As the title suggests I have a problem with my 1996 600 SS. It only seems to happen under load between 4,000 and 5,000 rpm, it feels as if the engine is giving a little cough. It is starting OK, is fine pottering along through town and over 5,000 rpm pulls smoothly up to 8,000 with out any problems. I thought it was the heat, but it still did it this morning when it was much cooler weather, I know they are renowned to be a bit wheezy and to sufffer a bit from piston slap, but this seems not quite right
I wouldn't have thought running it on Super instead of ordinary unleaded will make any difference..........It doesn't on mine, anyway. Make sure the tank breather pipes are clear (especially the short stub that goes into the tank) and that the breather valve is on the right way round......little arrow points forward away from the tank)..... If you don't chuck the bike around or brake very hard, try leaving the breather valve out as a test........(petrol will p*ss out of the tank breather stub if you brake hard particularly with a full tank). Failing that, then could be filter issues......and after that, carb settings. AL
The breather is clear because last time it was on a paddock stand with a full tank of petrol fuel pissed out the pipe under the bike. I have a spare fuel filter, I'll try fitting it seeing what happens
After a sustained period of 80mph with the throttle kept still, will sometimes 'cough' as you say, when I give it a big handful........and it is more noticable going downhill......... No idea what causes it......it runs well and doesn't do it if the throttle is opened quickly rather than whacked open. There isn't anything else I can replace in the carbs.......... I suppose it might be filter.........but if I have to get in that tank to replace it, then the 'kin pump and filter are getting located outside the tank. AL
so many things possible so working your way through all suggestions is the best route. What plugs are you using and do you know if you have a Dynojet carb kit fitted? Could be under or over fuelling as a result of non std jetting. if bike will tolerate running with choke on - try it for a short period after you have fully warmed it up and take it through the troublesome rev range just to see if it behaves differently (and let us know).
Thanks Chris and Al Away on hols for a week I will try your choke idea and will tackle changing the fuel filter when I get back. Will keep you posted
I tried the idea of the choke at 80mph but the engine almost died on me.....talk about '8 stroking'........ I think a lot of little niggly things occur when a bike has been Dynojetted, airbox played with, zorsts played with / changed; but the bike has not been on the dyno. Dynojet provide basic destructions on how to install a DJ kit, assuming that all the bikes have the same amount of airbox cut away, same exhausts fitted etc......... ......my cans for example have nothing in them in the way of baffles and I can see straight through each end; my airbox lid just has the trumpets removed........ AL
Yep. The methodical way would be no filter, then remove trumpets, then whole lid..... recently had a similar problem on a 900 that was running all stock. Pulled the lot away and it cleared instantly, fuelled ok and found a decent chunk of hp. Seemed to be rich and the hesitation came in around where the ignition hit full advance... worth a try. It's very apparent if it works.
