• 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.

GS850 Backfiring

  • Thread starter Thread starter Chris Finlay
  • Start date Start date
C

Chris Finlay

Guest
Hi All.

I have a 1979 GS850 and it backfires through the left exhaust. I swopped over the coils but made no differance. It is also very hard to start from cold even with full choke. Will start with a shot of easy start. Would appreciate any help.

Regards.

Chris
 
Once it does start (with difficulty) does it backfire all the time ,or just when you let off on throttle? Have you checked your exhaust manifold to make sure you don't have a leak?
Hard starting could be many things-let's start with....have you checked your valve clearances ?
 
Thanks for the reply. It backfires all the time on tick over. I replaced the exhausts with new gaskets. I have done nothing with the engine. I also rebuilt the Carbs.
 
Sounds like this is new-to-you bike??? best to figure that maintenance is way overdue. You must check valve clearance and while you have cam cover off. it's also easy to check cam to crank timing (maybe this is ok but you need to be sure).Once you know this is good, you can move on to other issues. Have you seen bwringers common issues in this link?

http://members.dslextreme.com/users/bikecliff/images/GSR_Greeting.html

rebuild carbs means- clean them and new o-ring stuff ? or aftermarket "repair" kits?
 
Chris Finlay said:
I also rebuilt the Carbs.
Click to expand...
As Tom asked, we need you to elaborate on this. :-k

Did you do the full "strip and dip" method, which includes replacing all the o-rings with the kit from cycleorings.com, or did you simply use "rebuild kits" (which are generally a waste of money) and change a bunch of parts?

Unless you did the "strip and dip" method, you can still expect to have some problems, so get ready to do them again.

Regardless of which way you "rebuilt" the carbs, you need to properly set the adjustment screws. If your bike has stock airbox and pipes, the fuel screw (the one on the bottom) should be about 7/8 turn out, the air screw (the one one the side) should be double that, or about 1 3/4 turns. After the bike warms up, slowly adjust the air screw for best idle.

.
 
Backfiring is indicative of air leaks either on the intake side or the exhaust side. On the exhaust side its usually only noticeable on deceleration.

I would follow Steve's advice and make sure you have fresh O-rings in the carbs and on the intake boots tot he head. Also do check that your pipes have no holes and are tight to the head.

Good luck and let us know what you find.
 
Thanks for all that. I will start at sorting out air leaks and go from there. I will keep you posted.
 
Also make sure you have 12V on the coils, if not check the ign switch

Also adjust the valves !!!
 
Last edited:
You must log in or register to reply here.
Back
Top