B-blood red
D-de black one.
D-de black one.
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Musings on Boyer Bransden electronic ignition kit.
- Thread starter Its been a long time
- Start date
No kidding, lol. I started out making brackets like that many years ago but now I have grinders and flap wheels. I make some nice stuff, if I say so myself, lol .....
OK, the answer is, the plug caps that were in doubt work just fine. Double checked the wiring, solid 12.4v at the coil and igniter. Big fat sparks at both plugs.
That's the good news.
Bad news - It doesn't fire or even try to fire either on the kick start or the electric start. (Cranks well after doing the starter drag clip fix). I have checked the ignition timing hasn't slipped, it's spot on where I set it. Given that the engine has run, but badly and that I know I had points and condenser issues, I have to say I'm a bit disappointed with the outcome.
The ignition seems to be spot on functionally.
I'm going to have to buy a compression tester I think. See what that says. After that it'll be carburettors off again. But I can't think of anything I didn't do first time round. (I've just thought of replacing the butterfly shaft seals. But they didn't prevent it starting a couple of weeks ago).
That's the good news.
Bad news - It doesn't fire or even try to fire either on the kick start or the electric start. (Cranks well after doing the starter drag clip fix). I have checked the ignition timing hasn't slipped, it's spot on where I set it. Given that the engine has run, but badly and that I know I had points and condenser issues, I have to say I'm a bit disappointed with the outcome.
The ignition seems to be spot on functionally.
I'm going to have to buy a compression tester I think. See what that says. After that it'll be carburettors off again. But I can't think of anything I didn't do first time round. (I've just thought of replacing the butterfly shaft seals. But they didn't prevent it starting a couple of weeks ago).
You can check timing with a timing light, cranking plugs out but grounded. Try a bit of carb cleaner sprayed in the intakes? That'll narrow it down if it fires.
Thanks for that. The strobe will trigger at cranking speed (it has an induction clip you out on the HT lead) ? The plugs are cable tied to the big acorn nuts on the heads, they're well grounded and the sparks are big fat ones. Voltage on the igniter is good, direct from the battery via a relay.
I have rechecked the static timing as per BB. Presumably I should see the strobe trigger at or near the retarded timing mark? BB static setting is at the full advance mark.
My vote goes to checking timing with a strobe.
Raymond, will the strobe induction pick up actually trigger off the HT lead at cranking speed? Thanks.
Nothing to lose anyway, will try in the morning.
I think so . . .
I'll know in the morning. Not sure what I'll find as the static timing is spot on per BB instructions.
I can't really understand that after maybe 11 years the bike started second kick. Running really rough and getting worse each start until it would neither start nor run any more.
As a result of that I found issues with one set of points (sticking open) and one condenser (sparking at the points). Which is why I converted to the BB to remove dodgy Chinese parts from the equation.
But now, I have lovely fat sparks apparently at the right time from the BB. But nothing, no attempt to fire. Weird really.
Tomorrow I'll try the timing light and I think I'll order a compression tester off eBay. I think I need to prove to myself whether I have low compression or not.
What charging rotor?
How is the advance rod locked to the cam? I'm thinking, looking for a slipping shaft part moving the timing.as they always say 3 things spark, fuel, compression.
How is the advance rod locked to the cam? I'm thinking, looking for a slipping shaft part moving the timing.as they always say 3 things spark, fuel, compression.
Stock rotor.
BB ignition rotor isn't locked into the camshaft at all. It relies on friction from the nut on the 8mm threaded rod to stay in time. (It's by far the worst feature of the BB system, but that's for another thread). That's exactly why the first thing I checked this afternoon was spark, then timing. Both are fine.
Right now I am going to have to get myself a compression tester because that is the one thing that is unknown.
1 spark - yes
2 fuel - yes
3 compression - ?
Meantime while I wait for the compression tester to arrive, I'll work in the suspected dodgy indicator switch.
This uses the mechanical advance? That mechanism working smoothly?
Compression enough to run well can be felt via the kick starter. Kicking down slow it should feel like a spring as piston comes up, mostly stopping progress and not just hissing through TDC.
Coming up on one cylinder reset the lever and you should get two bumps (compression strokes) on the way down.
Coming up on one cylinder reset the lever and you should get two bumps (compression strokes) on the way down.
That BB 8mm rod is just so amateur and the PCB too thin and flexible, but the system worked extremely well on my SH...
I did make up some bushings to force the 8mm rod to center better and be more secure. In the past there had been criticism about the Gill ignition coils supplied with the BB kits. BB told me they not seen an issue. My research lead me to conclude that the issue with the Gill coil on other motorcycles was due to sparkplug gaps being set too large and straining the coil i.e. greater than 0.75mm.
I did make up some bushings to force the 8mm rod to center better and be more secure. In the past there had been criticism about the Gill ignition coils supplied with the BB kits. BB told me they not seen an issue. My research lead me to conclude that the issue with the Gill coil on other motorcycles was due to sparkplug gaps being set too large and straining the coil i.e. greater than 0.75mm.
No, mechanical advance is removed. The entire advance and points system is removed. In it's place an 8mm threaded rod passes through the camshaft bore. On the right side there's a Bush to keep the 8mm rod centred. On the left there's the magnetic rotor. Timing is set statically at full advance and it relies solely on friction to keep the correct timing. Spark retard/advance is done in the blue igniter box.
(It's a dreadful design and I'll happily discuss it later once I have the bike running. For disclosure I spent over 40 years as an engineer putting right and improving other people's machinery designs).
You're describing my concern there. Just ordered a compression tester.
Thanks Paul. There's a few extremely poor design details in the BB kit and I'll definitely air my thoughts one day.That BB 8mm rod is just so amateur and the PCB too thin and flexible, but the system worked extremely well on my SH...
The BB kit I have is using a PVL coil, not Gill. As you say, the Gill coils and igniter have a poor reputation amongst Hinkley Boneville owners. (Ironically the most common issue on those bikes ignition systems is the crank position sensor. It fails, but the factory changed the air gap to 0.8mm which apparently helps the sensor life. But they do still fail). My last bike was a 2007 Bonneville T100.
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For the benefit on anyone trying to understand the assembly of the BB ignition kit on the XS650, here's a partial screenshot of their instructions. The camshaft and 8mm threaded rod assembly is shown towards the bottom.
My long distance, An interesting line: Place a 13mm socket over the nut & sharply tap the end, this will drive the right hand bearing bush home into the
camshaft before fully tightening the rotor stud.
Thanks. I've done that (pushing the bush home). Obviously there's tolerances involved, mine was an easy push fit. Didn't really need any tapping.haven't read the instructionsvote is the bolted rod slowly slipped out of position in spite of "static timing hasn't changed".
An interesting line: Place a 13mm socket over the nut & sharply tap the end, this will drive the right hand bearing bush home into the
camshaft before fully tightening the rotor stud.
There's a couple of things lead me to not suspect the timing has moved. Firstly I can see it hasn't moved, quite clearly. Secondly if the timing was somewhere near but having moved, then I'd more than likely get some kick back, mis-firing, smoke from the exhausts, spitting back through the carbs. Something.
None of that happened. That's quite odd really.
I really have to measure and verify the engine compression to satisfy myself.
