Page 1 of 2

Won't idle right after carbs o ring change

Posted: Sat Jun 23, 2012 7:24 pm
by Zemon
It's a gk76a

We just took carbs off, done the o rings, re fitted, bump started but she idles at almost 0 whilst running and dies after a 30 seconds. We adjusted screws at 1.5. It looks like an sp but the carbs don't. We are Gona try 1.8

Any other ideas

I'll pop a video up in a sec

We did take it for a run but got told off by police lol

Re: Won't idle right after carbs o ring change

Posted: Sat Jun 23, 2012 8:18 pm
by Jaicen
We did take it for a run but got told off by police lol
Awesome!

Can you get us some pics of the carbs? What year is the bike?
Will it idle with the choke on, or does that cause it to flood?

I think you've possibly pinched one or more of the main jet O-rings, which lets fuel flood the cylinders and fouls the plugs. Run it till it stops, then pull your plugs and see if they're wet, then get back to us.

Re: Won't idle right after carbs o ring change

Posted: Sat Jun 23, 2012 8:46 pm
by Zemon
We adjusted screws to 1.8 an it runs better. I think it was running Lean. It doesn't cut out now but still not right. turned it up more and it started to smooth out a little, still not right but stank of fuel from exhaust.

We did note that the screws were all at different positions when we removed carbs

Re: Won't idle right after carbs o ring change

Posted: Sat Jun 23, 2012 9:03 pm
by Zemon
It's a 1990 it has an sp body and we think it I an sp but not 100%


Choke isn't the issue I don't think

Video:http://i1172.photobucket.com/albums/r56 ... 92ed28.mp4

These are the carbs Image


Although it doesn't cut out now I changed to 1.8 turns

Re: Won't idle right after carbs o ring change

Posted: Sun Jun 24, 2012 11:52 am
by Marsbar
oh its on a car lol :/ your jetting and needle height will need to be changed, best taking it to a dyno for A/F mixture graph.

Re: Won't idle right after carbs o ring change

Posted: Sun Jun 24, 2012 12:57 pm
by Zemon
A car??? It's a gsxr 400 lol

Re: Won't idle right after carbs o ring change

Posted: Sun Jun 24, 2012 5:48 pm
by Marsbar
you posted the wrong vid then :/ but a dyno graph works wonders anyway

Re: Won't idle right after carbs o ring change

Posted: Sun Jun 24, 2012 9:23 pm
by Zemon
Doh

Here is The right one:http://i1172.photobucket.com/albums/r56 ... 373e65.mp4


Anyone know what connects here:Image

And what this connects too ( pipe running across left to right, comes from carbs but where should it go ) :
Image

Also the plugs were black an he adjusted them to a figure he found online but sounded like it was Gona go bang. Anyone know The correct gap size??

Also any ideas if it's sp or not an sp model??

Cheers

Dave

Re: Won't idle right after carbs o ring change

Posted: Mon Jun 25, 2012 12:32 am
by rgvsp
Looks like a standard GK76. Carbs look to be standard (no tps) and forks don't have the SP adjustments.

The picture of your tanks is for a drain/overflow (not sure of function) but a hose should run down to the mid pipe. There are two other hoses there as well.

The hose on the carb looks to be one of the hoses that should run back and clip onto the air box. It vents to the atmosphere, doesn't connect to anything.

Re: Won't idle right after carbs o ring change

Posted: Mon Jun 25, 2012 7:58 am
by Jaicen
I asked about the choke, because if you can start the bike without choke, your o-rings are probably leaking.
Given that the plugs are black, it's definitely running rich, so I'd be looking at the carbs again.
Have you had it running before the carb strip down?