sm13 spins wrong direction

[bored&stroked]

I bought a motorcycle sm13 [based on advice here] and swapped the rear cap with my old starter so it bolted up correctly. Starter is super strong, but its spinning in the wrong direction lol. I assume I can change that somehow internally?

 

[mthomps]

Polarity reversed somewhere?

 

[waxhead]

4 stroke starter motor

 

[WFO Speedracer]

Yes if it;s a motorcycle starter it pretty much would have to be.

 

[Jcary85]

I did some research on this a while back. iIRC it’s based on the fixed magnets in the case so can’t be switched easily. You can use the guts and put in a different case though.

 

[Quinc]

I did some research on this a while back. iIRC it’s based on the fixed magnets in the case so can’t be switched easily. You can use the guts and put in a different case though.

This is what I did.^

 

[Pro-pulsion]

Is it possible to just spin the barrel around and reassemble it backwards? I assume the magnetic poles are all grouped to be south on one side of the barrel and north on the other? Just thinking outside of the box

 

[bored&stroked]

I did some research on this a while back. iIRC it’s based on the fixed magnets in the case so can’t be switched easily. You can use the guts and put in a different case though.

I just so happen to have a extra oem 'maha case sitting around. Thanks!

 

[waxhead]

This is a classic one from using 4 stroke starters in 2 stroke skis

 

[WFO Speedracer]

I worked on a 74 Yamaha DT125 a few years back it had a combination DC generator -electric starter, they never worked that well.

I am also wondering why a 125 two stroke single needed an electric starter in the first place.

 

[bored&stroked]

So why do people on here talk about getting a moto sm13 and using it without issues if 4 stroke spin the wrong direction?

 

[WFO Speedracer]

So why do people on here talk about getting a moto sm13 and using it without issues if 4 stroke spin the wrong direction?

What guys are saying this ?

 

[Big Kahuna]

So why do people on here talk about getting a moto sm13 and using it without issues if 4 stroke spin the wrong direction?

I dont recall seeing this............

 

[WFO Speedracer]

I dont recall seeing this............

Me either which is why I asked , probably some Facebook advice.

 

[Sparkplug]

Nah I've posted on here that they work. I've never ran into that issue tho. Seems like bad luck lol.

What's weird. Is used a fat cat starter. And it worked fine on my ski???

Perhaps it matters if the starter uses a bendix vs engaging the flywheel directly? No idea. I bought a literal lot of sm13 starters. Like 25 of them. That were from various machines. And other than some requiring different shims. Never had one spin backwards? Lucky? Idk

 

[bored&stroked]

I've never ran into that issue tho. Seems like bad luck lol.

Story of my life lol

 

[WFO Speedracer]

I have run across this buying brush plates before, did the starter have any notes as to rotation, notations such as RH, LH ?

 

[Half flip95]

swap the current flow on the armature or the field... not both.

for the mechanically minded... cut the 2 wires that go to the brushes and solder in jumpers to make them go to the opposing side

 

[WFO Speedracer]

swap the current flow on the armature or the field... not both.

for the mechanically minded... cut the 2 wires that go to the brushes and solder in jumpers to make them go to the opposing side

This is what I was thinking, I can't see magnet location having anything to do with this , from my experience rotation is determined by brush location which is why the brush plates are marked LH and RH.

 

[Jcary85]

So why do people on here talk about getting a moto sm13 and using it without issues if 4 stroke spin the wrong direction?

I buy them all the time. Idk which ones went the wrong direction so it’s a bit of a krap shoot. Most recently I bought one for a CBR1100 and it spins the correct direction. I don’t think it’s so much a 4 stroke vs 2 stroke thing. Probably more about what side of the motor the starter is on but who knows