how long do brushes last ?

[Isamemon]

Thinking of preventive stuff and just reading the thread on Omeega alternators. I bought my bike from the original owner. In the 38k miles he had it ( 78 r80) he replaced the brushes twice and he gave me a set of new ones with the bike. He gave me the two sets of old ones, and all the old plugs and points, etc, even used filters :dunno . Now with 48k on the bike, should I be replacing brushes ? Was he just replacing to be preventive ? How many miles are the original alternators good for ? Cant ask him now, he has passed on.
No extra electrical on the bike, charging just fine now.

[Rod Sheridan]

I replace the brushes when I get down to about 2mm of free length left.

If memory serves me, I replace brushes every 10 years on my bike, Diann's bike has gone 22 years without a brush replacement.

Age and mileage aren't very good indicators of brush life, X billions of revolutions would be a better measurement.

Regards, Rod.

[rpeckham136133]

It sounds like the old ones should do fine for quite a while. They seldom fail suddenly, rather you will get some charge/no charge occasionally. You can look at them, pull them up and see how they compare in length to your new ones. Easy enough to change, but probably not necessary.

[Isamemon]

thanks
it must have been preventative stuff he was doing as he rode the bike twice from Oregon to New England. But he did have charging problems at one time he told me, but was related, he thought, to using original BMW battaries, as he never had a problem again when he went aftermarket.

[20774]

I replace the brushes when I get down to about 2mm of free length left.

I'm having trouble picturing how short this is. What I mean is, that seems incredibly short for the brushes. The number of 13mm sticks in my head...basically, if they're shorter than 13mm, it might be time to replace them. More importantly, is what kind of pressure the snail spring has on the brush. It can be original length but with little pressure, you might have a charging problem.

I've got 90K on my brushes...I'm considering replacing them, but haven't gotten around to it. Bike still charges fine...no real problems just yet...

[Rod Sheridan]

Hi Kurt, that's 2mm of free length left, not overall length.

ie 2mm of travel remaining.

Regards, Rod.

[DARRYL CAINEY]

Thinking of preventive stuff and just reading the thread on Omeega alternators. I bought my bike from the original owner. In the 38k miles he had it ( 78 r80) he replaced the brushes twice and he gave me a set of new ones with the bike. He gave me the two sets of old ones, and all the old plugs and points, etc, even used filters :dunno . Now with 48k on the bike, should I be replacing brushes ? Was he just replacing to be preventive ? How many miles are the original alternators good for ? Cant ask him now, he has passed on.
No extra electrical on the bike, charging just fine now.

Just replaced mine after 455,000 miles and a Omega System.

Darryl