting needles is a pita and always a little risky tearing the carbs down.
 
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