|
|
Post by lchodgey24 on Mar 8, 2021 12:32:03 GMT 1
i need a bit of advice on where to look next, my 1983 250lc starts after a couple of kicks but runs on one pot at low revs. it always starts but dosnt run on both pot unless over 2500revs and when riding it goes well but at lights and junctions dies when setting off unless i give it plenty of revs. i have had the carbs off and jets out and cleaned all i have also changed the plug leads over and it goes to the other side (so not fuel) so changed the plug caps and plugs and no different. so im into the electric tech side now and was wandering what's best to check next.
|
|
|
|
Post by shaunthe2nd on Mar 8, 2021 12:49:52 GMT 1
I think I'd be checking the coil(s) under the tank next.
|
|
|
|
Post by earthman on Mar 8, 2021 13:12:40 GMT 1
I don't suppose that you have two of those tiny in line fuel filters fitted to this bike? Try checking the fuel flow/amount that flows out of each hose if you do. These had been fitted to my bike by a previous owner, had similar problems, got rid of them, the fuel filter in the tank is more than adequate I feel.
|
|
|
|
Post by rigga on Mar 8, 2021 14:33:14 GMT 1
If the problem changes cylinder by swapping the plug leads over, then the coil as mentioned above would be the logical next step, as it works as a wasted spark firing both at the same time, changing the caps rules those out, so its either the coil itself or the leads from the coil, try finding another coil to try.
|
|
|
|
Post by chrisg on Mar 8, 2021 14:33:47 GMT 1
Sound a bit like a pilot jet/air way blockage.
|
|
|
|
Post by lchodgey24 on Mar 8, 2021 15:03:44 GMT 1
thanks for the quick reply's, next thing to swop is the coil then.
|
|
|
|
Post by rigga on Mar 8, 2021 16:41:35 GMT 1
Sound a bit like a pilot jet/air way blockage. If it was the problem wouldn't change to the other cylinder when he swapped the leads over Ignition and coil related issue. |
|
|
|
Post by bare on Mar 8, 2021 17:08:54 GMT 1
These ignitions are from Yama's Wasted spark era.
ONE coil fires both plugs at the same time.
IF One Sparks the other ...Must... as well. It's either Both sparking or none at all.
Only spark related possibility is that the coil is degraded, putting out a substandard spark
and one cyl is too hard to ignite for air / fuel reasons.
|
|
|
|
Post by shaunthe2nd on Mar 8, 2021 20:33:30 GMT 1
It may have the original or twin banshee type coils also was my thinking. Would be my next port of call if only to eliminate it.
|
|
|
|
Post by chrisg on Mar 8, 2021 20:56:25 GMT 1
Sound a bit like a pilot jet/air way blockage. If it was the problem wouldn't change to the other cylinder when he swapped the leads over Ignition and coil related issue. Missed that 🤔 |
|
|
|
Post by rigga on Mar 8, 2021 21:08:31 GMT 1
These ignitions are from Yama's Wasted spark era. ONE coil fires both plugs at the same time. IF One Sparks the other ...Must... as well. It's either Both sparking or none at all. Only spark related possibility is that the coil is degraded, putting out a substandard spark and one cyl is too hard to ignite for air / fuel reasons. Again the fault swapped over to the other cylinder, so the spark was weak enough to not fire correctly one side, and then the same symptoms the other? Lead has high resistance on one side of the coil causing a weak spark on THAT lead. |
|
|
|
Post by reedpete on Mar 10, 2021 14:42:11 GMT 1
Carb balance or reeds by the sounds of it.
|
|
|
|
Post by beardy on Mar 10, 2021 15:15:24 GMT 1
Just putting this out there as coils and swapping leads are being mentioned. A while back I had untold misfiring issues. Tried banshee coils. Carbs repeatedly stripped and brass ball removed. Stator rewound. Swapped out cdi for a known good one. Extra earths added to engine and coil. Reed valves changed. Hair pulled out. I bit the bullet and put a Vape powerdynamo system on it and runs perfectly now.
|
|
