I NEED tuning help....

[1quik6]

Okay I am new to the whole bike thing. New rider, owner and mechanic. I have no problems working on cars, but this bike I bought has thrown me for a loop. I bought it with out riding it, first mistake. I get it home and ride(put) around a parking lot. A friend that is pretty knowledgable about bikes rode it and it ran funny for him. We found that if you pull the throttle all the way open it would tottally bog, barely move. He thought that the carbs may be gummed up. So we pulled those apart and cleaned them all up. Which by the way they were not dirty at all. Put it back together and same problem. I changed plugs, again they were not bad, same problem. I am getting spark but may be it is weaker at high rpm. I should metion that if you roll onto the throttle it sounds all right. I am looking for some ignition specs or any advice. Like I said I am new to this and very frustrated. Please help.

Thanks
and sorry for the rambling,

Zak

[earlfor]

I think it could be helpful if we knew what make, year and model we were talking about. :-)

Earl

[Billy Ricks]

If they are non CV type carbs and they are a large bore size you can't just whack them open. You have to roll the throttle to keep fuel mixture velocity high. Whacking them open causes the mixture to slow down too much which causes your bogging.

[SqDancerLynn1]

Need more info! What type of air filter do you have????

[1quik6]

Sorry I guess in my raving I forgot the most important parts. It is an 81 gs750e. It acted like this with the stock air box on and last night with no filters on. I am going to an indivual filter set up. thanks for the replies.

Zak

[Einar J Skog]

Hi

At standard setup the engine will stall if there a no filter in the airbox.
the same with pod filters. Way to lean mixture.

If using pod filters you must have bigger jets.(Dynojet)(stage 3)
and a more open exhaust system.
If proper set up you can gain 8-10% power increase in top RPM.
With KN filter in air box and stage 1 you can gain 4-5& at lower RPMs.

I have stage 1 on ny bike.(have friends that use stage 3 and they say it is hard to set up properly.)
(In my Dynojet set there was Stage 1 and 3 in the same box.

[1quik6]

I understand that you need more fuel with more air flow you get out of open filters but it also acted this way with the stock air box on, and the previous owner said that he had the carb jetted up. Does anyone know what a size the stock jet should be. Again thanks for all the help. I just bought a Clymer manual today so hopefully I can get this figured out.

Zak