Carb tuning suggestions welcomed!

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I'm all for being a little fat to keep it alive that much longer...but not sure which condition is causing my 1/8 throttle cruising on/off stumbling...kinda aggravating...roll the throttle and it moves with a purpose...but try to cruise in the 2.5 to 3k range and it feels like a cylinder is on/off. Still no feedback if moving the clip up to the 3rd slot from 4th (blunt) will cure this...any assistance is greatly appreciated...
 
Hard to say based on your description. I would give it a shot. Won't hurt anything and only takes a few mins. I'm running mine on the 3rd clip from blunt. I'm running 152.5 mains. Works good for me.

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I have to run 162.5 in mine or it breaks up around 5-6k and wont rev past it. Tried 150s first and kept going bigger til i found one that pulled hard to redline.
 
I have to run 162.5 in mine or it breaks up around 5-6k and wont rev past it. Tried 150s first and kept going bigger til i found one that pulled hard to redline.

Well it really depends on what size needles your running.....stock, or stage 7.

With stock needles, you have to run a bigger jet, with stage 7 needles, people have had good luck with MK jets in the 150-157 range. As a general rule.
 
Thought I'd throw you all an update. Yesterday finally found some time to fidle with the bike. I moved the needle clip up one (leaner) and reset the A/F screws to 2.5 turns. That cleaned a lot of the issues up but is still stumbles a bit when rolling on the throttle easily at 2.5 - 3k RPMs. Thoughts on final tweeks? should I bump the needle down 1/2 a position (using washers from Sean's kit) or do you think I can A/F this last issue out?

Thx

Frank
 
I would bump the needle DOWN (closer to the blunt end) using the shims in Seans kit. What your doing using the shims is lowering the needle down 1/2 a clip, instead of a full clip.

With the stock springs, the needles dont start moving until about 4000 rpm. The stage 7 springs will allow the needles to move and react sooner.

The last "stumble" that I had was actually due to a too rich condition.
 
I have the shorter springs...should I throw those in or is the 1/2 clip move the best option? I appretiate the feedback Traumahawk...
 
Finally had a chance to play with it again...so I decided to go to the stage 7 springs and take out the shims.

That made all the difference in the world for me! Low end is better, no more stumble at cruise and it still gets up and goes when on the throttle...Someone mentioned the smaller (lighter) springs move faster...that sure must be the case as I believe it's allowing those taperred stage 7 needles to allow more juice to flow earlier in the mid-range.

Anyway...I'm happy with it for now...but EFI is on the horizon...
 
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