Alternator strip ??

Pukmeister

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I recently had an issue with a (briefly) squealing alternator belt after a cold start, which cleared itself.

Two weeks ago I removed the alternator during a front shock refurb to find the underside of the alternator casing fins had cracked due to corrosion of the laminated core. I bought a spare alternator on eBay from Arizona of all places, its mint. I decided to refit the cracked alternator as the new one hadn't arrived in time and I needed the bike on the road for my commute and the old alternator still worked fine after a free-up of the pulley and a good dousing in ACF50.

Over the past few days I have had the odd brief battery icon and yellow/red triangles plus lampf and abs warnings. Leaving work today I had a slight squeal plus the red/yellow alarms, no speedo, abs fail and lampf warning until about 6 miles up the motorway when it all reset and worked normally. I presume my alternator had partially seized then freed itself up. The alternator drive belt is new, having been replaced during the shock refurb work.

Has anyone stripped/cleaned/rebuilt their Denso alternator and if so, can you offer any advice?

I can always swap out for the new(used) alternator which appears mint but if I can extend the life of my existing item then so much the better. Any help is much appreciated.
 
Cheers Mike, in that case I may have to postpone the R1 from enjoying its winter slumber this week whilst I strip out the GSA front shock again and replace the alternator. I wouldn't mind but my bike has only done 38,000 miles in 8 years despite near daily use and a few European tours.

Reliability is paramount as I'm off to Spain on her next April and don't fancy getting stranded somewhere with a flat battery and a seized alternator.

I might strip down the old alternator in slow time and see if I can skim out the stator housing by a thou or two to make it a viable spare.
 
If the casing is cracked throw it in the bin. It will only let you down if you try and press it into future service.
 
Mine made a sound like a dry bearing which stopped as (presumably) it warmed up. Since then Ive had a squeaky rattle that comes and goes. I doubt that particular alternator will still be there by next spring.

On eBay the Denso type is quite a bit lower cost than the more powerful Bosch. But with LED and HID lights I probably don't need the higher power.

Edit - Scrap that they all look about the same cost though one from USA is much cheaper even including delivery.

Has anyone fitted a car alternator? On eBay, used Ford Fiesta types are about £25 while the R1200 type is around £100.
 
Mine made a sound like a dry bearing which stopped as (presumably) it warmed up. Since then Ive had a squeaky rattle that comes and goes. I doubt that particular alternator will still be there by next spring.

On eBay the Denso type is quite a bit lower cost than the more powerful Bosch. But with LED and HID lights I probably don't need the higher power.

Edit - Scrap that they all look about the same cost though one from USA is much cheaper even including delivery.

Has anyone fitted a car alternator? On eBay, used Ford Fiesta types are about £25 while the R1200 type is around £100.
Don't know about car alternators but mod to fit the Bosch unit if you can get one
 
I going to guess that the fittings from any car alternator will be nothing like your bikes
 
I going to guess that the fittings from any car alternator will be nothing like your bikes

And you would be quite correct in your assumption.

The GS/GSA alternator is solidly bolted to the top of the engine on three pedestal feet of unequal length, it can only be for BMW hex head engines as it wouldn't fit anything else by the looks of it.
 
Don't know about car alternators but mod to fit the Bosch unit if you can get one

I have the Bosch type which seems is gradually destroying itself. I don't need the last 100w of power, so if the Denso is as reliable I may as well save the additional cost of the Bosch.

Car alternator absolutely have different fittings. Just wondered if anyone has tried making brackets.
 
If you can get them from a dry sunny USA state for £60 including shipping and taxes like I did, going to the effort of modifying a car alternator seems like a lot of work.

(That said, I haven't quite finished refitting the fuel tank to prove my new alternator is good. A Sunday morning job.)
 
If you can get them from a dry sunny USA state for £60 including shipping and taxes like I did, going to the effort of modifying a car alternator seems like a lot of work.

(That said, I haven't quite finished refitting the fuel tank to prove my new alternator is good. A Sunday morning job.)

I agree. Keeping a watch on eBay.com

The car alternator would be kept standard with a bracket plate. But - there are lots of buts. So eBay it is.
 
Alternator replaced and tested, took about 3 hours going slowly. All good again.
 


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