4mil stroker problem learn on WOT even with NO HIGH JET

Th
What intake manifold are you running?
Is was my next question. I'm running a protec mani that has the cross over. Will the cross over effect the carb signal. I have also been told my case porting quite large. I think I may have a carb signal problem.
 
I have tried 1 high speed check valve now. And 3 flame arrestors to hopefully get better manifold pressure. Still the same. Do people think this case porting is too large for my application.
 

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From whatbim reading now single tracks is the way to go on dual pulse line set up. Reading it dramatically changes carb signal which is what I think I am lacking with my case porting.
 
Have you tried the pilot jet?

He has tried it, and said he could get it to bog and then made adjustments to get it crisp again. But still having the issue with it not responding to high speed jet changes, he wanted to make it bog/rich and then dial back from there.
 
Yes large pilot of 145 gave me a little more low down bog. Hesitation goes. But still not right when hold full throttle. It should bog with too much fuel as I am using no high speed jet in my carb. After a lot of research I think I have found my fault. I believe I have a very weak carb signal due to my case porting but more so my inlet manifold. I'm running a protec mani with a crossover. I believe the carb signal is weekend by drawing air from two carb..it's basically bad on daul carbs with daul pulse lines so i read. This poor signal (low air velocity) is not able to draw fuel out the high speed circuit very well..hence changing the high speed jets made no difference. I will fill the cross over on mani Tuesday and test Wednesday/Thursday depending on work.
 

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yamanube

This Is The Way
Staff member
Location
Mandalor
I have been told the stock cylinder transfers are not large enough to effectively handle any more case volume than stock. Not saying that is entirely your problem but I'd think it might play a part.
 
Yes large pilot of 145 gave me a little more low down bog. Hesitation goes. But still not right when hold full throttle. It should bog with too much fuel as I am using no high speed jet in my carb. After a lot of research I think I have found my fault. I believe I have a very weak carb signal due to my case porting but more so my inlet manifold. I'm running a protec mani with a crossover. I believe the carb signal is weekend by drawing air from two carb..it's basically bad on daul carbs with daul pulse lines so i read. This poor signal (low air velocity) is not able to draw fuel out the high speed circuit very well..hence changing the high speed jets made no difference. I will fill the cross over on mani Tuesday and test Wednesday/Thursday depending on work.

Have you tried the 145 pilot with some sort of normal reasonable sized high speed jet?
 
you just cant help some people. partly because you cant understand what the licorice they are saying!
they use the wrong terms to describe something and they don't know what licorice they are talking about to begin with!
a weak carb signal means you cant just throw jets at it and have it run good. it means you have to get it just right, which means taking the carbs off a million times and trying different jets. that's why everybody calls buckshots junk=hard to tune. everybody loves novis=throw jets in there and ride.
I said put a bigger pilot in there if it hesitates off the bottom when you stab it WFO. 135 to 145 isn't a very big jump if it hesitates bad and the screw is out 3 turns.
you can get that out of the screw adj. 135 to 145 is only going to get the screw turned in about 1 turn and that aint enough.
stop worrying about what it doesn't do on WFO until its right off the bottom!
 
Been busy over the weekend guys sorry for not replying.

Anyway I can get the bottom end sorted. I can run a 135 on 1 turn with 21psi. But when moving onto high speed circuit it feels lean. So moved up jet sizes to try get a rich mixture on full throttle. the rich mixture never came no later how large I went on the jets. After reading a few post I found like you said a weak carb signal will not be able to draw out fuel out on full throttle and throwing every jet at it will make no difference because there is a weak carb signal. I believe this to be the large cross over on the protect mani as it's drawing from two carbs and that causes the a very weak signal so i have read.

People.are saying throw a bigger low speed jet in but if a 135 works well on that circuit why go higher. Going higher to a 145 low just gives me a very rich bottom end. Buts make very little to no effect on the high speed circuit. Because I believe there is not enough air speed going through the carbs to draw up fuel through the high speed circuits.
 
Couple things to keep in mind. The pilot jet continues delivery of fuel throughout the throttle opening range. A lot of riders run reverse jetting.

And The low speed adjuster is just for dialing in idle mixture.
 
People.are saying throw a bigger low speed jet in but if a 135 works well on that circuit why go higher. Going higher to a 145 low just gives me a very rich bottom end. Buts make very little to no effect on the high speed circuit. Because I believe there is not enough air speed going through the carbs to draw up fuel through the high speed circuits.

The reason people were saying to try a bigger low speed jet is because the best description we could get of your problem was that you had a hesitation when suddenly applying throttle. That is usually caused by a low speed jet that is too small, so everyone was saying to try a bigger low speed jet because that is what would usually fix the problem that you sort of described.

That's also why everyone is so baffled why you're screwing around with the high speed jet and keep asking for clarification on what your problem is because you keep talking about all kinds of stuff that would have nothing to do with a hesitation when suddenly applying throttle, but the only description you provided of the problem was a hesitation when suddenly applying throttle, but you are also being kind of vague about what the actual problem is, so nobody is really sure what's going on.

Now it sounds like you might have the hesitation thing fixed but you are trying to figure out why it doesn't run well with no high speed jet installed in the carb, or at least that's the best I can determine. I would try installing a high speed jet, but that's just me. I'm not sure if you have a high speed jet in your carb, I keep suggesting it but you won't tell me if you have tried installing a high speed jet in the carb, so it kinda sounds like you're going to modify your intake manifold rather than install a high speed jet in your carburetor.
 
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