dynamo

[RichardL]

A101960,

Thanks for the expansion. Yes, it makes sense that bad segments could be passed over while motoring. Not that it means the dynamo is good, but, when running on the engine, those same bad segments are passed over while the good ones would be generating. All this because Faraday's Law is a two-way street.  In the case of my dynamo, it motored and generated, which was a lucky coincidence. In the case of Franenstein's dynamo, it is rather clearly in trouble, so, despite my apparent mistatement of indicating a good unit, it would still be revealing to know if it motors. If so, and it is truly bad, it certainly would be an empirical proof of your point.

Richard

[Brian]

Hopefully I have done this correctly, follow this link. This guy has rebuild kits for most dynamos so if you want to have a go at reconditioning your own dynamo you can get everything you need.



http://stores.ebay.com.au/ftw-motorcycles53_W0QQssPageNameZstrkQ3amefsxQ3asstQQtZkm

[LJ.]

Yes there are a few people selling the parts now, indeed I have replaced my armature on one of my bikes. However, replacing the field coil with a new one requires a special tool. It has to be pressed into place correctly so I understand. No problem in replacing the old one once removed as its already taken its shape.

(Correct me if I'm wrong someone)

[frankenstein]

ok....folks....i have done a full strip down of the dyno today and cleaned and inspected after doing the rotation bench test which went great and the dyno rotated fine when conected to a 6v battery....on inspection the brushes where ok for wear...but in my opinion a bit soft and will need replacing at a later date.....i have cleaned the copper commutator carefully with the fine emery cloth as it was almost black.....all conectors have been checked and wd 40 worked a treat on cleaning the insides as the dyno was filthy ..... i bolted it all back together and hey presto the test bulb lit up great...problem fixed for now...fingers crossed.....i now will be ordering one of those solid state regulators before using the bike again....now to fix the oil leak from the timing side case....i just knew things had gone to well.....thanks to every body in the forum for your advice !

[RichardL]

Great news.

Will you be buying the Manotec DVR2? I am very interested to hear how that goes for you. So far, there are many good reports of it on this forum. If I start frying batteries again, I will likely go that way.

Richard

[frankenstein]

hi richard
               ii have just ordered the  Manotec DVR2 positive earth..you can pay via paypal from there website which is very easy...report to follow after fitting...cheers....frankenstein

[frankenstein]

dynamo bit the dust again....aaaaarrrrrggggghhhhhhh !....is it possible to remove the carbon brushes or check them whilst the dyno is still on the bike to avoid removing the timing case cover

[RichardL]

I believe it is, but I am sitting at a desk right now and not in front of my bike. The difficulty might be getting an angle on the terminal screws so that you access them with a screwdriver. Not to state the obvious, but I assume you have checked that the brush leads are properly insulated and not getting pinched by the cover or the like.

[a10 gf]

Sorry for all that trouble. Here is what I did to get control, much easier to sort out the gremlins than when it's on the bike! It's the complete bike wiring duplicated (in a haste, looks like a mess but worked fine) when I lost all charging once upon a time.

http://www.a7a10.net/BSA/techpics/powertest.jpg

[LJ.]

Yes it is possible if you have the large end cap, but if you have the bakelite end cap and band then its a bit more awkward, can be done but be prepared for some sweat. If you have the latter then make sure that the band nut and bolt part is not shortening out on one of the brushes.

[RichardL]

Erling,

Were you able to set the alternator with the digital meter? I thought the idea was to use the moving coil so you could detect, with greater precision, the exact point for adjustment. (Don't ask me without a book in front of me what that point is.)

Richard

[Brian]

Just on the subject of fitting the field winding. The manuals show a special tool to hold the winding tight while you do up the screws. I use a lump of brass the same diameter as the armature held in the vice. Slide the body with winding over this and use a hand held impact driver. Give the screws (use new ones) a couple of good whacks. I have done several over the years like this and never had a problem.

Erling, I hope thats not the kitchen table underneath your test bed !!!!!!!

[a10 gf]

Were you able to set the alternator with the digital meter?

I suppose you meen the regulator, yes, did adjust well with a multimeter, trying to follow most of the lucas instructions.

I hope thats not the kitchen table underneath your test bed

No. It's the living room table! (had the house for myself for a period)

[frankenstein]

is it easy to rebuild a dyno...do i need any special tools...i took mine apart ok as far as cleaning....i did not remove the field coil or any bearings....hawker do this rebuild kit http://cgi.ebay.co.uk/BSA-A7-A10-E3L-Dynamo-Rebuild-Kit_W0QQitemZ180290428673QQcmdZViewItem?hash=item180290428673&_trkparms=72%3A12%7C39%3A1%7C66%3A2%7C65%3A12%7C240%3A1318&_trksid=p3286.c0.m14 

or will do an exchange for £165 any advice would be great

[RichardL]

Erling,

Yes, of course, the "regulator."  Brain (not, "Brian") must have fallen asleep while fingers continued to type.

Richard