Odd running when power to brush?

[xjwmx]

I might suspect the pickup or the tci, if the problem wasn't dependent on the brush. In the center of the schematic there's a 10 amp fuse. If the voltage there stays the same brush or not then the brush isn't having an effect on the tci. And the pickup is a different circuit. The pickup can be broken but what you do with the brush won't change it

the TCI box, but generally they work or don't correct?

From what I've read and my own experience when a tci begins failing typically the engine stumbles or just shuts down but you can immediately restart it and everything will be fine again for awhile.

 

[bobber33]

Here is my Logic so far is: the brushes only apply power to the rotor to create the electromagnetic field to work with the stator to actually create AC current to goto the regulator/rec to convert to DC and charge the bloody battery...Thats IT...
This should have NO affect on the ignition system whatsoever...

But somehow when the bike gets warm something is shorting... If it was the Stator shorting, the charging system would stop working, but the bike would run normally until the battery got low.

Rotor has been changed and same problem...

So this only leaves the pickup which is also a coil that happens to exist in the same general area as the charging system, even though its on a separate circuit the fact that its a magnetic pickup, also surrounded by the huge magnetic force of the alternator leaves me at this conclusion... BUT???? I'm not 100% sure...

Does this sound about right?

 

[xjwmx]

And it only happens warmed up. Sure.

 

[bobber33]

And it only happens warmed up. Sure.

Ya i tried it this morning cold and it was fine for a few minutes... both charging and running.
It got warm, then it started the dreaded seizure...

Went out for a few hours came back- fired right up - all good, 1 minute later same thing....

I ordered a deal ebay stator/pickup last night (sure i'll use it on one of the bikes) but my only other thought is that it could be the TCI box, so i guess we'll see what happens next...

Bike pics are located here by the way..
http://www.xs650.com/forum/showthread.php?p=35488#post35488

 

[xjwmx]

That's one route. I picked up a spare tci for $30 ebay. Or maybe just needs some tuneup work, like I said a couple posts ago.

 

[bobber33]

That's one route. I picked up a spare tci for $30 ebay. Or maybe just needs some tuneup work, like I said a couple posts ago.

how can it need a tuneup when it runs great and all the parts are new...?

 

[xjwmx]

It runs great until it warms up (significant new information from today). At this point it could still be nearly anything, except you've eliminated a few possibilities. Best next step is chill out with some good sippin' whiskey and see what the stator you've already ordered does for it. Plenty of Summer left in SoCal But at some point you will want to see what's inside the carbs you have and what your valve clearances are (I'm gathering that hasn't been done).

 

[bobber33]

I hear ya,, I'm already on the drink...
Carbs are new VM slide's. Re-jetted and working slick.
New cam, all valves adjusted, engine also rebuilt...
So the problem lies in some stupid little thing that isn't easy to find.. like a black box or a pickup or something less obvious...
Thing will run all day without a charging system. So makes lt hard to track.
Thanks for the help...
I'll post when i change out the pickup then the stator.

 

[xjwmx]

Could be intermittent short to ground in the stator when it's hot. Hypothetically ! I don't know if it can really happen. And I don't know what the effect of that would be. It doesn't need a tuneup, the wiring is ok, May be a pickup that doesn't like the heat. Maybe a tci going haywire coincidental to the bike warming up. Everything else was replaced. Not much else it can be really....

 

[bobber33]

PROBLEM SOLVED!
In an unreal turn of events the new stator and pickup showed up today.. i have no idea how it got here so fast.
But nevertheless, i quickly installed it and the bike is now running and charging perfectly without dying when it gets hot..
SO... no exactly sure if it was the stator or the pickup but at this point i don't really care either...
thanks all for the help and input on this odd problem....

 

[xjwmx]

Glad to hear it. Good intuition on the stator (or pickup?) If it was me I'd hook up the old pickup temporarily just letting the wire hang, to see which it was. I bought a stator with a pickup just to have a spare pickup.

 

[bobber33]

Glad to hear it. Good intuition on the stator (or pickup?) If it was me I'd hook up the old pickup temporarily just letting the wire hang, to see which it was. I bought a stator with a pickup just to have a spare pickup.

Yeah for sure.
As soon as i have time i will.

 

[xjwmx]

Unless the new pickup is slotted too, the old one will give you timing options. If it still has its original attachment screws, use a cutting wheel on a Dremel to make a screwdriver slot, and the screw will turn right out. You could even re-use it if you wanted. Non-slotted ones can be made into slotted of course.