TOPIC:

I suspect the Newtronic ignition may, like the Dyna S, have the coils energizing by default anytime the ignition is turned on. That could lead to an eventual meltdown of a coil, or more likely a dead battery, if you leave it on unattended for a long period.

Have checked the existing coils on bike (melted ones) getting 2.3ohms, the new (old )B model ones giving 4.9 ohms .. book says 4. Im hoping the .9 is nt going to make much difference . 4 ohms also suggested by Newtronic for the electronic ignition.
The problem I know have is the leads on B model are factory fixed and too short. Do I extend the HT leads with a connector ... not my preferred method or can anyone suggest a comparable set of coils like the F model with a screw cap on the secondary end that gives a reading of 4 ohms.

Has anyone tried the extension method .. good / bad results ?

adbz650 wrote: ...coils on bike (melted ones) getting 2.3ohms, ...

4 ohms... suggested by Newtronic for the electronic ignition.

That could explain the melt down during normal running. The Newtronic dwell may be too long for 2.3 ohm coils.

You can use the Emgo 4-ohm coils. They are inexpensive and have been reported as pretty good. But I think they come with plug wires attached already. You have to cut them to length and put ends on them.

You can probably alos use Dyna 5 ohm coils safely... maybe even 3-ohm coils if Newtronic says 3 ohms is ok.

In general, using coils with higher ohms is "safe" in that it won't damage anything. But they charge slower, so you want to make sure you have enough dwell... and I think the Newtronic has plenty.

The 4.9 ohm coils will work with plug wire extenders, but that can get troublesome in the long run for reliability. And the fact that they measure 4.9 could mean they are getting old beyond their service life.

This might help.
Steve

Thanks for that swest ... but Im worried about getting new wires back into it after removing the factory fitted ones. Can anyone else recommend a 4ohms set of coils with screw caps that would do the job.

I bought some later model Kaw coils on eBay. Lots of them there. They worked fine but I wanted some Dyna green coils so I finally got them. Not a great big difference but I can find new replacements easy.
If you chose to replace the wires on your old coils you can use epoxy, JB Weld or silicon to glue them back in. Just be careful not to get any on the end of the wires. Rather than spend the money on coils, I'd buy the wires, try using my old coils and if that didn't work, I'd still have the wires for my new coils.
Steve

Thanks Swest

The ones in the pic are identical to the old melted ones .... they give about 2.3 ohms of resistance. Ive managed to pick up a set of z1000 which had a reading of 3.6 ohms. Managed to get them fitted yesterday, tidyed up wiring and she roared into life on the first push of the button. Much better starting than before, only problem coils felt hot. Did nt run her for long but hoping to have a bit of a test drive tomorrow ... curiously the engine seemed to run hotter ??

If these fail I still have the new old coils of a B model .. giving 4.9 ohns but will take a bit of modifying to get them to fit. Also picked up some inline ht connectors so have a plan B. Is there anything else I should look at as to why the coils may be getting too much power ... its recording 12 volts at the terminal ?

Many Thanks

In operation, coils get turned on and off. With points, the coils are turned on for about 1/2 of the time, and off for about 1/2 of the time. That means they are able to cool down for about 50% of the time.

With the Dyna S, and possibly also the Newtronic, the coils are on about 90% of the time, and off about 10% of the time.
That means they have much more time to heat up, but just importantly, they have almost no time to cool down. So regardless of ohms, the coils will run hotter with those aftermarket ignition systems than with the original points.

With the 2.3 ohm coils, they ran hot enough to melt. But with 4 ohm coils, they should run hotter than with points, but not hot enough to melt.

Cheers loud

Got a Christmas toy run on sunday so will be able to give the bike a decent run .. in the mean time ill try and get out and give a few laps round the local area (just incase of break down ) Thanks for all the help

All seems good with coils but have read an article on getting an inline 1ohm resistor to reduce the load so will look to fit that soon. Have a christmas toy run on sunday so bike will get a bit of a blast and I can see how the new coils react under load.

Many Thanks for everyones help and suggestions