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1978 R100/7 Boyer Bransden MkIII Electronic ignition

K

kmkahuna

Guest
Does anyone have this system installed on their bike?
I recently have pried my VISA out of my wallet and rebuilt my transmission, and sent the engine off to Dave Campbell in Santee to have the oil seals replaced, and now I can't get her to start up.
Troubleshooting the problem, I realized that the rotor had to be pulled off, and wanted to make sure that is NOT the problem before I start trying anything else...Fuel, check, carbs are fine (this is my recently restored bike after 1500 miles), but it just doesn't fire up...:confused:

Here's the Boyer Bransden install guide for my model:
http://www.boyerbransden.com/pdf/KIT00086__BOX00037_.pdf


Anyway, here's some pics:
First is the OT mark, with pictures of the rotor pickups at OT:
DSC_0023-8.jpg


And the LEFT side pickup:
DSC_0025-6.jpg


And the RIGHT side pickup:
DSC_0026-6.jpg



So, that's where OT is....the rotors are just about to get there.... and the next Yellow mark hits:
DSC_0032-6.jpg


Here is the LEFT side pickup at the yellow mark (just past OT):
DSC_0038-6.jpg


And the RIGHT side pickup:
DSC_0039-6.jpg


Lastly: For any of you who have these electronic ignitions: The positive side has the Red/Yellow, and the Green wires:
DSC_0040-5.jpg


The coils are connected + to - in the middle with a jumper, then on my bike, the brown ground is on the frame, and I have connected the black wire to the (-) terminal on the right coil: along with my tach wire:
DSC_0041-5.jpg


Anyone see anything wrong here? The bike turns over great, but it is as if there is no spark...
 
I have a MicroDigital on mine. You state: "The bike turns over great, but it is as if there is no spark..." Have you checked to verify if you are getting a spark at the plugs (be sure to ground the plug)?:scratch If no spark, I think I would very carefully go back through the connections between the coils, box, and the pickup, (particularly any "bullet" style connectors) to be sure they are solid and that the crimps on the wires haven't loosened. I would double check the ground wire to be sure it is making a solid connection. Also double check the jumper wire between the coils, as it may not be solidly connected (which will prevent starting... don't ask how I know...).

Lastly, if the problem doesn't present itself readily, give Rocky Point Cycle a call- the owner is very knowledgeable about the Boyer Ignitions and can help you troubleshoot: 978-212-5432.
 
Something else occurred to me... if you are powering the Boyer by connecting it directly to the battery, you might double check that the included fuse holder/fuse are making good contact (and the fuse is intact) so that the system is getting power.

The fuse holder that was included with mine was kinda cheap- I used the alternate wiring option (the second diagram on your instructions) that eliminated that power wire/fuse and instead wired it to draw power from the standard ignition wiring. It's a straightforward job and eliminates an extra wire (and potential fault) going to the battery.

I'm not certain by the photo, but it looks like you've got the red power wire and the green ignition wire both connected to the coil. If I understand the instructions' diagram (the first in your instructions), the green wires do not connect to the coil unless you are eliminating the red power wire and drawing power from the standard ignition wiring. I'd carefully retrace the wiring with the diagram in hand as a precaution.

You might take a look at the Boyer troubleshooting page: http://www.boyerbransden.com/faultfinding.html.

I can't imagine that the rotor would be the problem, and seems unlikely that both magnetic pickups would fail simultaneously.
 
Last edited:
No spark

Good morning guys:
I had a cup of coffee, went out and checked all the connections, made sure they were solid, pulled the plugs, grounded them to the frame with some clamps, checked for a ground with a circuit tester and turned the bike over and no spark...
DSC_0042-5.jpg

From the pictures, I would say the timing is fine...looks like the pickups are hitting right when the yellow mark comes into view, so I think I've eliminated the pickup as the problem. Off to the trouble shooting page. At least now I know there's no spark.
 
If it was working previously, it seems likely that the problem was introduced upon reassembly. I'm grasping a bit here, but the wiring diagram for the /7 in my Clymer manual shows a connection between the starter relay and the coil (green/blue wire); perhaps it was removed during disassembly/reassembly of the engine? The connections at the starter relay have been a lurking gremlin in my bike...
 
