Re: same old jetting questions :(

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That is where I am now.
I tried to contact Jon, but as when I was trying to order, he will not respond to email or phone. He has number one the worst customer service of anyone I have ever met. Just having to deal with him is reason enough to buy from UFO.
I am going to try to go to Topeka next week with Sean and we will find out where I am at.
 
Just a quick note.
After dynoing today, I was infact lean with the smaller jets and now am back to the 160's ( probably need about a 155 ) Raised the clips two positions and adjusted the cables on both banks to be equal.

Only made 121.3 HP with 81 torque. pretty pathetic for the cost of carbs.
 
im a little lost at this. reading i guess isnt enough. i have a 4-1 kerker on mine has great sound and no hesitaion at any rpm. in fact wheel starts to pull at 8k. the plugs are burning perfect so says mechanics.
i was told it has a stage 1. is that enough for filters to. i bought 4 cones and 1 for the smaller hose in the back. i threw them on and it seems to sound louder and deeper, also has a great v8 sonding 4bbl sound coming from the airbox cover. Did i mess anything up or will my pipes start blueing after some miles get put on it?
 
usually you have to put air correctors in to allow so much air to be used. are you feeling any lean conditions?
 
i took it out and it wasnt to bad seem to be better top end. had a few spots on low end. but i may just take them of before i ruin my new plugs and blue the exhaust.
 
How do you perform step #2 in first post? Start the bike cold with choke and then use throttle to get rpms while closing choke circuit? Or do you not use the choke at all?
 
Use choke as needed to get bike started. For me, 1-2 minutes. Then, once temp is as #2 says no choke.
 
Mark, I just put some kerker 4-1s on and haven't messed with the carbs yet. I can start it without choke when cold so I assume it is rich. Do I just need to back the a/f screws out a bit?
 
Yeah, I would readjust all of them. Let bike warm up first then turn each one all the way in and back out slowly. Make sure idle thumb screw is set to 1K rpms. I would check sync at same time since idle mixture screw adjustment affects sync.
 
Ok cool, I'll give it a shot. I need to sync anyway since i just put on some non leaky carb joints. Thanks Mark!
 
I just bought another 85 max. Going through all the carbs live in henderson nv (las vegas) 2030 feet above sea level what would be the calculations for (10% ethynol) 91 octane !!!!!!
 

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I have a bad situation. I installed Jon Cornell's 4-2-1 dragstar yesterday and put in a Dynojet stage 1. It ran like crap yesterday when I would WOT it from a cruise, when I went to start it this morning, the fuel pump started running and kept running for quite awhile. I started it cold, rev'ed it up without hesitation but then fuel started dumping out of the exhaust connections. Is this from the main being too large? One of my fuel mixture screws are stripped out completely and only backed out about a 1/4 turn.
 
Need a little more info on your runs like crap description. You may need to shim the needles.

Fuel pump running forever and gas coming out the exhaust sounds like you have an issue with the floats or the float needle/seat.
 
Sorry, guess I could have been a little more descriptive. It hesitates and stumbles for a bit before picking up speed at around 5k rpm after cruising for awhile. I tried the 4k WOT test in 4th gear and there is a slight hesitation just before it launches. So I am assuming the needle needs adjusted up to lean it out a bit. I've been reading threads off an on all morning and I am betting I will need to get the mixture screw fixed before I can really diagnose the issue. I tried adjusting the other 3 carbs a few minutes ago but now I learned one cylinder isn't responding to the mixture screw. I'm about to go check my needles and make sure I have them all seated correctly and I didn't leave out a spring or something!
 
hello I am new to this so I am not sure this is the right thread but here goes....I have a 98 vmax with a kerker 4-1 stage1 factory jet kit but wanted to know has anyone ever jetted the carbs to run with the Y removed from the airbox seems to me it would flow much more air without the obsruction of the Y.thanks any help appreciated
 
Just finished putting in muscle jet kit. What a pain in the ass. Old breather hose was 25 years old and had to be replaced.
Also changed all screws to Allen head. Oil change, new plugs.

So issues is popping in exhaust, is this a sign it's too rich or too lean? Air fuel are 3 turns out, mains are 157.5, needles on 4th clip. I did sync, seems to run well haven't taken it out for road test yet. Thinking sync was good, not too excited about the Motion Pro gauges...
 
Popping all the time....or on deceleration?

EDIT....well with you not taking it on the road yet....it has to be all of the time. So....another question.....did you drill the slides, or go with the stage 7 springs? Right off the bat I would say, just slightly rich. I dont know your elevation....but most people tend to make best HP using 150's-thru 155's with most people 150's or 152's....with the needle on the 2nd clip from the blunt end.
 
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