Tried separate leads from cdi , ran well till hot ( op temp ) then slowly need more and more throttle to keep it running , at worst throttle is pinned and its running @ 1500 RPM using the timing light the spark seems to be erratic , all coils test ok by ohms , will take them to work and run on a coil driver and see if they drop off
It's a vacuum operated petcock, which could account for the pulsing. The vacuum action opens and closes a valve, but to my understanding it is still gravity fed, rather than pumped. Switching to prime on my bike helped diagnose a shitty tap, maybe give that a try? (Opening the fuel lid helps also). Is it stuttery and inconsistent or just sluggish? I figure an unreliable spark would result in jumpy/stuttery running, while faulty spark timing would be sluggish.
I use a cheap inline fuel filter from supercheap which is also clear. I notice the fuel does pulsate into the filter rather than a smooth flow - I think that's normal. Try remove the fuel line and switch it to the prime position. Fuel should come out if there is enough in the tank. I've started leaving my tap in the reserve position and filling up every 200kms. Shaking the bike from side to side also helps gauge the fuel level
Hi all , Had rather a large session on the bike last night , It starts well at about the time the temp gauge reaches half point it starts to idle slower and slower till it is full throttle to maintain an idle . I tried a cdi , coils and pick ups when it was faulting , nothing changed it , it achieves 20 degrees advance when faulting . Spraying engine start at the manifold boots doesnt change it , nor does substituting the fuel tank for a test can . Have substituted loom for coil trigger wires , and pick up to cdi loom , the power supply and earth to the cdi , both have the expected voltages , and there is battery voltage at the coils almost at the buggared if I know stage , my reasoning is that if its an electrical component breaking down and my spare ones are the same replacing them with a cool one should stop the problem for a bit Tonight the carbs are coming apart for a check , if I dont find anything , the loom is coming off the donor bike . The zp has several more plugs to give resistance , Be happy when I find it
Could be valve clearances changing with heat. Fine when cold, not fine when hot. Experienced a similar thing with @Grasshopper's FZR. Won't hold idle, full revs to keep the engine alive. Tried starting again when cold, no heat from cylinder 3... intake valves clearances out of spec, one too tight, one too loose. All the other valves on all cylinders were too tight/borderline out of spec.
Just read something suggesting a bad coil can be affected by heat; might be worth comparing results of timing light from each coil (eg compare cyl 1 and 3, see if they are both producing intermittent spark once hot). That way you can isolate a dud coil. Other option would be ohm reading on coils when hot, but wouldn't recommend. Also i assume you changed the plugs?
Although, if the spark is bad, I would have thought that opening the throttle would make it worse not better... I dunno man!
Hmm... have you done a compression test? Forgive me if you mentioned it.... just taking a stab. I just have this feeling that heat in the area of some engine seals/gaskets (if bad) may cause you compression problems... Do it when the engine is warm and see where you're at...
Checked tappets all good , placed nakeds loom ontop , vast improvement . For no apparent reason the plug for the run , start switch is not in the headlight bucket , its under the tank just behind the steering head , and has a clip together rubber cover thing which catches water and causes green gunge on the plug , cleaned it up and we have a much happier bandit , Goes well , tends to flood and loose a cylinder if idled too long think a float adjust will sort this Happy Days
I think I can grave dig my own thread?! My bike has passed blue slip, is now registered and actually runs pretty damn well! Recent work: -carb kit from litetek which seems to have made a significant difference! -Tuning (some whoooole other sh*t, more below) -speedo cable replaced (it broke on maiden voyage) After fixing spark (and sorting out temp sensor, brakes, thermostat) i found that it was hard to start and would hesitate around 6-7000rpm when reving. Carb clean and an inline fuel filter sorted out the hesitation. Then, revs would hang, idle would wander and still hard starting problems. Carb seals stopped the wandering idle and reduced the rev hang. Finally, several goes at adjusting idle and pilots eventually worked out. after this, took an average of the pilot jets and made then all even which resulted in me being stranded at a petrol station with a hot bike refusing to start! Took it home, readjusted pilots to smoothest fastest idle and fingers crossed it runs fine now. (Hot start issue seems to be gone, bike starts quite reliably) Other notes, bunnings sells a $32 kinchrome hex bit set for anyone who is struggling to find a 12mm allen key for the front wheel! Big thanks to everyone on the forum who helped me out with this! Sent from my SM-G900I using Tapatalk
"readjusted pilots to smoothest fastest idle . . ." Good work! That is the way to do it. Consider the 'n' turns out as just a starting point and then do it by ear with a warm engine. When summer comes you may need to reset them a little. cheers Blair