regulator/rectifier

[transworld]

Hello,
I seem to notice a drop in voltage provided by the r/r when it gets too hot. Seems to perform OK after cool down. Did anyone noticed that? Is there a fix?
Also, did anyone take any measurement of diode resistance with a voltmeter? Would love to see the numbers so I can compare with mine.
Thanks a million!

 

[Robster]

Hey, interesting post.

Are you noticing the voltage drop when hot via the readout on the bike? And how hot are we talking, ie what kind of riding have you been doing and for how long when you've noticed the drop? Any issues with the bike cutting out or anything when this voltage drop has occurred?

I only ask as I recently suffered a "weird" electrical problem when the bike was very hot and one of my thoughts was that the Reg/Rec might be overheating. See my thread on here re Blowing Fuse F and see if it rings any bells for you!

I've still not got to the bottom of it and, though it seems to have cured itself now, I'll not be happy until I find out what caused it

 

[transworld]

Thing is I have been trying to troubleshoot a lack in performance that I think come from an electrical problem. As the bike heats up, i notice misses in acceleration, stalling as riding slow, etc...
On a typical highway ride, I would watch the voltmeter, and see that the alternator works fine, sends 13.5 to 14.2 through.
Trouble is when you are stuck in traffic, and the fan starts, then in a short amount of time, the voltage will drop a lot. If you were riding for a long time and you battery is completely full, you may not notice it. But in the case of long city driving when you are stuck for a long time, voltage would drop under 12, and you can deplete the battery pretty quickly. Also, I believe it could affect the fuel pump that is sharing the circuit with the fan, creating poor performances or small engine cutoffs. It will take longer also for the bike to accelerate on hot days, as if you had a slipping clutch.
Sometimes, after stopping, you will not have enough to start the bike again, which happened twice to me this summer. I changed batteries twice, have been troubleshooting this for two summers, but quite frankly, I am tired of spending the riding season trying to get this bike to run right.
So basically, you would have to drive and watch the dash voltage meter carefully to see if you get weird reading...

 

[GFJ]

Sitting here with someone who also has an xchallenge. Both his and mine have had the rectifier work loose; fixed by retightening the bolts with loctite.

Apparently they self unearthing so may lead to electrical problems if loose??

 

[transworld]

Possibly... Mine is tight. Planning on taking it off this weekend and see if i get same reading on the three diodes. I wonder if putting an additional spacer between the module and the bloc would allow more air to flow and keep the temperature in check.

 

[Losttheplot]

Pinkytiff had issues with his last year on our US trip. Long periods of slow riding in hot conditions caused the voltage to drop, to the point the bike wouldn't re start is stopped/stalled.

Funny thing was though, if left 20 minutes to cool down it was fine

My bike had no issues at all with regard to this. Though i do have the large Pace radiator fitted, and no touratech guard on the rectifier unit.

That said i I also had similar issues several years back, while my bike was stock standard. At the time i was trying to get up a slipppery chalk climb with Bakerman of this parish. The climb was slippery chalk steps and was just being a bastard, the bike needed clutching and pushing to try and make progress. In the end the bike acted like the battery was flat and refused to start. Again, it was left a while as i called for recovery, but then seemed to be fine again.

After fitting the new radiator i haven't had a problem.

 

[transworld]

Checked the regulator, everything seems fine. Checked the generator, each wire send 23V for a total of 69V to the regulator. not sure if it's weak or not...

 

[transworld]

On another note, it looks like the fan takes as much as 100W when running (manufacturer data). Seems like a lot on a 280W generator.

 

[GFJ]

rectifier for sale here

http://www.ebay.co.uk/itm/331358731567?_trksid=p2060778.m1438.l2649&ssPageName=STRK:MEBIDX:IT