talking of alternatives for Rotax 912, what about starter motors and stators?

[danny_galaga]

That's a two brush starter. What did you do for the third brush? Or were they ok? Can narrow down those kits to a f650 or vx800 starter. If you need to change the brushes for instance, there can be different compounds. That can make a huge difference. For instance, the only difference between a 12v 40mt truck starter and a 24v 40mt truck starter was the brushes, and you didn't undercut the commutator bars. 

[John Nooyen]

I'm sure the starter only has 2 brushes.

Possibly my last engine was an old one.

 

Try matching something from ebay. 

The starters appear to be Yamaha.

The Yamaha unit was identical.

[John Nooyen]

Try 

 

https://www.ebay.com.au/itm/313440462958?_trkparms=amclksrc%3DITM%26aid%3D777008%26algo%3DPERSONAL.TOPIC%26ao%3D1%26asc%3D20221102144041%26meid%3D1110632c0ac24e4fbcb5378303eacdde%26pid%3D101251%26rk%3D1%26rkt%3D1%26itm%3D313440462958%26pmt%3D1%26noa%3D1%26pg%3D2380057%26algv%3DPersonalizedTopicsV2WithWatchlistFeaturesAndTopicMLR%26brand%3DArrowhead&_trksid=p2380057.c101251.m47269&_trkparms=pageci%3Ab6c5363d-d8c8-11ed-a70b-9eb240a64fe9|parentrq%3A72dba0c31870a9b13962c596ffffa390|iid%3A1

[facthunter]

Starter brushes are metallic as wellas some carbon and very low resistance. because of the large current involved, Starters  aren't trouble free by any means and a new one is the way to go. Its also generally not economical to overhaul  the smaller Alternators when new ones are available at a good price with no delay often cheaper than a repaired one.  Nev

[danny_galaga]

You know, I've thought about it since more, and I'm tempted to buy that German after market F650 starter for shits and giggles. If it turns out to be not useful, it will be easy to sell on...

[facthunter]

Have you got a price on one?.,  nev

[danny_galaga]

6 hours ago, John Nooyen said:

I'm sure the starter only has 2 brushes.

Possibly my last engine was an old one.

 

Try matching something from ebay. 

The starters appear to be Yamaha.

The Yamaha unit was identical.

Apologies. I could have sworn I saw 3 somewhere! 

[facthunter]

3 brush is in earlier type generators. The 3rd one is smaller and only "decides" how much current to the field coils and that  controls the output. Maybe big truck starters have extra brushes but I "think" they would be an even number with more than 2 poles. and field coils.   The windings are often strips rather than normal wire.  Nev

[danny_galaga]

2 minutes ago, facthunter said:

3 brush is in earlier type generators. The 3rd one is smaller and only "decides" how much current to the field coils and that  controls the output. Maybe big truck starters have extra brushes but I "think" they would be an even number with more than 2 poles. and field coils.   The windings are often strips rather than normal wire.  Nev

Most car and truck starters have 4 brushes. Some of the smaller Nippon Denso car starters had 3. Maybe I was mixing up that memory with something I'd seen recently! I never knew why 3 when I was an apprentice but I'm thinking it would be a way of increasing resistance for a lower current draw on existing 4 brush designs. Why not two then? Haven't the foggiest 😄

[danny_galaga]

Oh actually, I think maybe two on one side and one on the other because one of the poles (I want to say +) might run hotter...

[facthunter]

EVEN Pull would be best or you'd get more bearing wear. They only have plain bearings and  armature Polling is disaster  Nev.

[danny_galaga]

37 minutes ago, facthunter said:

EVEN Pull would be best or you'd get more bearing wear. They only have plain bearings and  armature Polling is disaster  Nev.

It's a very small force compared to everything else going on in there. A lot of the 2 brush jobbies are 90 degrees to each other. 

