• 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.

How much do I raise these jet needles...

  • Thread starter Thread starter Guest
  • Start date Start date
G

Guest

Guest
I'm getting ready to re-assemble the carbs from an '81 750L (16V).

Stock exhaust, with a K&N drop in air filter in the stock airbox.

I've gone up one main jet size, (112.5 to 115) because I needed to replace a broken one and I had the 115's laying around.

I want to raise the jet needles a bit as well & was wondering by how much to start? The plastic spacer measures .099". Each one of my Radio-Shack washers measures .023".

If I use 3 washers I raise the needles .030". If I use 2 washers I raise them .053".

Where should I start?? Looking for opinions...

TIA,

Mike
 
If all is stock except for the filter, and you are using the air-box lid, you probably won't have to move the needle. The bigger main should do it.
On my '81 750 with 4-1 pipe and Uni high flow foam filter in stock box, with lid on. I didn't move the needle. I went 2 up on the Main and 1 up on the Pilot jet. Runs great.
 
Personally, I would use three washers and leave the pilot jet alone. Might turn the mixture screw out to about three turns, though. :-k

.
 
Steve said:
Personally, I would use three washers and leave the pilot jet alone. Might turn the mixture screw out to about three turns, though. :-k.
Click to expand...

Thanks Steve,

Actually, I had already re-assembled the jet needle/slide assy & used three washers, then I got 2nd thoughts... apparently we think alike (is that good?)

Thanks for the 3-turn recomendation on the mix screws - I wasn't sure where to start those at. Didn't plan on touching the pilots.

I have quite a bit of work left to do, with very little free time to devote to this project, before I'm ready to start this puppy...

However, I'll post some pics when she's ready for her closeup.

Mike
 
hikermikem said:
I'm getting ready to re-assemble the carbs from an '81 750L (16V).

Stock exhaust, with a K&N drop in air filter in the stock airbox.

I've gone up one main jet size, (112.5 to 115) because I needed to replace a broken one and I had the 115's laying around.

I want to raise the jet needles a bit as well & was wondering by how much to start? The plastic spacer measures .099". Each one of my Radio-Shack washers measures .023".

If I use 3 washers I raise the needles .030". If I use 2 washers I raise them .053".

Where should I start?? Looking for opinions...

TIA,

Mike
Click to expand...

When you buy a "needle shim kit" the washers are about .020" thick. This is about equal to raising or lowering one needle clip position on carbs that have standard adjustable needles.
 
Actually, .020" is a half- a- clip adjustment, .040" is a full clip adjutment.:D
 
progas said:
Actually, .020" is a half- a- clip adjustment, .040" is a full clip adjutment.:D
Click to expand...

Yea, actually you are correct, I have exactly just that a "1/2" shim kit, I got my facts backwards. I bought the kit many years ago. Sorry for bad info..
 
Thanks for the respones guys - I did know .040" was the clip distance between each "notch" on needles that can be adjusted... thanks for verifying.

I will start with .030" (3/4 notch) and go from there - just looking to improve the mid-range response.

Happy bikin'

mike
 
You must log in or register to reply here.
Back
Top