Carbs giving me grief

[Anonymous]

I have a 83 750 with a 4-1 pipe andK&N pod filters the problem is that if the bike sits over night it starts up fime but when given gas it boggs out and sputters and backfires(even after warming up for a while) :x . If you mess with the air screw on top of the carbs for a few minutes (always going back to just about where you started) the bike runs great. I just took it out for a run and the plugs are a light brown color so I think the mixture is fine and the sync is good also the spark is good blue and strong so now I am puzzled 8O .
any help would be a great help
Thanks
Mark

[Anonymous]

Intake leak. Here:

http://www.cycleorings.com/intake.html

That's the main cause for mysterious changes in carb performance. If you're not sure when the intake boot O-rings were last changed, you need new ones.

[Anonymous]

thanks I took the intakes of an low and behold little brittle rubber doughnuts no cracks but somebody some time ago tried to silicone them and it must of finally gave way to father time

[Anonymous]

Well I put the new orings in and they didn't help. It is still doing the same thing. so any more suggestions before I go spend a *@%^$*@%^$*@%^$*@%^$ load of money at the shop on this thing

[Anonymous]

If somebody could help me out with this it would be great. I am geting tired of having to mess with the F/A screws for 10 minutes before I can ride my bike. The carbs have been jetted years ago so that is not the problem.

thanks

[gsbill]

Generally, if you give gas and it bogs...not enough fuel...too much air.Can you slowly rev the bike and gain rpm? Check fuel lines, filters, screens, yuck in the tank etc. Sticky float?

[Anonymous]

Do you suppose that just letting the bike run for 10 minutes would have the same effect as fiddling with the carbs for 10 minutes?

It's pretty peculiar that a bike with dried intake O-rings doesn't run differently after they've been replaced. Usually the difference is pretty dramatic. In any event, you're still running too lean.

That said... can you survive just running the thing on partial choke until it's fully warmed? At this point, you're heading into the area of toying with jetting (provided the carbs are perfectly clean).

I've never seen a bike with pods that ran right. They'll run OK under some conditions and pull good and hard at particular rpm's, but there are tradeoffs that, in my opinion, aren't worth it.

What I would do is start looking for a good used stock airbox, but that's just one opinion.

[SqDancerLynn1]

Problem is WAS it jetted properly to begin with. Maybe they gave up on it before. You can't beat the stock air box

[gsbill]

Before I raced my bike, it had K&N's and it ran fine, but not with the stock carbs. That setup had flatslide 38's on it..You had to spend the time jetting and tuning..I cant tell ya how many times I had my carbs off.

Short cut...Get to a dyno shop with a sniffer and you will nail your jetting every time, right on the money...Basically, for all around street, you can put a better element in the stock air box and more than likely never have to mess with it and have plenty of power. Those stock CV carbs are pretty darn good. When you try for more power, it comes in combinations of improvements, one always affects something else, leaving you to chase the balance..Personal choice.