Alternator Brush Longevity

Passx · Post by **Passx** » Mon Jun 09, 2003 1:09 pm

I'm curious as to what kind of mileage do you guy's get between brush changes ? My 80 had 12500mi. on it when I got it and one brush was worn out and the other was about 1/4 worn, the alternator worked sporadically. The 81 that I'm going to ride to Marlington this weekend has 13500mi. on it and all indictions are that the alternator is working fine, what do you guy's or gal's think ? Change the brushes ? yes, no , maybe ?

Steve P. #5220

sr71cbx · Post by **sr71cbx** » Mon Jun 09, 2003 2:44 pm

Passx,

Bring a spare set with you at least.......I always toss a set in the tank bag for long runs.

EMS · Post by **EMS** » Mon Jun 09, 2003 3:32 pm

Plus all the tools to change them... otherwise, they may not be very helpful

Coming back to the original question: 12K should not be enough miles to wear the brushes. Maybe somebody replaced the alternator before and the brushes had more miles on them. Funny thing though, I also observed significantly uneven wear on the brushes on my 79.

Jim-Jim · Post by **Jim-Jim** » Mon Jun 09, 2003 3:42 pm

Well, they will wear unevenly. The 'outer' brush has not only to travel further each revolution, it has to do it faster (like crack the whip

).

andy · Post by **andy** » Mon Jun 09, 2003 8:23 pm

Changed my original set last week, 21,000 miles. They had about 1/100" left. :eek:

broook · Post by **broook** » Tue Jun 10, 2003 7:23 am

I guess I must be lucky for a change. I bought my 80, 13 years ago with 28000 on it. Now I have 87000 with the same set of brushes. Don`t know if they were ever changed before I bought it but last winter when I checked them they were still good. Did change the bearings twice though.

Must be soft and hard carbon types.

Bob Brook

Newfoundland.

Passx · Post by **Passx** » Tue Jun 10, 2003 1:05 pm

Thanks Guy's, thats what I needed to know, I definitely am going to put a spare set in the bag since these bikes seem to eat them although the mileage's you gave me really isn't unreasonable and if thats all I have to do I'll be a very happy camper. I am going to add a shim to the clutch pack because it's started to make the ratchet sound sometimes when the throttle is blipped, curse those responsive Keihin's !! I figure I'll add a small amount to just minimize the ratcheting. Anyway thanks guy's it appears the brush problem may be overstated.

Steve P. #5220

Jim-Jim · Post by **Jim-Jim** » Tue Jun 10, 2003 11:21 pm

The brush 'problem' can never be overstated.

Everything I've ever seen written about the brushes boils down to "anything over 19K is time to carry a set" - (with tools to replace 'em on the road). If you loose the alternator on the road, you're running on the battery :twisted: - and no way to turn off the headlight.

Good luck if you don't have a set & tools

Hot Rod · Post by **Hot Rod** » Wed Jun 11, 2003 12:06 am

I changed out my originals in 1996 with 32,000 miles, they were about gone but I hadn't experiences any problems previously. Cheap insurance to carry along with the bike however.

last426 · Post by **last426** » Wed Jun 11, 2003 3:00 am

Gosh, I will be the first to say it. Replace those darn things and replace them every 10k or so. They only cost about 15 bucks, it only takes about 15 minutes, and they are a consumable just like tires. Why take a risk for 15 bucks? No big award for going 40k with an original set! At least that will put one of the variables on this bike to rest. Kim

RIPPER · Post by **RIPPER** » Wed Jun 11, 2003 10:07 am

When I bought my original 79 they said 8,000 miles and almost exactly that milage in Boise Idaho I looked down and saw my alternator wasn't charging.On my 80-81-and 82's I have OVER 20,000 miles and still haven't changed the brushes.I'd be MORE concerned with the BEARINGS seizing up.If it's gonna be a long ride,change the bearings.

Guest · Post by **Guest** » Wed Jun 11, 2003 3:28 pm

How easy (difficult) is it to change the Bearings? Any special tools required? Any trick methods?

RIPPER · Post by **RIPPER** » Wed Jun 11, 2003 3:35 pm

Put the new bearings in the freezer for a couple of days.The old bearings shouldn't be to bad.The one in the cover may fall out if you slam the cover on a flat surface or you may have to heat the cover and it will drop out.

E Lee · Post by **E Lee** » Wed Jun 11, 2003 8:29 pm

If you have to change the brushes make sure when you screw the bracket back onto the cover the wire leads clear the bracket mounting bolts; otherwise you will have it all together and as soon as you turn the key the main fuse will blow.

Another point after reading Tech Tips, replace or resurface the A & B plates. Just adding another washer does not solve the noise rattle.

Later,

Ed

sr71cbx · Post by **sr71cbx** » Wed Jun 11, 2003 8:56 pm

------My '79's original brushes went tango uniform at 5,855 miles,and Honda dealer in Sacramento picked up the tab on that one,as it was still under warranty and I had 375 miles to ride to L.A.-------I keep 'em replaced about every other year,as it is a bitch to get at now with turbo plumbing in the way........

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