Hello everybody excuse me for notting spitting through the forum but here is my question and i hope you will help me. 750SS 1991 On the front cilinder the timmelamp flikkers in high frequence and doens't stop while doing it. stand up cilinder (firts cil) frequence is half of the front cilinder and quits sometimes blinking. You hear the engine falls back to one cilinder for a flash. The engine also wants to spit back in the carburator sometimes. Cold en warm. Carburators revision new pickups and wiring new spark plugs Camshaft timing 20 degrees before dead center. Ignition 4 degrees ( on bracket) before dead center. brought to original, no result. Kokusan boxes changed between cilinders, problems stays on the first (stand up) cilinder. Any one an idea what i can check. Roy
Many options here, can you get hold of a compression tester? Have you checked valve clearance on cylinder that drops off?
Thank you Chris and Borgo for you’re quick reply. The compression is 11 bar on both cilinders. I replaced the coils for dyna’s 3 ohm. I will check the coils tomorrow morning. What I don’t understand is the frequency difference. It can be a coil? Is it that a coil works or it is dead? I thought there was nothing in between?
have you tried a different spark plug lead on front cylinder? You probably know but if you have the early grey coils then lead is non-detachable - i.e. swap would require a new coil and lead assy or a swap to later coils. Are spark plugs acceptable colour? Can you ride the bike or is the drop-out too bad? New fuel? Have you a Dynojet kit fitted to carburretors/do you have a cut-down air filter lid?
The spark plugs lead (spark plug wires you mean?) are new. It are green dyna coils Spark plugs are more black than brown. Pilot screw 3 turns out. Screw is on engine side. I can ride bike. The problem is noticeably with 1.500 t/m Fuel good be at age. I don’t have a dynajet, carbs are standaard. Needle dropped one click. Airfilter is standaard with the noses?
Reminder problem stays at the first ( stand up) cilinder. Tomorrow I will switch the coils front to back. Put new fuel in.
https://share.icloud.com/photos/0115EBa7XKd1QYcQ0QZtCKvqw if I switch the R/W with the Y/B the bike won’t run
That's not what I meant. For the horizontal cylinder swap the black and yellow wires round or the red and white, whichever pair is for the horizontal cylinder.
Allright. So I think that I understood you and that is switch the wires in the connector which is placed on the kokusan. I will.
His may not be the cause but is worth ruling out as some replacement pick ups came with the wrong polarity.
It’s a dragon this bike. First I let the bike run on one cilinder at the time, thus I didn’t connect the other kokusan when I let one cilinder run. The bike runs quit properly on one cilinder. I reconnected the connectors on the kokusan and it seems that the frequency of the timinglight is the same on both cilinders!? But the light stops sometimes, so it flickers not constantly, on the stand up cilinder! I don’t get any result in this. I will try now; Cwap the pick up wires, See if I have another coil or swap them.
when you say "pickups" do you mean the two units inside the crankcase? If so, did you fit these and were you happy that the connectors were done well and carefully insulated? Hopefully you can at least say that it's one cylinder that's not running correctly. Next step is to decide if it's caused by ignition or fuel.
Change the PU wires, no result. The bike runs very bad. Ik didn’t know that that would give a big difference in running. So the wires are ruled out. As you said just for checking. I swapped the coils no result either. It looked that it became worse. The problem stays at the fiets ( stand up) cilinder. https://share.icloud.com/photos/014KiEE2IavK9xGUcf4rs-UUw The right plug is the first cilinder. Unthinkable it’s normal with the misfire.
Yes it are the PU behind the crankcase and I connected the wiring happy. I welded the wiring and isolated them with the proper parts. It stays constantly at the first cilinder were the timinglight stotters. The blinking frequency is not constant.
