Since cars can be upgraded to a more modern Coil, why not these old airheads?
Has anybody tried a different coil set up vs the old Bosch coils?
Dynatek makes a mini 3 ohm coil pack that has peaked my interest.
Aftermarket coil options?
Aftermarket coil options?
www.beemersandbits.com
'77 R100S - http://www.joshuawithers.com/r100s
'73 /5 Toaster Cafe bike http://www.joshwithers.com/slash5
'67 Bridgestone 175 Hurricane Scrambler
'66 R60/2
'72 BMW 2002
Instagram - jj_withers
'77 R100S - http://www.joshuawithers.com/r100s
'73 /5 Toaster Cafe bike http://www.joshwithers.com/slash5
'67 Bridgestone 175 Hurricane Scrambler
'66 R60/2
'72 BMW 2002
Instagram - jj_withers
Re: Aftermarket coil options?
Hi Josh,
I am running the Dyna 3 ohm coil (the green one) on my 1971 R75/5. It will work with standard points set up also. I am running it in conjunction with an Alpha Classic electronic ignition. Its working beautifully.
The advance mechanisms and bosch coils on these old girls are 40+ years old now. Im sure there are many out there performing as good as new all the same.
Cheers
Harry
I am running the Dyna 3 ohm coil (the green one) on my 1971 R75/5. It will work with standard points set up also. I am running it in conjunction with an Alpha Classic electronic ignition. Its working beautifully.
The advance mechanisms and bosch coils on these old girls are 40+ years old now. Im sure there are many out there performing as good as new all the same.
Cheers
Harry
Re: Aftermarket coil options?
If you want the dual ouput type, Dyna coils are good. One plus is that they weighs several pounds less than two 6v Bosch coils.
A 3 0hm green Dyna is the correct one for a points set up. You can go a little below 3 ohms with points but not much. I've done some current measurements with the 6 V Bosch coils which indicated they were 1.3 ohms and I've seen suggestions that they are actually 1.2 ohms which would be about right after taking into account the resistance in the wiring harness and switches. So I'd be happy to fit a coil at 2.4 ohms if it took my fancy but definitely no lower.
A 3 0hm green Dyna is the correct one for a points set up. You can go a little below 3 ohms with points but not much. I've done some current measurements with the 6 V Bosch coils which indicated they were 1.3 ohms and I've seen suggestions that they are actually 1.2 ohms which would be about right after taking into account the resistance in the wiring harness and switches. So I'd be happy to fit a coil at 2.4 ohms if it took my fancy but definitely no lower.
barry
Cheshire
England
Cheshire
England
Re: Aftermarket coil options?
If the Dyna green is a proven replacement for the 2 Bosch, I might lean in that direction.
I was originally considering something like this:
http://www.dynaonline.com/skins/product ... yna_Coils/
The Alpha Ignition is on my list too. I'm really interested to see how it compares to a Boyer or Dyna.
I was originally considering something like this:
http://www.dynaonline.com/skins/product ... yna_Coils/
The Alpha Ignition is on my list too. I'm really interested to see how it compares to a Boyer or Dyna.
www.beemersandbits.com
'77 R100S - http://www.joshuawithers.com/r100s
'73 /5 Toaster Cafe bike http://www.joshwithers.com/slash5
'67 Bridgestone 175 Hurricane Scrambler
'66 R60/2
'72 BMW 2002
Instagram - jj_withers
'77 R100S - http://www.joshuawithers.com/r100s
'73 /5 Toaster Cafe bike http://www.joshwithers.com/slash5
'67 Bridgestone 175 Hurricane Scrambler
'66 R60/2
'72 BMW 2002
Instagram - jj_withers
Re: Aftermarket coil options?
The miniature coils look like they would fit the bill but I don't know what advantage they give over the standard green coil.
BTW does anyone else find the Dynatek web site confusing ? I hate it when they pigeon hole consumers into trendy fictitious categories. I haven't the faintest idea what a metric cruiser is or why it would need a different coil and nor do I care. I just want to look at a range of coils.
If you are thinking of upgrading to electronic ignition then to get the best out of it the coils need to be matched to whatever the electronic ignition manufacturer recommends and that is usually but not always less than the 3 ohms specified for points ignition.
BTW does anyone else find the Dynatek web site confusing ? I hate it when they pigeon hole consumers into trendy fictitious categories. I haven't the faintest idea what a metric cruiser is or why it would need a different coil and nor do I care. I just want to look at a range of coils.
If you are thinking of upgrading to electronic ignition then to get the best out of it the coils need to be matched to whatever the electronic ignition manufacturer recommends and that is usually but not always less than the 3 ohms specified for points ignition.
barry
Cheshire
England
Cheshire
England
Re: Aftermarket coil options?
If you are looking for a performance boost from the ignition system you need to look at it as a system. New coils alone will be an improvement over originals, but you may not actually feel a difference in the bike unless your originals where quite knackered.
If you stay with points, or an aftermarket point replacement trigger, you must stick with coils that are have a resistance in the 3 ohm range. That high resistance limits the amount or power the coils put out. High power, dual output coils have a resistance in the 0.6 to 1 ohm range, but that much current draw will fry your points, or the black box of a standard point replacement unit in short order. You need a trigger system that can handle the high current draw of the more powerful coils.
Silent Hektik makes an excellent crank trigger system but the price is frightening. A more reasonable kit is available from Boyer http://www.boyerbransden.com/pdf/Micro_ ... System.pdf
http://www.boyerbransden.com/pdf/KIT00286.pdf
http://www.boyerbransden.com/pdf/coil7.pdf
They have systems designed for single and dual plug heads.
If you stay with points, or an aftermarket point replacement trigger, you must stick with coils that are have a resistance in the 3 ohm range. That high resistance limits the amount or power the coils put out. High power, dual output coils have a resistance in the 0.6 to 1 ohm range, but that much current draw will fry your points, or the black box of a standard point replacement unit in short order. You need a trigger system that can handle the high current draw of the more powerful coils.
Silent Hektik makes an excellent crank trigger system but the price is frightening. A more reasonable kit is available from Boyer http://www.boyerbransden.com/pdf/Micro_ ... System.pdf
http://www.boyerbransden.com/pdf/KIT00286.pdf
http://www.boyerbransden.com/pdf/coil7.pdf
They have systems designed for single and dual plug heads.
Garnet
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Re: Aftermarket coil options?
I'm going to be fitting a different gastank so the smaller, the better.barryh wrote:The miniature coils look like they would fit the bill but I don't know what advantage they give over the standard green coil.
The Boyer Bransden micro digital ignition kit including coils seems like a good way to go for this project.
www.beemersandbits.com
'77 R100S - http://www.joshuawithers.com/r100s
'73 /5 Toaster Cafe bike http://www.joshwithers.com/slash5
'67 Bridgestone 175 Hurricane Scrambler
'66 R60/2
'72 BMW 2002
Instagram - jj_withers
'77 R100S - http://www.joshuawithers.com/r100s
'73 /5 Toaster Cafe bike http://www.joshwithers.com/slash5
'67 Bridgestone 175 Hurricane Scrambler
'66 R60/2
'72 BMW 2002
Instagram - jj_withers
Re: Aftermarket coil options?
A coil is a coil.
Match the #s and any brand / option works.
Your choice.
Match the #s and any brand / option works.
Your choice.
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Re: Aftermarket coil options?
We were swapping different coils some 35 years ago. I am sure that today one has far more options.
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