Jets or floats

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jethrobolas

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Freshened up my carbs this past winter. Floats were all set significantly higher than "stock". Set them up per the sticky for setting dry float levels.

Now I'm running out of steam up high. Lowered the clips on the needles (stage 1) and I got most of my power back, but it's pulling from the needles as soon as I touch the throttle. Super rich and missing at slow cruise. Put the clips back and it's smooth throughout the range, but leaning out and costing me power wfo

SO.......


Do I order bigger mains, or put the floats back where they were? I'm leaning towards swapping brass. What do the pros suggest?


Like a dumb ass I didn't write down the jet sizes because it screamed happily and quickly to light the shift light in 5th. Now it either falls on its face (clip 3rd groove from the top) or blubbers till I wack it open, a pop, then it rips (clip 4th groove from the top).
 
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First of all.....what size are the mains? And keep in mind the vmax likes to be lean.....but the dj instructions are to set everything up super rich.

Sent from my SCH-R890 using Tapatalk
 
First of all.....what size are the mains? And keep in mind the vmax likes to be lean.....but the dj instructions are to set everything up super rich.

Sent from my SCH-R890 using Tapatalk
My best setting running stage 1 needles was 150 mk mains.....and 1st clip from the blunt end. Everything else was too rich.

Sent from my SCH-R890 using Tapatalk
 
Yeah, gotta dig em out again. Should have wrote the sizes. I almost think they were 150s. Can't recall for sure. Regardless, I must remove the carbs either route I take.

Sounds like 1 vote for swapping brass.
 
You got stock exhaust I assume. I'd chg those needles back to stock with shim if needed...stag 1 aren't the best or easiest to set up. Can be done but prob not worth it on stock bike.
 
Dale walker holeshot 4-2, pipes and stage 1 installed by po.

Just checked out the wet float level procedure and it jogged my memory. I did the wet float. I remember now (damn foliage). I still have the clear hose with the electrical tape framed window.
 
I'm running holeshot exhaust, k&n, "Y" in place, 147.5 mains, 2.5-3 turns on idle mixture screws, carb vent lines in place... everything else is stock. Bike runs like a top. I'm at 1,000 feet.
 
Did you sync the carbs before you moved any needles? If it is running good on the top end (screamed happily and quickly to light the shift)(blubbers till I wack it open, a pop, then it rips) then your mains are not the problem.
Read your spark plugs first.
You said they are gapped at 24 w/cops. White-lean Black-rich.
Mains, if you have never changed them with stage 1 kit are probably not the stock 152.5's mikuni.
Probably dj170's non mikuni's which are the same as mikuni's 160. Probably too rich for your 600ft altitude.
Dyna jet says with a aftermarket pipe stage 1 kit go to 3rd clip on the needle and use dj170 mains. If it stumbles replace the pilot air jet in the top of the carb with their dj150 which is the same as mikuni 140.

I assume you do not have any of the dyna jet or muscle kit jets left if the PO put it in?

Personally I would see what mains are in there first and do not touch the float levels because like traumahawk said they need to 17mm first.
It will be a lot of help to find out which brand jets are in there and their sizes.

Here is a jet chart for mikuni's and dyna jet.
https://www.google.com/search?q=mik...kRn9gnljM:&usg=__B_R_Zjc-r4YGXZs_j9c6hqIwNgc=
 
You can find the dynajet stage 1 directions on the web. Take those and TOSS THAT SHIT OUT THE WINDOW.

Leave the PAJ#1 and PAJ#2 alone. Change the mains to 150's....and move the needle to the first clip....all others are too rich. How do I know that....I have an innovate A/F meter, and have ridden around with it hooked up.

http://www.vmaxforum.net/showpost.php?p=371203&postcount=41

Here is a post when I had the stage 1 needles. I had it on the 2nd clip for the run....but driveability got better on the 1st clip.
 
There was 1 owner between the guy that had the work done and me, so no direct connection. I did not receive any extra jets.
I'm guessing when the shop had it on the dyno, they saw it go lean up top. Maybe they didn't have the right jets, I'm not sure. It appears the float levels were raised above spec to compensate for the lean issue. I put the floats dead nuts on when I had them on the bench. I'm sure of this now. I know I took the time to do it right. I didn't want to have to pull those carbs again for a stupid mistake like improper wet float levels.

