Zephyr 1100 (ZRT10A) Ignition Coils - where to source?

[riders_pants]

Hello,

My bike is mis-firing, and suspect the ignition coil. Can anyone recommend where I can get a replacement(s)?

Regards

[chrisu]

usual suspects - e.g. Wemoto, ebay etc

Goggle is your friend.................

[z1bman]

some used ones on e bay

[riders_pants]

usual suspects - e.g. Wemoto, ebay etc

Goggle is your friend.................

Thanks. What's interesting is that the aftermarket coils are listed as the same part for all 4, but the original part had 4 different part numbers for each coil. Do you know why that would be? Is it just because the original parts came with pre-made leads at the right length?

[moizeau]

Probably due to the HT lead length. Have you tried pulling one of the plug caps from each cylinder. That'll narrow if down if coils.
Also what is the mis fire like, idle, mid range or flat out?

[chrisu]

usual suspects - e.g. Wemoto, ebay etc

Goggle is your friend.................

Thanks. What's interesting is that the aftermarket coils are listed as the same part for all 4, but the original part had 4 different part numbers for each coil. Do you know why that would be? Is it just because the original parts came with pre-made leads at the right length?

probably all long leads and you cut to length.........

[chrisu]

usual suspects - e.g. Wemoto, ebay etc

Goggle is your friend.................

Thanks. What's interesting is that the aftermarket coils are listed as the same part for all 4, but the original part had 4 different part numbers for each coil. Do you know why that would be? Is it just because the original parts came with pre-made leads at the right length?

probably all long leads and you cut to length.........

[riders_pants]

Probably due to the HT lead length. Have you tried pulling one of the plug caps from each cylinder. That'll narrow if down if coils.
Also what is the mis fire like, idle, mid range or flat out?

So - my original issue was cylinder 2 was not getting warm, and the bike was running on three. I took the plugs out of 2 (second from left as you sit on the bike) and they looked dirty, replaced them, and it ran better, but still mis-firing and popping.

[moizeau]

Below 2500rpm? If one cylinder is cold it's not a coil, the coils share themselves around. What RPM's does it miss, hot or cold?

[riders_pants]

Below 2500rpm? If one cylinder is cold it's not a coil, the coils share themselves around. What RPM's does it miss, hot or cold?

My theory is I think a misfire or fault on one of the plugs (from the coil) caused both the plugs to stop working correctly, meaning that cylinder went out of commission (running on three). Changing the plugs helped (and lots of smoke and unburnt fuel later), but it now pops and bangs and misfires. So, the assumption is that at least one of the coils or coil leads in faulty. I figured it would be worth changing them out ,as the leads and coils all look original, so nearly 30 years old?

Happy to be corrected if you think that I'm going down the wrong path.

Initially I even had problems with revs - like it would rev and the revs would not drop, like the carbs were hanging but that seems to have sorted itself out.

To make matters more complicated, I also changed the carbs out to a set I had reconned in case that was the issue. So, I guess it could be the swapped out carb too, but I don't think so.

[moizeau]

One coil doesn't feed one cylinder, they are shared, I'd be looking at a carbs, doing this atm on mine

[riders_pants]

One coil doesn't feed one cylinder, they are shared, I'd be looking at a carbs, doing this atm on mine

I understand that. And I have already changed the carbs to rule them out. Order of play:

Ran on three
Changed plugs
Changed carbs
Now mis-firing.

[moizeau]

What revs is this happening at? And have you got a stable idle?

[riders_pants]

What revs is this happening at? And have you got a stable idle?

Idle is pretty stable. Carbs are pretty well balanced (but can't properly balance them whilst it is running like this).

Its when you rev the bike it mis-fires. It's not consistent at one RPM or throttle position. Which makes me think it's related to the spark. Plus that start of the issue I had the bike running on three.

[moizeau]

If it's running three, it's not a coil, maybe a 12v feed issue, no ignore that, I was talking cobblers