Re: Self Combusting Rectifier - just caught it.
 

Ahh but on here when people are going to fire in and fix it themselves, the details are pivotal. Especially in electrics where you need to understand before you can diagnose. and it is hardly a complex system (thus confirming my views on dealer servicing customers ;))

TBH, in this case not much doubt that the reg rec needs replacing, since it was on fire :)


I do think the SV regs are pretty p*ss poor though. They're very old tech with a variable output, the MOSFET ones work a lot better. This can be seen just from the voltage output. The SV ones go all over the place, the modern ones sit at 14.2V, bang on.

Re: Self Combusting Rectifier - just caught it.
 

Just been thinking over how I was riding when the rf went puff. I've always been a big believer in machinery fails when its running style changes (my own little zen thing).

Basically I was crawling along in first (wouldn't normally be in first, because of a step bank in the road had to drop a gear, It had gone into 1st by mistake) with the clutch depressed the engine was reeving higher than sounds comfortable, normally within a second you would ease back on the accelerator. I let it reeve for about double that, about 3-4 seconds. I was in back street trying to find a shop. It was at this point I vaguely remember a "pssstttt sound". Back into second move off and thats when I smell (big nose) electrical burning / see acrid black smoke.

Another change to riding style was the 2200 miles (in 5 days) that I covered a few weeks back riding midlands - Paris - London. Once across the water my average speeds (70-90mph UK) where 80-110mph cruising.

Re: Self Combusting Rectifier - just caught it.
 

It makes no difference, if the reg was not happy giving you good charging at whatever revs you want... it was knackered.

Simply, reg needs to do its job from tickover to redline. Only takes one moment of 20V+ to completely fry your bikes electrics, ECU, clocks, lights the lot. Not safe.
This can happen at tickover, or that one odd time you rev it to 9k.

Re: Self Combusting Rectifier - just caught it.
 

Nowt to do with riding style. Mine has broken recently....and that started from it being layed up for a while. Its done 10k + of varying riding from constant peage speeds of 90+ for hundreds of miles at a time, to gentle bimbling to and from work of a few miles, over a three years. (not my sole bike)

They just go plop.

Re: Self Combusting Rectifier - just caught it.
 

My reg/rec went and took the battery with it. It now has a R6 reg rec in it, mainly because after receiving two duff pattern parts the guy who sorted it dug an old one he had out the back out and adapted it.

Haven't had any issues with it

Re: Self Combusting Rectifier - just caught it.
 

Its funny didn't the airlines say a similar thing about pilots flying style and over use of the rudder on American Airlines (this was how they were trained) and which was later proved to lead to catastrophic failure of the tail rudder.

You can never test for every possibility, a million monkeys and a million type writers (SV's) situation.

Hypothesis: When an already failing rf is exposed to un-loaded high revs in 1st gear for more than 3 seconds it may burst into flames ?

Re: Self Combusting Rectifier - just caught it.
 

I think you're failing to understand either what Chris is saying or how the system works. It doesn't matter what gear you're using or the road speed you attain or the load on the engine - engine speed is the only variable of the alternator.
It is possible that had you never ever revved it past, say, 5000 rpm and your regulator was not the best, then abandoned your former habits and had run the engine at a higher speed the resulting higher voltage could, note could, be the straw that broke the metaphorical camel's back.

Maybe.

Re: Self Combusting Rectifier - just caught it.
 

But if you never rev the bike past 5000 rpm then you probably eat fairtrade tofu and leave white stains wherever you sit.

I would bet you that reg was either overcharging the bike or undercharging it before it caught fire. Either way doing damage to your machine.

We will never know, but check your battery for swelling.

Re: Self Combusting Rectifier - just caught it.
 

As Y_C BEng I wouldn't know much about that ;)
You can't draw a parallel there, you've got a situation of stresses which something is designed to take, and the use going beyond designed in fatigue safety factors. End of the day, you put aluminium through enough stress cycles then it will snap.

You can test for every possibility, there aren't that many, it's not a 3d dynamic stress and fatigue problem which you need a million hours of FEA simulation to solve for an estimation of fatigue life. It's a charging system... use a multimeter... it will tell you SV regs are crap and to change it for a MOSFET type with clean connectors...

I'm not trying to be catty, but don't overcomplicate things.

Re: Self Combusting Rectifier - just caught it.
 

I suspect you're right. However I personally experienced a similarly fiery reg/rec failure about 15 or so years ago, up until that very trip everything had been fine, and even after putting the fire out the still well charged battery allowed me to finish the remaining 100+ miles of the journey. So whilst I suspect you're probably correct, there still remains the possiblity that it could, just possibly, have been OK right up 'til it popped.

Maybe.