850 Extreme kickback on Kick Lever From Boyer???

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Mar 1, 2007
Hello again. My buds 850 commando almost broke my ankle today. He complained that it happened to him on several occasions before he parked it a couple of years ago. When I tried to start it I got the hardest kickback fom a commando I have ever had. I thought it broke my foot. I just rebuilt the top end but the problem was there before I did a valve and ring job. It doesn't do it all the time?? Once started it ran quite well except for a spit on takeoff once in a while. I rechecked all the connections when I did the top end and made sure the boyer power wire and all wires were cleanly connected to power and grounded well. Has anyone else had this problem and are these Boyers just Crap?? It has a single mukini carb and a BOYER IGNITION that is about 12 years old. What newer ignition would you recommend for a weekend rider??? I have heard of a Pazon??? Is it better that that piece of %$#@&&& Boyer??? Please help before I break my ankle---Thanks for any replies---Mark Cigainero
Number one have you clean the kill switch or tried wiring around it? Boyer's random fire when supplied with less than 10 volts. Has the key switch been renewed? If all else fails check the trigger wires for breaks at the plate. I don't think you need a new system.
Mike, Given that this problem has been there for some time have you checked the timing with a strobe light? I have found some considerable discrepancy between static and strobe timing on a Boyer unit.
Also when your strobing are you aware that almost every Commando has it's gage for this out of phase by about 3 degrees? They must be checked with a degree wheel and than use corrected numbers. I scribe the corrected number inside the timing cover.
I've posted this before, but will repeat it. If you have not checked the timing marks on the primary chaincase cover with a degree wheel, you MUST do so. They have been found to be as much as 12 degrees off. So, before you do anything else, check this, then do a strobe check and compensate accordingly.

My machines with Boyers work just fine and have for over 15 years.
Regardless of timing, if the Boyer is seeing low volts then it will kick back like this. Are you using the same battery as when the problems first arose several years ago ? A couple of years unused will not have helped it either.

The first step should be to try with a good battery and with a feed run directly from it to the Boyer. You can then try substituting back and measuring voltage at kill switch, ignition switch etc. to find where the problem lies.

It only takes one dry connection somewhere under the tank or in the headlamp to cause this but my first suspicion would be the battery.

I have ridden tens of thousands of reliable miles with Boyers but they do have this sensitivity to voltage. it's much less of a problem once you know about it because it then becomes the first thing to check in the event of problems.
While low voltage could indeed be the problem, TIMING is one of the FUNDAMENTAL parameters that needs to be correct to have a well running machine. Low voltage is a secondary fault. Notice the author also said that the bike occassionaly spits back at take off. This could also be attributed to low voltage, or the FUNDAMENTAL timing. Secondary problems can be very elusive when the fundamentals are not right.
Hi Mark,

I'm with the rest of 'em, I had a similar problem with my bike or Boyer a while ago, and as soon as I set the timing to 31 deg. @ 5000 r.p.m. with a timing light it ran like a clock and without any fear of kickback.

I didn't need to use a degree wheel to get a good result but it may be of benefit to you, though it may be worth trying with just a mate and a timing light first.

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