• Required reading for all forum users!!!

    Welcome!
    Register to access the full functionality of the GSResources forum. Until you register and activate your account you will not have full forum access, nor will you be able to post or reply to messages.

    A note to new registrants...
    All new forum registrations must be activated via email before you have full access to the forum.

    A Special Note about Email accounts!
    DO NOT SIGN UP USING hotmail, outlook, gmx, sbcglobal, att, bellsouth or email.com. They delete our forum signup emails.

    A note to old forum members...
    I receive numerous requests from people who can no longer log in because their accounts were deleted. As mentioned in the forum FAQ, user accounts are deleted if you haven't logged in for the past 6 months. If you can't log in, then create a new forum account. If you don't get an error message, then check your email account for an activation message. If you get a message stating that the email address is already in use, then your account still exists so follow the instructions in the forum FAQ for resetting your password.

    Have you forgotten your password or have a new email address? Then read the forum FAQ for details on how to reset it.

    Any email requests for "can't log in anymore" problems or "lost my password" problems will be deleted. Read the forum FAQ and follow the instructions there - that's what we have one for...

  • Returning Visitors

    If you are a returning visitor who never received your confirmation email, then odds are your email provider is blockinig emails from our server. The only thing that can be done to get around this is you will have to try creating another forum account using an email address from another domain.

    If you are a returning visitor to the forum and can't log in using your old forum name and password but used to be able to then chances are your account is deleted. Purges of the databases are done regularly. You will have to create a new forum account and you should be all set.

Took my airbox cover off

trevor

trevor

Forum Guru
Past Site Supporter
I thought I would experiment with the 750 and the issues I'm having with the bogging between 2800 and 3200 rpm and at the top of rpms when up around 7500 to redline I get some sputtering too. Anyway I took the cover off the filter box and went out for a ride. I was a little surprised that the bogging was almost not there at all but what really impressed my was how hard and clean it pulled all the way to redline. Any idea what gives? Is it ok to run my bike without the cover?
Thanks,
Trevor
 
The cover makes it quieter, restricts the air flow a little bit. You must be a little rich, so a little more air works better?
 
Yeah I'm really surprised what a difference there is. Not sure if I ever had it pull so hard to redline!:D:D That's fun!!:p I forgot to mention (not sure if it matters) I have a K&N filter in it and of course the V&H 4to1 stage one dyno. Thanks for the help guys, really appreciate it.:) Oh and it's ok to have the lid off then? And tkent I have been running a bit rich I believe.
 
The lid was probably not letting the K&N flow as well as it should. Jetting problems up top are usually rich conditions. If you still have the stumble down low that's needle position. A plug chop could help tell where you need to be on the needle.
 
tkent02 said:
Spend some time tuning, get it perfect.
It will really wake it up.
Click to expand...
If what happened tonight is any indication, then it will be well worth it.:)
And Billy, I do think it is needle position too. Goody I get to take my carbs out.:p
 
trevor said:
If what happened tonight is any indication, then it will be well worth it.:)
And Billy, I do think it is needle position too. Goody I get to take my carbs out.:p
Click to expand...

The needles don't do much at wide open throttle, that's the main jet working. I bet someone put in too big main jets to compensate for the pipe/K&Ns, just took a guess at it, threw some jets in and called it good. You just made it a little less rich with the cover off. Find what size the bike came with, find out what size you have, go in between.

Pipe and K&Ns in the stock box shouldn't require a very big jet change. It's changing the intake that makes the bigger difference.
 
tkent02 said:
The needles don't do much at wide open throttle, that's the main jet working. I bet someone put in too big main jets to compensate for the pipe/K&Ns, just took a guess at it, threw some jets in and called it good. You just made it a little less rich with the cover off. Find what size the bike came with, find out what size you have, go in between.

Pipe and K&Ns in the stock box shouldn't require a very big jet change. It's changing the intake that makes the bigger difference.
Click to expand...
Yeah Kent I was referring to the bogging at 2800-3200rpm. That's right isn't it?
Thanks,
Trevor
 
With CV carbs the main jet will effect the lower circuits. CVs should be tuned from the top down, main jet first, then needles, then screws. It would be a shame to finally change main jets only to find out you had messed up something else and had to change back. You can take off an outboard float bowl, take a main jet out to see what size it is easily enough, maybe even swap all four without taking the carbs out. Most GSes you can if you are stubborn enough and have the right tiny tools.

I think it's likely someone just popped a bigger main jet in without really knowing what he was doing, if he had changed the needle position it wouldn't effect wide open at all. Since wide open was a little improved with the cover off I think he must have changed the main jets.

Find out what is in there first.
 
I have 115 main jets in my 750, that is what cleaned it up when I installed a pipe and a K&N filter. I also took into consideration the altitudes I ride at which would be between 3,500 ft and 9,000 ft. Once I get to around 6,000ft I usually have to bump up the idle a little.
 
When i had my bike dynoed, the tuner removed the lid on 3rd run, as she was running a bit rich. Still have it off ;), and i have k&n filter as well (plus bored, cams, header). Not saying that this setup is ideal re optimum performance/tuning... tkent and others covered that pretty well in above posts.
 
You must log in or register to reply here.
Back
Top