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I have restored a 70 Bonny. Installed a Boyer MK3 ignition. 6 volt coils. Everything seemsto be wired properly. Problem is that after running about 100 miles the bike starts to run like crap. Battery seems to lose charge. Checked charging system and all looks good. Putting out 14.5 volts +. After sitting for a while the battery drops voltage. I have checked and rechecked the wiring and nothing is miswired.Battery is new. The only thing that was not new on the bike is the stator. Would a new high output stator solve the problem. Am putting it away for the winter now and want to ride this thing as trouble free as is possible next year.
 

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First check your meter, despite being scaled to three decimal places they can often be a volt or two wrong. ok 1.999 of a volt wrong.
I think 14.5 volts or more is too much, check the electrolyte level in all cells. then check connections, especially the connections to ground. Lastly check that the zenner diode is holding the voltage below 14, I would expect to see 13.5 max.
if you want reliability coupled with the possibility of starting easily with a flat battery, convert it back to points.
 

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With all due respect, I must disagree with Panda. Your charge voltage is correct. Also, if your meter, either a VOM or DVM, is off 2 volts, can it Janet! That is a major POS. I have never seen any meter off by 20% in my 55 years of playing with electricity. 5% maybe, but 20%, nope. I will agree with Panda that you may have a connection problem or that your electrolyte is low, very low.

Also, if points were the cat's meow, Ferrari would still be using them, as would Honda. Electronic ignitions rule in reliability and performance. I have started my Boyer equipped bikes with a dead battery by lots of kicks. Good strong healthy kicks.

I also must disagree with your statement that you restored your bike.

Well, I guess I'm being disagreeable tonight. =!8^)
Look up "too restore".

OK, back to the real problem.

If the battery "dies" after sitting with that charge voltage:
1 - Your battery is punk. Yes, even a new battery can fail in a short period of time. Put it on a good charger overnight, take it off and measure it 5 or more hours later. It should be >12.6V. if not, you have a cell that has failed or is failing.

2 - Something is "ON" even though the ignition switch is off. The easy way to discern this is to put your DVM in series with either battery lead in the maximum current position. It should be 5A or more. If you see any current reading, you have a problem to solve.

You can check out my vehicle website, see the sig, or another one of my websites, http://www.w3ab.org. I think I still have a treatise on charging & batteries on it. Otherwise PM me and I'll shoot you one.
 

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Discussion Starter #4
70 bonny

Thanks for all the info guys. What I have done so far is I have taken advise from others in trying to hunt down the problem. One thing that I did was to disconnect the battery and put my multi meter in its place. Then turn it on set at an ohm scale. If there was a bleed off of power somewhere, I should get a reading as there would now be a closed circiut somewhere.Everything works as it should. No reading with the key off and a reading or completed circiut with the key on. I can check the grounds again but all threads were cleaned with a tap to ensure a good ground at that point. I give you that I didnt "restore" the bike but it was completely rebiult to as factory stock as was possible with the resources that I had at the time.

Virbration is just a frame of mind
 

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That is a good start.

What is the battery voltage after being off a charger for 5+ hours?

You said you chased out the threads but you really don't want to ground through the threads. Corrosion can develop and then you will get a connection problem that will be difficult to diagnose. An ohmmeter with show a "good" connection but when current is drawn through the "good" connection, the resistance will cause an IR drop that will lead to a "not run well" condition. If the frame has been powder coated, you'll want to scrap the coating away and use a SS internal or external thread lock washer between the lug and frame. If it is just painted, scraping would be best but not necessary, unless there are layers upon layers of paint.

BTW, what was the resistance when your ignition switch was open, and closed?

I coined a word years ago when I would "restore" a customer's vehicle to be better than new with performance and/or reliability enhancing mods, it was restified.

The GP would oh & ah over the vehicle while the cognoscenti would catch some of the mods. :p
 
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