On my 1000S I have points and 3ohm coils, one of the coils has failed, (no resistance from secondary circuit test).
As this has happened, and I am going to have to replace a coil anyway, I have decided to fit a new Dyna 111 ignition and lead set which I got at a very good price when a friend was in the USA last year; however, the Dyna can either run with 3 ohm or 5ohm coils. On contacting them for advice, their preference would be the 5ohm, as they run a lot cooler.
Now the price of the Dyna 5ohms is quite substantial and I have had a look online and have found 5ohm coils much cheaper and roughly the same size as the Marelli ones fitted to my bike. I have no doubt the Dyna ones are extremely well made and resin encapsulated and the ones I found look like standard metal oil filled coils.
The question is, could one of you electric wizards please tell me is a 5ohm coil a 5ohm coil, if you know what I mean, would they both do the same job?
If I have to get the Dyna ones I will, but if I can get ones at a more reasonable price that will do the same job all the better, I can then spend the difference on more Guzzi bits!!!
If it says 5 Ohms on it the Dtna111 will run it mine were non standard and 4 .25 and ran fine the highter the resistance the lower the running current so kinder on the control side andd nicer for the coils as they will run cooler ( not sure you would actually notice them cooler by touching)
[QUOTE=Ex smokingbiker] If it says 5 Ohms on it the Dtna111 will run it  mine were non standard and 4 .25 and ran fine  the highter the resistance the lower the running current so kinder on the control side andd nicer for the coils as they will run cooler ( not sure you would actually notice them cooler by touching)
[/QUOTE
Thank you very much!
The original Guzzi ones are rubber bodied secured by the 'B’shaped clamp with the rubber cushion above the fuses, the ones I was looking at are metal bodied, would coils with a metal body require the body itself to be earthed or would it be ok just to clamp them on using the original rubber backed clamps?
By using the original clamps they would have reduced vibration and isolated from the frame.
Or do as GTMdriver suggests bolt them straight to a good heat sink, the frame, using metal clamps to reduce heat.
I have a major problem with rubber mounted (Insulated) coils in that every coil has TWO ends on the low voltage side its 12 volt in and other usually to point power goes in one end and out other end secondry side the high voltage is just the same one end goes to HT lead to enable the High voltage side to spark we have to have the other end of that coil connected to the earth to get the return path if its rubber mounted and therefore insulated from the earth there can be no earth return path OR is it not pure ruber and contains a conducting agent in it IE carbon ?
[QUOTE=Ex smokingbiker] I have a major problem with rubber mounted (Insulated) coils in that every coil has TWO ends on the low voltage side its 12 volt in and other usually to point power goes in one end and out other end secondry side the high voltage is just the same one end goes to HT lead to enable the High voltage side to spark we have to have the other end of that coil connected to the earth to get the return path if its rubber mounted and therefore insulated from the earth there can be no earth return path OR is it not pure ruber and contains a conducting agent in it IE carbon ?
[/QUOTE]
Thanks, so if I am using a metal bodied coil use a metal clamp and bolt it directly to the frame?
Sorry if I am labouring this but I just want to get it correct.
I bought this dyna III ignition/coilset up a while back, but don’t feel I know enough to fit it. Is it easy for a non electical/electronical person to d?Sorry for butting in!
Thanks, so if I am using a metal bodied coil use a metal clamp and bolt it directly to the frame?
Sorry if I am labouring this but I just want to get it correct.[/quote]i would personally use metal clips to help with cooling
Thanks, so if I am using a metal bodied coil use a metal clamp and bolt it directly to the frame?
Sorry if I am labouring this but I just want to get it correct.[/quote]i would personally use metal clips to help with cooling [/quote]
Ok , will do, I have spare ones from my Lightning Clubman which are the correct size.
I will make up a bracket to mount them, that should give even more heat dissipation.
I also read the section in Guzziology about fitting it and where each wire goes exactly, if you want I can PM you some details.rbt15482014-08-28 18:43:44
You’ll soon know if your coils are able to cope with the Dyna system, they’ll overheat and break down internally causing backfires and eventually stop working altogether. Allow them to cool and you’ll be good to go for another few miles 'till it all starts happening again. With mine, I was able to start the bike and get the timing done without any problems but as soon a I started riding and using the revs a bit the coils went down. Dyna systems do work the coils hard so just as everyone suggests, keep 'em cool.
I think this would be because they’re ‘on’ most of the time, only being switched off for literally just a few milliseconds. As opposed to contact breaker use where they’re on and then off for approximately equal periods. Same for Rita system (long on time). If it helps mine are mounted under LH sidepanel with like steel ‘C’ clips and spacers direct to sub-frame, all metal to metal contact. Coil ‘cans’ are not connected to anything inside. HTH
]If it helps mine are mounted under LH sidepanel with like steel ‘C’ clips and spacers direct to sub-frame, all metal to metal contact. Coil 'cans’ are not connected to anything inside. HTH  [/QUOTE]
Thanks for the info.
I will go this way of attachment, using the spare brackets I have, Lucas style coil sleeves with fixing tabs that have two bolt holes for fixing to a frame or bracket.
I always thought that one of the red wires form the Dyna module was connected straight to one of the positive leads on a coil. The one that gets it’s supply from the kill switch. Nothing to stop you doing it that way of course.
Your thought is correct, but to get to the coil the power goes through both the ignition switch and the kill switch both which draw current, so will use the kill switch as a latch.
Similar reasoning to the people who have fitted a relay to their H/light wiring.rbt15482014-08-29 14:12:28