• 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.

main jet size for K&N's and a racing exhaust....

  • Thread starter Thread starter Seana23
  • Start date Start date
S

Seana23

Guest
Hi all, i hope everyone is well and groovy...
I'm building my GS850's carbs and am wondering if i need to up-jet the main jets from 115's to 125's...
I've not run the bike yet to do a plug chop, as i'm building it from scratch and the carbs are pretty much the last thing still to do before pressing the starter button... Exciting!!!!
anyway, i had a GS550 for some years and upjetted for an Alpha exhaust as it ran a bit lean, But this Harris racing exhaust is pretty much straight through and its also got K&N air-filters.

Thank you all in advance.
XXXSeanaXXX
 
Being a UK lass you probably have adjustable needles in the carbs, but you still may want to hunt up a DynoJet kit. Will make life much easier.
 
Just to confirm. You're running BS32s, they are genuine K&N filters, not Emgos etc, and your Harris is a race pipe rather than a Harris road pipe (externally the same, internally different).
 
gawd, now your askin...
they be CV carbs.... they be a bit smaller than the same 1000 CV carbs...
i'll google it and get back to you (im in bed and dont want to go downstairs as its cold!)....

.....BS32SS's i think according to an old GSF thread...

They are Genuine K&N's (from 20years ago) and the ehaust is 4 original downpipes running into a gentle 45 degree bend, then into a straight through, except for an end plate, Harris racing pipe.

XXX
oh, i looked in some GS1000 CV's and the jets in there were 145.5's (not sure what this means exactly but thought i'd say anyway.)
XXX
 
Last edited:
just been lookin at Dynajet kit for gs850 and they offer 3 sets ov jets 155's, 160's and 165's...
so maybe the 145'5's from the 1000 carbs i have would be better than the 115's originally fitted...
Any thoughts???
XXXX
 
If they're at all like the carbies stateside, they'll be 32SS indeed. But the jets are not what you're going to be worried about so much as the needles. Even the adjustable "Canada spec" needles I've gotten a hold of over the years don't taper fast enough for vacuum carbs with pods. The DJ kits have special pointy pointy needles (like the rabbits teeth from the holy grail :p) you NEED those. The jets are helpful but a simple maths formula can convert DJ sizes to Mikuni easy enough.
 
A 155 Dynojet main is almost the same as a 145 Mikuni (they use a different way to calculate jet size). DJ160 is a Mikuni 150 and a DJ165 is 155 Mikuni. Worth a go with those 145s you already have (and new jets from Allens or your local boys are only ?3 each).

The DK kit will set you back ?110 -120. I would have go at using the parts supplied by Mr Mikuni.

You can try raising the needles - try the bottom notch first and see how it goes. The pilot circuit will probably tune in on the mxture screw though Allens will have bigger pilot jets if you need them.

If you don't know about plug chops do a search on here.
 
You must log in or register to reply here.
Back
Top