 

On my accusation of a RO-tax on the starter. Maybe I was too harsh. Here's the price for the similar Suzuki starter mentioned earlier 😲

 

https://www.cmsnl.com/suzuki-vx800-1990-l_model14275/partslist/FIG-23.html#.ZDZm6WR_U0E

 

Price for that after market one is about $210 including freight as far as I can tell. 🤔

 

Edited April 12, 2023 by danny_galaga

[danny_galaga]

Looks like the latter Rotax starters are 4 brush, and the earlier black starters are 2 brush

[facthunter]

All depends on the circuitry of the armature  and the cost of making  them. I think you'll find the cost is not high if you get them from the right place(s).  Nev

[danny_galaga]

Damn it was hard to find a 3 brush starter example. I thought I was losing my mind 😄

[facthunter]

Cheez they couldn't look much crappier. See the copper in the brushes.? Have a look at older DELCO starters. for quality. RR at one stage used DELCO electrics.

[danny_galaga]

5 minutes ago, facthunter said:

Cheez they couldn't look much crappier. See the copper in the brushes.? Have a look at older DELCO starters. for quality. RR at one stage used DELCO electrics.

Yeah that pic seems to be an aftermarket part from Turkey. Delco were ok. My own personal opinion was that Bosch were the gold standard in quality. Nippon Denso weren't bad (and as we are noticing on this little journey, quite ubiquitous on small engines). 

 

At the bottom of the heap in terms of design and or quality were Lucas, prestolite, magnetti Martelli and Hitachi

 

There were niches of course. CAV made really good quality truck starters, albeit complicated. Bosch next in truck starters, then Delco. Delco weren't bad mind you. Just a bit simpler. Easy to overhaul though.

 

 

[facthunter]

Starters that crank over the larger Harleys have a big job to do. They are pretty BIG INCH motors today. Bentley and RR used  Delco post WW2. LUCAS would be the alternative. . Nev

[danny_galaga]

47 minutes ago, facthunter said:

Starters that crank over the larger Harleys have a big job to do. They are pretty BIG INCH motors today. Bentley and RR used  Delco post WW2. LUCAS would be the alternative. . Nev

I think they use reduction gear starters now. Pretty sure my Victory did. At one stage Harley were using Hitachi starters 😄

[nomadpete]

On 10/04/2023 at 10:14 AM, danny_galaga said:

Phew!

 

That was a lot of work, not even going TRY to look for the stator or rotor. You guys can do some research there 😄

 

When I replaced my stator assembly, it was clearly labelled 'Ducati'.

No idea which ducati, though.

[BrendAn]

10 minutes ago, nomadpete said:

When I replaced my stator assembly, it was clearly labelled 'Ducati'.

No idea which ducati, though.

i know the 582 uses ducati ignition

[danny_galaga]

I am dismayed that Rotax are using parts from the most fragile motorbikes on earth 😄

[RFguy]

But not too many of them (rotax) stop.

The failures of the ignition modules though was a real FU by Rotax and shows where they are good, and where they are not. Stacking two ignition modules hard on top of eachother in an area of high temperature was just asking for trouble.  A 10mm gap between them would have ensured cooling.  In my opinion, electronics is an area NOT to trust Rotax due to their demonstrated incompetance. However, they have demonstrated competance (to me) with the hard to get right stuff like pistons, heads, cooling, gearbox.  The inlet manifold is a bit of a compromise (mixture variance front and rear at low gas velocities ) but its bearable. The dual carb is fiddly but acceptable. 

Edited April 18, 2023 by RFguy

[danny_galaga]

Yes, I didn't even worry about getting the Rotax supplied regulator. Got a better one, and it even has less wires to worry about. Less is more as they say...

[Area-51]

Magnet Marelli and next Lucas were always the winner and first choice for everyone in europe...

 

They were guaranteed to fail at dusk; leaving the rider/driver at the side of the road to be rescued by the farmer on their tractor who would offer a fresh stable to sleep in and to affect repairs... And the farmer always had daughters to make the whole adventure complete...

 

So failure was not frowned upon in the old days... 🤷🏼‍♂️