Starter Motor Zane Twin

[Reaper66]

HiI have a 759 S Zane twin & recently purchased a new starter motor from the USA - I asked the obvious questions prior to purchase but although it fits perfectly- The motor turns in the wrong direction!!!!
Does anybody know if I can change the direction of turn by swapping the polarity inside the starter??
Cheers
Ian

 

[Cosi]

Sound like a Ducati starter motor

 

[Sir Sidney Ruffdiamond]

Mmm not sure - as above it’s a Ducati item hopefully @ mgordonvegas may know - you can use the Ducati parts 4 brush set up but this needs reversing to work with a Zane from memory

 

[Laverdalothar]

Did you ask the seller? I would simply give it a try.

 

[Reaper66]

Sound like a Ducati starter motor

Yes I have since discovered that the serial.number says its a ducati starter !!

 

[Ventodue]

HiI have a 759 S Zane twin & recently purchased a new starter motor from the USA - I asked the obvious questions prior to purchase but although it fits perfectly- The motor turns in the wrong direction!!!!
Does anybody know if I can change the direction of turn by swapping the polarity inside the starter??
Cheers
Ian

Hi Ian and welcome to the forum,

There is another way - and as I understand it, this is how Denso did it. Here's the explanation that I was given many years ago:

"The trick is not to reverse the brush polarity, but to move their position relative to the stator.

A series wound motor works by the stator (fixed) magnetic field repelling / attracting the armature (rotating) magnetic
field. So, say there are 12 electro magnets on the armature. Moving the position of the brushes by 30 degrees (360/12 = 30 ) would reverse the polarity of the magnetic field and the motor would go the other direction.

Eureka! It's as simple as that!"

And indeed the brush holder plates are not the same, Ducrappi vs. Laverda, and this sems to be the essential difference between the two starter motors (the brush plates have different Denso part numbers, for example).

So to fix your problem, try replacing the Ducrappi brush holder plate with the one from your Zanè.

(Unfortunately you can't use the Ducrappi brushes in place of the Laverda ones because the wires are connected to the brushes in such a way that they get in the way of the case. Damn!)

 

[Reaper66]

That makes perfect sense to me- thank you for sharing your knowledge.
I thought that there would be a way around the issue.
Cheers
Ian

 

[Sir Sidney Ruffdiamond]

That makes perfect sense to me- thank you for sharing your knowledge.
I thought that there would be a way around the issue.
Cheers
Ian

Hi Ian Got a friend looking for a starter for his Zane in UK - could you share the part number and the source of your starter - also interested in the brushes - are they curved to match the commutator

 

[Ventodue]

Hi Ian Got a friend looking for a starter for his Zane in UK - could you share the part number and the source of your starter - also interested in the brushes - are they curved to match the commutator

Ian will surely correct me if I'm wrong, but here's a picture that should reveal all. The Ducrappi number is the 270.4001.1A, the Denso number the 128000-6050. (FWIW, the Denso reference for a Laverda starter is 228000-6520).

Ducrappi models that used this starter are numerous, too many to list here, but include Monsters and ST2-4.

To the best of my knowledge, the brushes are, most regrettably, not the same. Altho' someone may soon come along to correct me on that ...

However I do have a note from way back that the starter plate - and therefore presumably the brushes - from BMW K75/100/1100 may work. But I can't vouch for that.

 

[Paul Marx]

Brushes can be shaped to suit with a good set of teeth.
Paul

 

[Sir Sidney Ruffdiamond]

Ian will surely correct me if I'm wrong, but here's a picture that should reveal all. The Ducrappi number is the 270.4001.1A, the Denso number the 128000-6050. (FWIW, the Denso reference for a Laverda starter is 228000-6520).

Ducrappi models that used this starter are numerous, too many to list here, but include Monsters and ST2-4.

To the best of my knowledge, the brushes are, most regrettably, not the same. Altho' someone may soon come along to correct me on that ...

However I do have a note from way back that the starter plate - and therefore presumably the brushes - from BMW K75/100/1100 may work. But I can't vouch for that.

Thanks for that - he has used some BM brushes on his starter but the motor seems to give the impression of one of the phases not working - ie turns the engine then nothing then clicking - starter has been out for new brushes . Bike runs fine when started

 

[Zacgrief]

Thanks for that - he has used some BM brushes on his starter but the motor seems to give the impression of one of the phases not working - ie turns the engine then nothing then clicking - starter has been out for new brushes . Bike runs fine when started

I have the same issue with BM brushes on mine. The BM brushes when new are square ended but the original Lav brushes match the diameter of the armature (not sure if this is wear or they are formed that way to pick up on more segments and give more torque?).

 

[Ventodue]

Thanks for that - he has used some BM brushes on his starter but the motor seems to give the impression of one of the phases not working - ie turns the engine then nothing then clicking - starter has been out for new brushes . Bike runs fine when started

"Clicking" sounds weird (no play on words intended). Dunno what would cause an electric motor to click. A solenoid yes, but a starter motor?

It's not just getting stuck, by any chance? Does it get hot, do you know?

 

[Zacgrief]

"Clicking" sounds weird (no play on words intended). Dunno what would cause an electric motor to click. A solenoid yes, but a starter motor?

It's not just getting stuck, by any chance? Does it get hot, do you know?

Clicking is the solenoid yes not the starter but starter not rotating is the issue. I am convinced its due to the ends of the brushes and the curved one will touch more segments than a square ended one and presumably give more torque! If i rotate the starter by hand its then fine but it then happens again.

