Adjusting A/F mixure

[dsteadman81]

I recently put a UFO 4-2 exhaust on my vmax, and it seems to run different at highway speeds (around 4.5k rpm). Hard to tell if its misfiring or backfiring. It just doesn't sound smooth. So I went to adjust the mixture on the carbs and all of the mixture screws were between 6 and 8 turns out. It felt like they were backed all the way off. So I screwed them all the way in one at a time. The two LH carbs would cause the engine to stall when turned all the way in (like it should). But when I turned the RH mixture screws in nothing changed. Right now I have them all turned 4 turns out. What could cause the RH mixture screws to not change anything?



I bought this bike used from a dealer and the plugs were already removed from the carbs.

 

[dannymax]

What sort of carb mods did you do with the pipe?

 

[dsteadman81]

nothing yet, bought sean morleys jet kit just waiting for it to get here

 

[NHVmaxpower]

I would do a shotgun to the rh carbs your screws should be not much more than 3 1/4 depending on bike.

 

[sdt354]

Sounds out of sync to me.
Steve-o

 

[dsteadman81]

I should also mention when warming up, the RH cylinders take longer to heat up. After about 5-6 min the LH cylinders were hot to the touch, and the RH cylinders were just warm.

 

[dannymax]

Like std354 said....how's the sync?

 

[jfeagins]

Stop touching hot pipes. It'll only serve to burn your fingers sooner or later.

If you've ordered parts from Sean, don't do anything yet. You'll have to have the carbs off when the parts get there. And knowing Sean, they'll get there sooner rather than later.

When you take the carbs off to install Sean's kit, clean them thoroughly while you have them apart. You'll be required to synch them upon re-installation anyway, so why fuss with anything now. After you've installed Sean's kit, cleaned the carbs thoroughly, and re-synched them, I'll bet you will think you have a whole new bike to ride.

 

[Traumahawk]

stop touching hot pipes. It'll only serve to burn your fingers sooner or later.

If you've ordered parts from sean, don't do anything yet. You'll have to have the carbs off when the parts get there. And knowing sean, they'll get there sooner rather than later.

When you take the carbs off to install sean's kit, clean them thoroughly while you have them apart. You'll be required to synch them upon re-installation anyway, so why fuss with anything now. After you've installed sean's kit, cleaned the carbs thoroughly, and re-synched them, i'll bet you will think you have a whole new bike to ride.

+1

 

[dsteadman81]

Stop touching hot pipes. It'll only serve to burn your fingers sooner or later.

Im an automotive technician by trade, not too much feeling left in these fingers LOL.


Not sure if the carbs are in sync or not. Guess its time to buy a sync tool.

Im sure once the jet kit is installed everything will be fine. I just hate waiting.

 

[dsteadman81]

So I synced the carbs today and went for a test ride. It seems to run better but it still backfires on light acceleration. Is there any other adjustments I can make? A/F screws still at 4 turns out.

 

[NHVmaxpower]

What size main jets are you running it should be rejetted w/ a full exhaust & 4 turns is way too much