Starting issues

[Barry]

This Panasonic battery was installed circa late 2007 to early 2008...

Ambient air temperature:73F-23C

Bike equipped with Valeo starter motor.

Battery at rest for five days since previous 25 mile ride: 12.65 Volts resting voltage.

Normal start from cold, run for two minutes, stop engine: 12.54 Volts

Remove plug wires, crank for 10 seconds: 12.45 Volts

Wait a minute,

Plug wires still off, crank for 15 seconds: 12.39 Volts

Wait five minutes, battery recovers to 12.55 Volts

Plug wires off, crank 15 seconds: 12.39 Volts

Wait five minutes, battery recovers to 12.51 Volts

Replace plug wires, bike starts immediately, run one minute, stop engine.

Wait five minutes, battery recovers to 12.52 Volts

End of test-
 

That's a very impressive performance from the battery especially given it's age.

[iwSVPyFzWDH]

Thank you Monte, My bike has the older all electric ignition system. The only semi-conductors are on the diode board. A few seconds with the ignition on and plug wires off appears to produce no deleterious effects. After writing yesterday I rode ten miles. This morning the battery is resting at 12.79 volts.

[Barry]

I have points ignition.  I still avoid open circuiting the ignition coils although I did do it once accidentally. Hopefully no damage was done and the the reduced voltage during cranking probably helps in that respect.  The concern is that  even if  damage isn't immediately obvious it's possible some latent damage to the insulation occurs.
 
Normally the ignition coil only has to produce enough voltage to jump the spark gap but with the plugs disconnected the voltage will rise to the maximum that the coil is capable of which may break down the internal insulation on old coils. Fortunately the points coils will only produce something like 14kV which is not a particularly high voltage compared to the electronic ignition coils which are more like 20kV.

[jamestnewsonr65]

Ive now got one of the dyna coils 1.5ohms, but cant try it out yet as I wont be around the bike for a few weeks. I will let you all know how I get on and see if this resolved the problems.

[Bob_Roller]

Where did you get the DYNA coil from locally ??

[jamestnewsonr65]

I got it from a uk supplier http://www.dynatekuk.com was a bit more than some of the others posted in this thread, but I prefer the look of this over the others.

[Bob_Roller]

OUCH !! That is a bit more costly than here in the ' colonies ' !!!!

I doubt you ever have an issue with it, unless it is physically damaged .

[Barry]

Dyna coils are stupidly expensive in the UK otherwise I might have bought one.  I'm always on the look out for dual out put coils at a more reasonable price and came across these which can be imported into the UK for £44 http://www.jpcycles.com/motorcycle-ignition-coils/andrews

They seem to be aimed at the HD crowd but either version would be a suitable replacement on a points ignition. Are Andrews coils well thought of in the US ?

[Bob_Roller]

I have never heard of Andrews coils before .

[Barry]

Andrews coils seem to be available in a number of US retail outlets for HD parts. There is also another identical looking coil called Andover LLC.

I've just found a similar coil in UK HD parts outlet for £32

http://www.harleyparts.co.uk/ignition-24-c.asp

[marcmax]

In looking for a replacement coil, what are the specifics that need to be followed? 12v, 1.5 ohms, etc.?

[Barry]

A dual output 12volt coil should be approx. 1.5 ohms for an electronic ignition and approx.  3 ohms for a points ignition.

For electronic ignition the 1.5 ohms will have been chosen to limit the maximum current to a level that the ICU module can handle reliably without overheating which is presumably 8 amps.

For points ignition the 3 ohms is chosen to limit the maximum current to what the points can switch reliably which is usually said to be 4 amps.

Modern electronic ignition coils used on the last of the airheads are more like 0.5 ohms which implies 24 amps but in practice the current and dwell are limited in a sophisticated way by the ignition control module.

The reason for progressively increasing ignition coil current over the years is because spark energy is proportional to the current squared. So if all other things are equal doubling the current increases spark energy 4 fold. Actually all other things are not quite equal but you get the idea why the focus on increasing current through the ignition coil.

[marcmax]

Thanks Barry. Good information to file away for the day I am forced to replace the coil on my R65. Still running a "crack-o-matic" that hasn't cracked....yet!

[jamestnewsonr65]

After getting out to work on the bike today I trial fitted the coil and noticed that I need to fabricate a bracket for it to mount on to. I have yet to get a new battery, but thought I would see if it started anyway. I couldn't get it started, but the battery turned it over just not enough to catch and fire up. Nearly, but not quite.

Im going to order a new battery and some new HT leads too as when I took the old ones off, the right side connection was very dull and almost corroded as was the connection chamber in the old coil. (This was on the side of the crack). See pic below of the difference in lead connections.

I also noticed that the crack in the old coil had got worse and this must have been the death of it.

The dyna coil is a very neat solution as a replacement on these bikes and fits well. Seems like a solid bit of kit.

[jamestnewsonr65]

I thought buying some replacement ignition leads would be easy, seems that is a bit of a minefield also. Does anyone have any recommendations on what / where to buy from in the UK.