 

[Paul Marx]

Clicking is the solenoid yes not the starter but starter not rotating is the issue. I am convinced its due to the ends of the brushes and the curved one will touch more segments than a square ended one and presumably give more torque! If i rotate the starter by hand its then fine but it then happens again.

File the end of the brushes to suit.
End of problem.
Paul

 

[Zacgrief]

File the end of the brushes to suit.
End of problem.
Paul

Yes i know but i would like to know if this is the cause first.

 

[Ventodue]

Clicking is the solenoid yes not the starter but starter not rotating is the issue. I am convinced its due to the ends of the brushes and the curved one will touch more segments than a square ended one and presumably give more torque! If i rotate the starter by hand its then fine but it then happens again.

OK.

You may be right, but please understand that these bikes are renowned for their difficulty in turning over. The cause is normally put down, not to what you suggest, but rather to an unfortunate combination of high compression, unsympathetic valve timing, undersized electrical components, and faulty gearing ....

So, first things first. With apologies if you know all this already, have you:
1. Upgraded the starter cables to the chunkiest possible?
2. Upgraded the solenoid to a more robust version that the OEM Hitachi unit?
3. Fitted the battery with the most CCA you can find? 220 is about the minimum. Is it in good condition?

And finally, what is your starting technique? Do you put the bike in gear and then roll it back against compression before jabbing the starter button? (Do not hold the button down. Jab it and release. Holding it down just heats up the starter and drains the battery to no benefit).

If the answer to all this is 'Yes', then I agree it would be appropriate to look at the starter motor itself. Obviously the commutator needs to be clean and the brushes making as full contact as possible. To achieve this latter, if the Beemer ones don't work, you may have to fashion up your own brushes out of blanks. Old school auto electricians normally have a selection.

You can try a 4 brush conversion using Honda parts. Theoretically this promises much, but for me the result did not leave up to expectations.

If all this fails, the final solution is to do what Laverda themselves did, albeit very belatedly; change the gearing ratio between the starter and the crankshaft. Those who have done it say it works (in combination with the other stuff above, nat' ).

However, I am led to believe that the gear sets to do this are no longer available. But check with 3CMoto.

 

[Zacgrief]

OK.

You may be right, but please understand that these bikes are renowned for their difficulty in turning over. The cause is normally put down, not to what you suggest, but rather to an unfortunate combination of high compression, unsympathetic valve timing, undersized electrical components, and faulty gearing ....

So, first things first. With apologies if you know all this already, have you:
1. Upgraded the starter cables to the chunkiest possible?
2. Upgraded the solenoid to a more robust version that the OEM Hitachi unit?
3. Fitted the battery with the most CCA you can find? 220 is about the minimum. Is it in good condition?

And finally, what is your starting technique? Do you put the bike in gear and then roll it back against compression before jabbing the starter button? (Do not hold the button down. Jab it and release. Holding it down just heats up the starter and drains the battery to no benefit).

If the answer to all this is 'Yes', then I agree it would be appropriate to look at the starter motor itself. Obviously the commutator needs to be clean and the brushes making as full contact as possible. To achieve this latter, if the Beemer ones don't work, you may have to fashion up your own brushes out of blanks. Old school auto electricians normally have a selection.

You can try a 4 brush conversion using Honda parts. Theoretically this promises much, but for me the result did not leave up to expectations.

If all this fails, the final solution is to do what Laverda themselves did, albeit very belatedly; change the gearing ratio between the starter and the crankshaft. Those who have done it say it works (in combination with the other stuff above, nat' ).

However, I am led to believe that the gear sets to do this are no longer available. But check with 3CMoto.

Thanks and yes i have done all that and the starting is worse than before. I actually think there was nothing wrong in the first place apart from me not knowing how bad the standard starting circuit is.

The only item different now is the brush faces hence asking and it appears from this thread someone else has the same issues when using BM brushes in the laverda starter.

 

[Andy]

Regarding brushes generally, these can be shaped to suit with sandpaper etc. Introducing a curve at the end is nice but will happen anyway with wear. Contact is only through one pair of opposite segments at a time. When installing new brushes they can take a little time to bed in regardless of a pre-made curve, professionals will usually apply a little abrasive “comm chalk” to help make the best possible contact.
More important is to ensure that the brushes fit nicely in the holders so they slide easily without being loose, and the springs are able to hold the brushes straight and firmly onto the commutator. Brush holders should be clean and dry and fixed firmly.

If the starter works sometimes but not always (perhaps you need to rock the bike in gear) and lacks power then I would check the commutator carefully for any signs of a dead pole, is any segment showing more wear, arcing, or colour change. If you find one then you may also notice similar signs on the opposite segment. Also the old brushes may show arcing and chipping on the trailing edges.
If it looks ok then clean the commutator with sandpaper before reassembling and running it on the bench. It should sound fairly quiet and run fast and smooth. If it sounds like a small arc welder then it’s probably time for specialist help and maybe a new motor.
There are several other tests that can help but also require specialist knowledge and tools.

Please note I’m not a zane expert, I’ve just fixed a few electric motors

 

[Vince]

A test I saw the very experienced Auto electrician do to my 3c stater motor after he rebuilt it was to hold its drive gear against a soft pine heavy piece of timber and energise it causing it to rub and cut into that timber like a router. That proves it produces strong power and does stall under load. Looks dangerous as hell and surprised me at the time.