View Full Version : i have a problem

11-11-2009, 9:39 PM
i have a 79 suzuki gs 1000. it starts up and runs fine. the problem is when i let off the throttle it pops, a shit load. i have pulled the plugs and they are perfect. whats the deal. here is a short video. <object width="425" height="344"><param name="movie" value="http://www.youtube.com/v/gEiWkR_j-0o&hl=en_US&fs=1&rel=0"></param><param name="allowFullScreen" value="true"></param><param name="allowscriptaccess" value="always"></param><embed src="http://www.youtube.com/v/gEiWkR_j-0o&hl=en_US&fs=1&rel=0" type="application/x-shockwave-flash" allowscriptaccess="always" allowfullscreen="true" width="425" height="344"></embed></object>

11-11-2009, 9:48 PM
sounds like a bad ground wire to me......... but oppinions are like assholes, everyone has one

11-11-2009, 10:29 PM
Engine might be running a little lean, even if the plugs look okay...EPA regs made these things lean from the factory. But if it was running lean enough to cause that much popping, you'd have other "lean" symptoms, like hesitation on accel.

My guess would be a hole in the exhaust or intake manifold, look for pinholes in the pipe or cracks in the rubber intake boots. When the throttle is closed but the engine is still turning heavily on decel, it'll suck in air through these gaps and make that sound.

I'm no expert either. But I do have an original GS1000 factory manual, let me know if you need scans.

11-12-2009, 9:05 AM
Hard to tell from the vid, but you probably have pod filters and open pipes on the bike, right? Your air/fuel mix screws need to be backed out at least one whole turn on each carb. I'm not at the shop yet, but I believe that the stock setting was 1 1/4 or 1 1/2 turns out, you'll probably need to go to 2 1/2 turns out and start from there. if you need to back it out more that 4 turns, you'll probably have to get bigger pilot jets.

Medusa Mike

11-12-2009, 10:15 AM
Fatten up the pilot jets and make sure it's not idling too high. It's pulling in too much air with not enough or no fuel on decellaration.

11-12-2009, 10:24 AM

11-12-2009, 10:27 AM
Sounds like fuel/air. Is the pop or backfire in the carb or the pipe? Only curious, but post the solution when you get it tuned right, please.

Or am I a damned fool, can't remember if this is fuel-injection, doubting it tho.

11-13-2009, 9:01 PM
i got new o rings for the back of the carb boots, the boots themselves are in great shape. ill mess with the air mixture a little and post the results.

11-15-2009, 4:39 PM
i asked my dad 10 times if he tightened the header bolts. he put new exhaust doughnuts in it and forgot to tighten. it still pops a little but its getting better.

11-15-2009, 10:15 PM
sounds good now. thanks for all the reply's. it helped.

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