VMAX running rich, stage1 kit

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What is your elevation? I think I would go 150 on the main and try 3rd clip on the needle. You should be able to get it where it doesn't stumble and pull great without a 1/2 step shim. From my experience if it hesitated or stumbles midrange it is a lean needle condition. The stage 7 needles are very thin and a main jet change will affect what your needle setting should be. As a rule tune from the top down( main jet) and then select needle position. I would be surprised if a 150 main is not a better choice.


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Black Hills can be as high as 7000ft at the top.Average cities about a mile high.
147.5 on the main to start. 2nd clip or 1/2 step washer so 2 1/2 from blunt end.
Stumble would be a rich term and hesitated would be a lean term.
You will want to be below the normal jetting at that altitude.
 
You guys are spot on with the elevation. I live at 3500, my touring will probably be more up than down but I could still end up at sea level once or twice this year. In reading others setups I had also wondered of the 150 and a leaner needle setting would be more appropriate, but my elevation is a little higher than most of the other setups that indicated an elevation.

I'm already on that 3rd clip and that stumble is there, very slight and only with WOT from 2500rpm, roll-ons are smooth and seamless still. Maybe I should pop the 150s in to see if I see a notable difference in top end and leave the needles on the 3rd clip, just for comparison. Or if I read correctly going to the 4th clip does the same sort of thing and if that makes it pull harder at the top I should go up to the 150s then.

I did notice how thin the stage 7 needles are compared to the 1s.
 
You guys are spot on with the elevation. I live at 3500, my touring will probably be more up than down but I could still end up at sea level once or twice this year. In reading others setups I had also wondered of the 150 and a leaner needle setting would be more appropriate, but my elevation is a little higher than most of the other setups that indicated an elevation.

I'm already on that 3rd clip and that stumble is there, very slight and only with WOT from 2500rpm, roll-ons are smooth and seamless still. Maybe I should pop the 150s in to see if I see a notable difference in top end and leave the needles on the 3rd clip, just for comparison. Or if I read correctly going to the 4th clip does the same sort of thing and if that makes it pull harder at the top I should go up to the 150s then.

I did notice how thin the stage 7 needles are compared to the 1s.

Yep, if you have to go the 4th clip, go up 1 jet size.
 
I'm going to go outside and play with clips if I can shake this HA, I'll go to the 4th and see what happens, it's to nice outside not to try a few things.
 
Ok, I changed nothing but moved the needles to the 4th clip and buttoned her back up. The test ride shows it still runs well for normal riding, maybe a touch softer off idle and maybe into midrange, but I didnt touch the AF screws or even sync it up, idle and off idle still quite good so I left it alone for the sake of testing mid/top power. I noticed two changes...

1. The 2500/5th gear WOT test gave me more stumble around 4k a couple times, and a couple times it was like before, but was a touch slower to rev past 4k on said test. Again roll-ons still solid. So richening up the needles did no favors for mid-range power.

2. Once it gets around 5k-ish it starts pulling hard, through vboost and to redline it was more furious and pulled harder than on 3rd clip. I took off in 1st gear and redlined in every gear up to 4th and it was definitely harder to hang onto, so notable gains up top and upper mid. This tells me that the bike did not care for the added fuel until around vboost-o-clock and maybe a touch before.

So if I interpret the excellent wisdom put forth here I'm richer through the mid-range and top end r/t moving the needle out. Now if I tune from the top down as advised I need to keep the top end rich and lean back out the mid-range. I interpret this as it's time to replace the 147.5 mains with 150s to keep the high end rich and maybe put the needles back to the 3rd clip and work incrementally down from there until the midrange finds some happiness and a cleaner 2500rpm WOT test.

Does that sound about right to you guys?
 
Considering your elevation you might try to 2.5 on your needle clip


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I set it to 3rd clip, no shims yet but they are on the way. I'll sync them up in the morning and do another test run, get the AF set and see how she feels.

I broke the rack apart to recheck float levels again just for fun and used a different mic this time to double check. I wanted to see if any crap was getting into the carbs anyway before I start what might be a tedious tuning process. They were spotlessly clean but the levels were a touch high so I set them exactly at 1.125", glad I went in and looked again. I thought they were spot on the first time but apparently I made an error in my measurements.

For anyone reading this looking to set their floats I used this as a reference. Now they look exactly as they should according to this link.
http://www.factorypro.com/Prod_Pages/prody11.html

When this is all over I should be able to field strip these, in the dark, along side the road, in the wind, in a drunken stupor.
 
Good Job and setting the float height is definitely the first step necessary to getting your carbs dialed in correctly.
 
Ok, road test done. Pulls harder than ever in that upper mid and top end. Roll ons from any RPM get me lots of seamless usable torque BUT the 5th gear WOT @ 2500rpm test gave me considerably more breaking up and fussing through ~4k, then it cleans up and takes off, only does that on WOT test, accelerating normally its strong and swift without hesitation or stumble all throughout the rev range.

I guess I'll drop the needles to the 2nd clip, or wait for the shims and just drop the needle in half clip increments.
 
I would go ahead and try 2nd clip. That is a very quick and easy job and if it clears up then maybe try 2.5 to get precise.


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Ok, 2nd clip tried, it still fussed a bit before 5k on the 2500rpm WOT 5th gear test, not much improvement there. But it's running very well, normal roll-ons create instant acceleration, very strong and never better than now, when vboost kicks I best be hanging on if in any of the first 3 gears.

Could this WOT test fail have anything to do with AF screw settings? I know the AF adjustment was on the lean side with the occasional popping and queefing off idle today. Even on the 2nd clip it's shown only slight improvement on the breaking up before 5k on WOT. If I do the WOT 2500rpm test in 2nd gear it just launches. Would it make sense that I might have to use the first clip from the blunt end? Wouldn't that indicate to much main jet?

I know this delves into theory a bit and I hope this might be useful to others in the future.
 
I had the AF screws at 2.5 to 3, I moved them to 3 and 3.5 but haven't road tested again. There were so many HDs out today it was like being stuck behind a school bus for about 150 miles.

I figured the main jets must be ok now by the way it pulls up high, but that breaking up it does from low RPM WOT is still a thing. What, if any effect do the AF screws have on a low RPM WOT situation?

When its breaking up under low RPM WOT it feels like it did before when it was fully stage 1 and grossly rich, that same sort of stumble. There must be to much fuel getting around the needles at low/midrange when I whack the throttle...
 
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