If it was working previously, it seems likely that the problem was introduced upon reassembly. I'm grasping a bit here, but the wiring diagram for the /7 in my Clymer manual shows a connection between the starter relay and the coil (green/blue wire); perhaps it was removed during disassembly/reassembly of the engine? The connections at the starter relay have been a lurking gremlin in my bike...

Yep, that's the frustration: the only thing that was "different" was the rotor. I can't imagine that the small coils on the pickups went bad, or that the signal from the rotor isn't getting to the unit anymore, but I think I've eliminated the other issues... That green/blue wire goes right to the (+) side of the coil, and to the electronic unit. It's got power... Another odd thing: all the instructions from Boyer show two wires going to the pickups, but I only have one...always had one...
All good problems!
Thanks for your input, Jim.
 
Worked on 'em!

Decades ago, I worked on many a beemer with Boyer's installed and most were ugly. British electrics were never a promising item on most vehicles/bikes they were in. Not to rain on your parade, BUT the best one of those is found in file 13 and install the Dyna3 or equivilant. My Dyna3 in my R100/7 has always been perfect for 100s of thousands of miles now, still have it:). I don't know if Dyna3 is still around but you'd be wise to look see, save yourself tons of issues in the future. Just my opinion with too many years doing it:)...:usaRandy
 
Yep, that's the frustration: the only thing that was "different" was the rotor. I can't imagine that the small coils on the pickups went bad, or that the signal from the rotor isn't getting to the unit anymore, but I think I've eliminated the other issues... That green/blue wire goes right to the (+) side of the coil, and to the electronic unit. It's got power... Another odd thing: all the instructions from Boyer show two wires going to the pickups, but I only have one...always had one...
All good problems!
Thanks for your input, Jim.

No worries- I hope you get it sorted out quickly. Maybe try Rocky Point and see if he can give you some suggestions... another source of help might be Mikey at Martindale Motorcycle Works: http://martindalemotorcycleworks.com/A55A76/home.nsf. He recommended the Boyer to me and says he's used them for years.

So far, I really like the Boyer over all of the other setups I've had over the years (I installed it a little more than a year ago). Good luck- please post when you get it figured out. BTW- I appreciate your write-up on your EME starter awhile back- helped me make my decision on that front... I bought one to replace my worn out Bosch- so far, pretty good.
 
BTW- I appreciate your write-up on your EME starter awhile back- helped me make my decision on that front... I bought one to replace my worn out Bosch- so far, pretty good.

Thank you, Jim, appreciate it. After doing the thread on the restoration with a good 1100 pictures or so, it seems to me I can't even get on the forum here without using pictures to explain! Old habit...and a good one, it seems.
I do like the EME starter. smaller, faster, less power!
I was hoping that the wallet and the VISA would not be the solution to this new problem, but I am reminded of why I ended up here in the first place: It's because during the resto, I thought to myself... "nah, the seals up front are FINE! I don't need to replace them!"...
My biggest lesson learned during this entire evolution is: "if you're gonna go all way, go all the way". Tear that bike down to the very nut, bolt, gear, seal, and put it back together again. Huge $$ and time cost the first time around, but you won't have to tear it apart again like I've had to do after 1500 miles..
Cheers,
K
 
Lastly, if the problem doesn't present itself readily, give Rocky Point Cycle a call- the owner is very knowledgeable about the Boyer Ignitions and can help you troubleshoot: 978-212-5432.

http://www.youtube.com/watch?v=BrjC1E1TBdg
Marissa Tomei deserved that Oscar, didn't she?

For those of you who don't know the movie: "My Cousin Vinny"... allow me to say, After careful analysis yesterday....
I guess my electronic ignition is f#$'in broken...


So, Jim:
Bill Blake at Rocky Point Cycles was great; my new box and rotor is on it's way (the rotor assembly on this one when I took it off was warped and cracked).
Thanks for the tip!
 
Well, phooey- that's a drag. That said, you may net some notable improvement with the newer unit that will make it worth the investment. I was told by both Bill and Mikey that the new Boyers have a revised advance curve (more similar to that of the stock mechanical advance) that improves performance over the older Boyers. I had not used a Boyer prior to my current Microdigital unit, so I can't compare, but I like the performance on my bike as well as with the Dyna III, and way better than points (even with a Dyna Booster).

Glad you got it figured out. Here's to a trouble free installation and happy motoring!:drink

PS: My Cousin Vinny: one of the funniest movies ever! "What's a 'yute'?" haha!
 
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