boyer oh boyer

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Thanks for the reply Jason, no it is the 750 Highrider (1971). Would it be possible if the cable could be worn at the carb end? Guess I need to take the tank off and look things over. thanks again for the help. semper fi

In a word - "NO".

The cable has nothing to do with the symptoms you describe. Instead, you have an air/fuel mixture problem. Specifically, I believe your carburetors are set up too rich in the mid range.

Did Guest ever get his problem solved?

I got lost in this thread. Lots of opinions.

I have had a Boyer on my Norton for a looooong time. Maybe 15 years with the same box. I replaced the pick-up plate a couple of times. The only problem has been broken wires on the pick-up plate. They seem to break at the ty-wrap.

Guest's original problem was no spark on one side.

Are the coils wired in series?

If memory serves me - it's been a real long time since I had to fiddle with points- one set of points fires one coil, the other set of points fires the other coil. i.e.two parallel circuits powered through a ballast resistor.

Not so with the Boyer. Bypass the ballast resistor and wire the 6 volt coils in series. An open primary winding on either coil will prevent spark at either plug.

Check your total coil resistance with an ohm meter and verify it's within limits. (Not less than 5 ohms I think)

For road use, I'll take a Boyer over points any day. If I'm broken down on the side of the road with no spark - well maybe points are better.
71Commando 750 Increased Idle

Jason, thanks for the input but have a couple of questions on the fix-- will I need to remove the Carbs to fix this. Also while I have the carbs removed is there anything I could do to ensure smooth operation in the future i.e replacing anything. The bike runs great, just the idle starts to advance quit fast when stopped. If you want to email me my email is Thanks semper fi devildog

Personally, I would be very wary of messing with what you are about to mess with.

It is more likely to be just a matter of reading the manual RE: "tuning your twin carby setup" & getting that part right.

Make sure you have the twin carbys set up correctly as far as synchronising etc before you go changing slides etc.
I started this thread back in March and had no idea what a can of worms I was opening. To update everyone on my initial problem......I bought the Boyer from a dealer who sells them on E-bay... the Norton parts section. The dealer stated that there was a 5-year warranty on the Boyer system and requested that I send the black box back to him for factory replacement. This I did on April 6. Now I find that the dealer is waiting for another customer to send in another bad unit so he can get them replaced by the factory????? I guess that it's not cost effective to deal with only one bad box. At any rate, I could re-install the old points and auto-advance. but I couldn't get anything close to a steady RPM for timing purposes. I've got the newly resleeved carbs installed but want the timing as accurate as possible since I've already flunked the emissions test twice and can't get the bike re-registered until I pass. Sigh!!
Yup, no more ebay parts for me. I'm afraid I've learned the hard way.

So AZ has smog testing for motorcycles?? Even antique motorcycles? Ay caramba. Must be a nightmare getting an old bike like a Norton to pass. Nothing like that here in Colorado - yet. Just cars for the moment.

Wanna open up more cans of worms? Post something about Mikuni vs Amals or All Original vs modified :roll:

Your telling us you have to get an emissions test on a 30 year old motorcycle??
Even here in California, the land of over ambitious legislators and a very heavy handed EPA, we don't have to.
It' s hard to fathom.
Yep! Emissions tests for everyone! The best reason that I can logic out in a state where logic is a rare commodity is that because everyone around here can legally carry a hog leg; the emissions tests results in more clean and clear air, which improves visibility and lessens the chance of shooting the wrong vehicle while cruising down the freeway. I could be wrong. Actually, I probably am wrong since I work for the state.
Boyer Oh Boyer!

Jut a brief update on the Boyer woes. I got a replacement system and the problem presisted, namely-no spark on the left plug..So I realized that the problem had to be something else. from an old thread I wrapped both coils in plastic baggies and presto! there was spark! The thing that fooled me was that I had swapped the coils previously and each coil worked fine firing the right plug. A few months ago I had tried to check out the coils on my ohm meters (3 of them) and couldn't get a reading. I took the coils to AMR in Tucson, AZ. and the owner said that the coils were fine and my OHM meters weren't of a high enough quality to read them??? At any rate I will run the bike with coils in baggies until I can afford a couple of new ones. Since it seems that the power from the black box goes to the right side coil first, I can only guess that there is enough resistence in the black right to left coil cross over wire to keep sufficient current from reaching the left coil. Or the left coil was grounded out, or Sparky, the Lucas electric demon is messing with me. Actually, I have no idea what the hell is going on but I'm going to get new coils.
shorted coils

Hi Jack,

I may have been the one to suggest the baggies, but on a different string. What happens with the Lucas coils is they get clamped too tight then the case touches the wire on the inside shorting the thing. As long as you keep some insulation between your coils and the frame they should continue to work fine. Glad you found the problem!
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