Page 1 of 1

Sucking....

Posted: Mon May 19, 2014 11:35 pm
by rgvsp
and not the fun kind.

My 76 is sucking some unwanted air from somewhere after my winter transformation into an SP. Over the winter an SP cam went in, SP carb inlets on and the SP carbs went on. All new o rings went into the carbs, including choke. Carbs were completely broken down and cleaned.

She is holding at about 4000 rpm and the plugs are getting a white tone to them. The warmer the engine gets the worse the problem seems to get.

I've been spraying WD40 all over to try and find the leak and can't get a response. I've sprayed the head gasket, inlets, all over carbs with no rise in revs.

Any ideas on what I might have goofed up? Maybe somehow messed up o rings in pilot aircrew?

Re: Sucking....

Posted: Tue May 20, 2014 6:48 am
by tigerclaw
Excuse the obvious comment but sometimes we overlook the obvious. Idle speed screw. Cables to tight or choke setup wrong?

Re: Sucking....

Posted: Tue May 20, 2014 7:25 am
by dobbslc
O rings on the carb tops next to the diaphragm?

Re: Sucking....

Posted: Tue May 20, 2014 2:03 pm
by rgvsp
Tigerclaw,
No worries, I'm open to all ideas at this point. I've checked the throttle cable and idle screw.

Dobbs,
Those are brand new but if I can't figure this out soon I'm just going to replace all orings again.

Re: Sucking....

Posted: Wed Jun 04, 2014 3:50 pm
by rgvsp
I haven't gotten to test it out yet but I think my issue was the seals around the the throttle shaft going through the carbs. By the way, if you have an SP and order them, you need 7. Litek gives you six and even the SP manual lists 6.

Re: Sucking....

Posted: Wed Jun 04, 2014 4:26 pm
by willandrip
Tell Blair that; he will make a note of it, so as not to inconvenience others. :whistle:

Re: Sucking....

Posted: Tue Jun 10, 2014 10:24 pm
by rgvsp
Unfortunately I'm still having issues. I've replaced the throttle shaft seals and when I fired her up the problem actually seemed worse. I sprayed starter fluid between the carbs and it reved to high hell. Is there a trick I'm missing when putting the bank of carbs back together?

Re: Sucking....

Posted: Sat Jun 28, 2014 10:01 am
by glimmer
did you find a solution?
i'm guessing you've read Tony sleeps article "the great carb saga"
http://tonysleep.co.uk/info/great-gsxr4 ... ettor-saga

Re: Sucking....

Posted: Sat Jun 28, 2014 12:13 pm
by rgvsp
Oh yeah, I read that before I even bought the bike. Sadly I haven't solved my problem. Every time I think I've found something I put them back on and same issue. It is sucking unwanted air in from somewhere. I'm still plugging away trying to find it. My main problem is lack of time to work on it!