Triumphrat

verno · 04-27-2008

I just recently rebuilt my 69 T100R from the case up. She started on the the very first kick, but shortly thereafter started to run worse as the bike heated up. The right side dosent fire unless I really crack the throttle, and when I park it, I hear a humming sound from in the case,(the generator I would guess) now the battery wont even hold a charge. I'm running a boyer unit. Anyone have any clue?

OzBloke · 04-27-2008

Verno,

I have a number of queries that I'd like you to respond so we can assist in finding your problem.

When you say the battery won't hold a charge, how do you determine this (eg measuring voltage over time?, in the bike or on the bench?)

Did you put a new battery in, and bench charge it before it went in the bike? What type?

Do you own a multimeter, or can you get you hands on one? If so, please do a quick test with battery out - with meter on resistance ranges (ohms), every switch on the bike turned off, and working from highest to lowest ohms range, measure between the connectors that would connect to the battery if it was there. This is not the battery itself, but a test of the wiring. Once measured one way, swap the meter probes between cables and measure again - let me know the results.

How many wires coming out of the casing where the alternator stator fits - 2 or 3?

If you charge the battery on the bench, and then put it in the bike, do you get sparks when you connect it back up to the wiring (with everything turned off of course)?

What's your engine number?

Anything special added to the bike (electrics) besides the Boyer? Like a rectifier/regulator?

What configuration of coils are you running with the Boyer? 2 x 12v, 2 x 6V, or a double-ended 12V?

Please email or PM me your email address, and I'll send you a document that may help with electricals.

verno · 04-27-2008

thanks... so far I've only had it on the charger with the battery on the bike, it's a 12V sealed unit, and as for the engine # it's T100R XC C7400. I know it's a positive ground set up and I don't know much else yet, I'll get the rest of the #'s tomorow after work. thanks for replying, I've been pulling my hair out trying to get her on the road for the summer time.

NHOJ from Maine · 04-28-2008

my disclaimer:
i'm no electrical wizz..
but have a '69 T100s, with a boyer unit..

it sounds like 1 of 2 kinds of problem..
either the boyer is not getting enough juice, or a side specific spark problem..
assuming the wiring is stock, and properly hooked up, including boyer unit, I would try starting it with the battery is being boosted. (hooked up to the charger or larger battery.) if problem goes away, something wrong on the charging side.. with bike running, you should see 13-14V across posts with multi meter.

if no differance while boosted, I would try to transfer the problem to the other side, to track down faulty component. start with plugs, then plug wires, then coils to see if problem can be transfered to the left side.
if you succeed in transfering the prob, you have found your fault.

the buzz you hear might be coming from the coil(s).

boyers can be tempermental without enough juice.
swap to new plugs.. many times as simple as the plug.
use non resistor plug wires... big differance on old bikes.

good luck. -J

verno · 04-28-2008

I finally got ahold of a multimeter. I charged the the battery till it it was full and it read 14V, when I turned the lights on it fell to 6 and a half. and only went to about 11 after the lights were turned off. I put the bike back on the charger to start it, and even that was a struggle. It was idlling very rough and did not want to rev up. I pulled off the coils and could not ID them, there was no definite 6 or 12 on them, just LUCAS stamped on the top. After trying to kick the motor over a few times I still get a weird humming from the bike. The bike dosen't have a generator but a stator located in the primary case and that has 2 wires. When the bike is idlling, the battery reads about 14V.

OzBloke · 04-29-2008

Verno,

Firstly, your battery is pretty close to being stuffed. Being a sealed unit, not much you can do except to try to discharge it to 10V under a light (ie not heavy) load (eg 21W 12V light globe), and re-charge it to 14V, but this may take 10-15 goes to get it back to a semi-usable condition - it will never be trustworthy again. Better off replacing it with a maintenance free AGM type. Charge on the bench for 4 hours or so at less than 1 amp before putting it in the bike. NEVER use a 4-6 amp car battery charger on a bike battery - it will cause serious damage.

Next, you need to check your rectifier - use the instructions in the doc I sent you, or spend $5 and replace the current one with a solid state one - 20Amp Bridge rectifier. If the rectifier is cactus, or even if one diode out of the four is bad (shorted), it will cause rapid discharge of the battery, poor or no charging, and backflow through the alternator stator winding (very bad).

The problem is the Boyer is not getting what it needs to run properly - a consistent voltage about 10V, and current source to switch the coils on/off. As soon as it starts to switch the coils on, the current draw from the weak battery causes the volatge to drop below 10V, and the Boyer quits, which allows the volatge to rise, the boyer swicthes back on, tries to run the coils, etc etc - could be the buzz you hear.

Once you've replaced the battery, and are totally satisfied the rectifier is OK, use NHOJ's swap method to isolate one particular component if you're still having problems with one side.

Hope this helps.

Pete

verno · 05-03-2008

I finally replaced the battery with a brand new sealed unit ($135!!!), and it started up on the first kick, was getting around 12-13 on the multi-meter, then did the head light test, and went back and it started again with no trouble. Both cylinders are firing well now but the right one still takes longer to warm up, I'm hoping this might just be a plug issue.

OzBloke · 05-03-2008

The "one side takes longer to warm up" issue is more likely to be mixture related than electrical.

Good job on the battery - did you test the alternator/rectifier?

Pete