Old Britts Power Arc and strobing the timing.
- Thread starter BGad
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As I recall, you can't strobe light time an Old Britts ignition because it's tri-spark and you get junk readings.
BTW I had that ignition unit for seven years and the bike always ran ... different. kinda unpredictable. it always got me home but was an unpredictable start. I changed to stock points and the bike works like it's supposed to. Prime, full choke, first kick start. With the old Britts ignition, the choke wasn't needed and I used a leaner main jet. Piston tops looked bad. Glad I got rid go it.
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Funny, but my experience has been just the opposite. I kick mine through slowly two times with key on, then prime and choke. First kick every time unless its really cold. Never any kick back like others have had issues with. I set TDC with a dial indicator and timed it as per instructions. Never put a strobe light on it.
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Not exactly following... can't strobe time at low idle, or can't strobe time at all?
I agree that it is hard to strobe time any ignition system at low idle, because it would be off the timing scale. I strobe time at high idle - Boyer: 5000 RPM; TriSpark: 3500 RPM.
If you get erratic readings while strobing, you may want to check your cam chain tension.
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- "Sparks three times each compression stroke. This provides a very efficient and clean running engine.
- Very easy to install. No need to run the engine up to 5000rpm to time the ignition. Just find top dead center (TDC), rotate the stainless encoder disc until the static LED timing light comes on, lock the disc down and you are done."
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Interesting - the trispark reference threw me - was unaware of this system - everyday is a school day - lol!
Can't really use a timing light on this - have to find TDC and see if the indicator LED comes on.
Looks like it is still available from Power Arc directly, which is good.
Yes, the triple spare system means it can't be strobed. Establishing TDC is the easy part. Getting that disk to stay in place while tightening the center bolt is the booger. Best of luck friend!
Darn spell check. Triple SPARK system
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Got it - I could definitely see that being an issue...
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Good bad or indifferent things Jim? Curious because I've never had issues with mine but my engine is in a pretty mild state of tune.
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My experience has been they work OK on a mild tuned low compression engine as long as the cam bushings are tight. Nothing gained and nothing lost, but they do have an increased tendency to kick back when starting.
On race tuned engines I have not had good results. The Power Arc's two short duration sparks followed by one long duration spark have not given me as good a result as one long duration spark at the right time.
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Thank you Jim. I had issues with kickback on mine till I figured out the drill. Turn the key on and push it past TDC at least once then choke and prime. Never had an issue since. Once hot it never kicks back.
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