Yamaha Big Bear Starter issues.

[Thom592]

The 400Big Bear I'm working on, had a couple issues. Starter is spinning backwards.. What would cause this? 

The brushes are in place and I could find no burnt marks inside..

Any Insights would be greatly appreciated. 

[davefrombc]

It may be the brushes have been reversed, changing the polarity. Have you  had them  out and accidentally  switched them ( and their wiring) when  putting them  back? If  the starter was like that when you got the machine , you could try  switching them to see if that fixes  it.. I don't know of any other way  it would reverse.

 

[Gwbarm]

I have seen them internally short and start spinning backward, but it may be as dave said brush problem.

[gbrsk8]

How do you know the starter is spinning backwards? Generally pretty difficult to do that accidentally, but stranger things have happened.

[Mech]

As said it must be getting reversed voltage. Has the battery been out ? Has the starter been overhauled ?

If it's in the bike still I'd take it out and confirm it straight from a battery in case the battery has been installed backwards. If the battery is in backwards though it will almost certainly have blown the regulator. If the regulator is blown it will probably make sparks when the battery leads are connected.. I think.

[davefrombc]

Most starters run the same direction whether  they are wired straight or reversed.  There are motors built to be easily reversible  by shifting the position of the brushes on the commutator. Accidental shifting of brushes on a motor not designed for it could still cause it to reverse.

 

[Mech]

Only parallel fields motors always run the same direction. These are permanent magnet motors as far as I know which will run backwards with reversed voltage.  I also though it would be hard to get the brushes in backwards. Most have a solid power connection bolt coming out the side of the cover. I don't know how that could get misplaced..

I'm interested how it's come to be running backwards. Hopefully it has been apart. If not then the battery's in backwards.

[Caseknife]

Replaced a started drive in a Polaris Sportsman 500 once, then discovered that the owner had replaced the battery and hooked it up backwards, swapped the cables and it started right up.

[Mech]

Ok.. That's a good system then.  Often putting the battery in backwards plays havoc with the electronics..

 

[mga]

no follow up on this?