Gsxr 600 srad surging at constant throttle
 

Ive had a problem on my 1999 gsxr 600 since ive been riding it, but fairly inconsistently until recently. Over the last few days its become a bit more common, the problem is that on constant throttle between 30-40mph the bike does what i can only describe as a surge. The throttle position is constant but the bike will get in a rhythm of dropping power for half a sec or so, then getting power back again for half a sec or so. If i accelerate slightly the problem will go instantly.

Ive bought some redex on the off chance itll save me some bother but ive read before now that its not much cop.

Im thinking its a fuelling issue, something to do with the carbs... Should i look at balancing at the first step , or is there any other ideas ?!

Re: Gsxr 600 srad surging at constant throttle
 

balancing is the easiest and cheapest thing to try first providing you have gauges. My thunderbus used to do it when cruising at 80-90 on the motorway, a coil was breaking down.

Re: Gsxr 600 srad surging at constant throttle
 

Carb balance by the sounds of it. My SV does that when they drop balance

Re: Gsxr 600 srad surging at constant throttle
 

Yeah ive got a set of balancers and my dad knows how to do it so i think thats next port of call..will report back when ive done it, cheers guys

Re: Gsxr 600 srad surging at constant throttle
 

I'd suggest an intake air leak as a possibility or other sort of lean running. Or possibly some crap in the pilot circuit/low speed needles.

Re: Gsxr 600 srad surging at constant throttle
 

Ok, will invsetigate further for that if nessacery after i balance it.

Re: Gsxr 600 srad surging at constant throttle
 

Yep worth checking the balance but as YC says it sounds a bit lean. How was it in the other recent cold weather? I think the carbs have a sort of plate heater to try to prevent icing but it's crap, so the cold air (especially when moist) coming in through the scoops can overpower it. If it hasn't packed up, of course. Redex, waste of time, fix the mechanical problem or if you suspect carb heat problems then try a bit of Silkolene FST (isopropanol) or equivalent.

Re: Gsxr 600 srad surging at constant throttle
 

Been fine in the other recent cold weather but thats mostly been above 30/40 where ive had the issue

Re: Gsxr 600 srad surging at constant throttle
 

Carb icing doesn't make it surge, IME, it makes it fall on it's backside when you open the taps to overtake or go up a hill or something.

Re: Gsxr 600 srad surging at constant throttle
 

Also presumably youd only get that at sub zero temps, which it defo wasnt the last 2 times ive had it