I suppose we might as well let this thread sink until I pull the carbs and have some hard numbers. Current main sizes, verify wet float levels on the bench, that type of thing so we aren't shooting in the dark.

The main goal of this thread was to figure out if I should put the floats back higher than stock (like I bought it) or if I should leave the floats at the level specified in the sticky in this forum and make jetting changes.

In my mind the proper way would be to adjust the jetting (swapping brass), not play with the level of fuel in the bowls. It seems I am correct in that respect.

Thank you guys for the support. I will revive this thread when I have the carbs on the bench.

I've known that this bike was off a bit when I bought it. Exhaust smelled like fuel at idle, and the mixture screws did basically nothing. Hence the reason I started fooling with them in the first place.
That's another issue I will correct this winter. Paj's need swapping as well.

Can o worms...... wide open.

Dirt bikes are so much easier.

Ps. Just synchronized the carbs before my original post. Did not help my issues.
 
There was 1 owner between the guy that had the work done and me, so no direct connection. I did not receive any extra jets.
I'm guessing when the shop had it on the dyno, they saw it go lean up top. Maybe they didn't have the right jets, I'm not sure. It appears the float levels were raised above spec to compensate for the lean issue. I put the floats dead nuts on when I had them on the bench. I'm sure of this now. I know I took the time to do it right. I didn't want to have to pull those carbs again for a stupid mistake like improper wet float levels.

I suppose we might as well let this thread sink until I pull the carbs and have some hard numbers. Current main sizes, verify wet float levels on the bench, that type of thing so we aren't shooting in the dark.

The main goal of this thread was to figure out if I should put the floats back higher than stock (like I bought it) or if I should leave the floats at the level specified in the sticky in this forum and make jetting changes.

In my mind the proper way would be to adjust the jetting (swapping brass), not play with the level of fuel in the bowls. It seems I am correct in that respect.

Thank you guys for the support. I will revive this thread when I have the carbs on the bench.

I've known that this bike was off a bit when I bought it. Exhaust smelled like fuel at idle, and the mixture screws did basically nothing. Hence the reason I started fooling with them in the first place.
That's another issue I will correct this winter. Paj's need swapping as well.

Can o worms...... wide open.

Dirt bikes are so much easier.

Ps. Just synchronized the carbs before my original post. Did not help my issues.

Right on jets not floats. :clapping:
 
Ok. Took a while, but I have gotten to it. First of all..... I fucked up. On 2 fronts.

Somehow, I didn't get the floats right on a pair of carbs. Too low. Checked for level surface, then fixed that. Checked it again the following day to be sure!

One of my diaphragm springs was coil binding. Because I did NOT seat it properly in the aluminum cover.

Now with all work checked twice (dumbass), I shall install and examine results with my Dickie'sdyno.

Paj1--90
Paj2--120
Main--150

Maybe all my mixture screws will actually have a noticable effect.
 
Ok. Took a while, but I have gotten to it. First of all..... I fucked up. On 2 fronts.

Somehow, I didn't get the floats right on a pair of carbs. Too low. Checked for level surface, then fixed that. Checked it again the following day to be sure!

One of my diaphragm springs was coil binding. Because I did NOT seat it properly in the aluminum cover.

Now with all work checked twice (dumbass), I shall install and examine results with my Dickie'sdyno.

Paj1--90
Paj2--120
Main--150

Maybe all my mixture screws will actually have a noticable effect.

Ummm shouldnt PAJ#2 be 170? Is that a typo?
 
Just guessing, could one of my slides not opening completely cause the feeling of running lean up top? Kinda making sense now.

I don't mind a bit of swapping brass, but those cables are a pita to connect to the carb. If it feels happy, I will be compelled to smile
 
Ummm shouldnt PAJ#2 be 170? Is that a typo?

I have not installed them yet. I can triple check...for my own piece of mind. But yes,120. Will that cause a rich idle?
If i understand correctly, these flow air, not fuel. At idle, smaller paj2 will mean richer mixture. At idle... Which will also effect the whole throttle range to some extent.

If so, this explains the unburnt fuel smell in the exhaust at idle. My mixture screws never leaned it out, definitely never came close to stalling even bottomed out.
 
Don't take the cables off of the carbs- take them apart on the long clear and black rectangle box under your left scoop.Paj 2 is 170Yes you are rich if the Paj2 is 120
 
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