PMA and ignition question!!

[jkr277]

I'm thinking on making the investment on a PMA. Most likely a kit from Hughes Hand Built, along with a capacitor in place of the battery. Kick start only...
Will I be ok with factory ignition with the capacitor and what not?

 

[jonboy-xsbobber]

I think you can use your points ignition but if you have the newer style ignition you will need to go to points or something like a pamco someone correct me if I'm wrong

 

[jkr277]

Ok cool thanks. It's stock 1977 set up with two coils.

 

[jonboy-xsbobber]

You might want to get a second opinion I'm by no means a expert on this

 

[jkr277]

I will, thanks for the input though!

 

[XSLeo]

Yes, you can run points with a PMA.
On the 80 up TCI ignitions, it uses a magnet in the alternator rotor to trigger the pick ups mounted on the stator.
To install the PMA you remove the stock stator and rotor. This removes the magnet and pick ups. With out these parts the TCI doesn't work.
No matter what ignition you use, use a key to lock the PMA flywheel to the crank. Then properly mark the TDC, idle and full advance marks. This way when you replace the points you will have timing marks to do the job with.
With out a key the PMA flywheel can slip on the crank and any marks you make will be wrong the next time you want them.
Leo

 

[wherearewe]

Yes, you can run points with a PMA.
On the 80 up TCI ignitions, it uses a magnet in the alternator rotor to trigger the pick ups mounted on the stator.
To install the PMA you remove the stock stator and rotor. This removes the magnet and pick ups. With out these parts the TCI doesn't work.
No matter what ignition you use, use a key to lock the PMA flywheel to the crank. Then properly mark the TDC, idle and full advance marks. This way when you replace the points you will have timing marks to do the job with.
With out a key the PMA flywheel can slip on the crank and any marks you make will be wrong the next time you want them.
Leo

Hughs current kit specifically says do NOT use a woodruff key. I emailed him about this and asked. He replied the taper on the flywheel locks it into place. If i recall there is no groove cut into the flywheel for a woodruff key anymore. I guess if you want to modify it and use a key it won't hurt, but i assume he has tested it and found if properly seated and torqued it won't move. Just thought you might like to know that Leo.

Switching to a pamco is a good idea too. Reliablity is much improved and it draws a very small amount of current which is a plus on no battery systems. Well worth the money.

 

[jkr277]

Awesome thanks for the help!!

 

[650Skull]

A link to PMA problems and solutions.

As for the taper on some PMA rotors read the posts by Mrriggs. A key would make sure there is no slipping, Hugh is not fallible.

 

[wherearewe]

Well no of course not, no one is infallible. I'm just saying that on his install instructions for his product he says do not use a key. The rotor will not fit the stock key so further modification or a custom key would be required. Until very recently you would be hard pressed to find too many on here with a bad word to say about him or his products...

 

[retiredgentleman]

Yamaha has always used a woodruff key to lock the rotary position of its alternator rotors. Why do you think they do that? Think about it...................a heavy rotating mass spinning at various rpms on an engine that vibrates.

 

[wherearewe]

Yamaha has always used a woodruff key to lock the rotary position of its alternator rotors. Why do you think they do that? Think about it...................a heavy rotating mass spinning at various rpms on an engine that vibrates.

You're right, a key would stop it moving 100% for sure. But he makes it not me! Ask him to explain his decision to switch to a rotor that doesn't fit the key! His early kits did use one.

 

[650Skull]

Until very recently you would be hard pressed to find too many on here with a bad word to say about him or his products...

If you read the link and posts i mentioned it delves into problems with the taper and PMA rotors mismatching. The thread also mentions problems with stators that Hugh supplies, and he address's the problem at the end of the thread.

Hugh has made a good business out of the XS650 community. He also makes blanket statements, that is believed and passed on as truth by his followers, they are misleading and untrue. When someone claims to have spent time researching and years developing a new product, (as claimed), then they should be a new product and not a copy or slight modification of an existing one being sold by his competitors.

Given this I also applaud his give it a go attitude and his success.

Also i do not have to adhere to the hype of Hughs followers, when there is clearly misrepresentation of truth and craftsmanship.

 

[chizler62]

Yup! Agreed.
The amount of interference requirement would be different on a townie daily driver and a drag bike (think horsepower and then stopping it quickly) weight of mag, temp of assy, temp of crank vs temp of mag etc....so you have to calculate the interface needed between the crank and the mag and find the spec or parameter. Then you'd have to mark the starting and stopping spots on the crank and press the mag on.
But, since you tighten the mag on with a bolt. Well IT JUST DON'T WORK!
Ton more into it, but agree with the fella's post above....whats that old line from everyone's favorite movie?................

"if you want me to dump in a box and mark it guaranteed, I will. But, for you customers sake and for you sake, buy a quality product from me"