Ironhead !970 XLCH Wont start

[Iron75]

Hey everyone,

A buddy of mine bought a 1970 XLCH a while back and we are really struggling to get this thing on the road. Neither of us are experienced what so ever, so this all a very flustering learning experience to say the least...The bike has a mag on it with a super b. When he first had it it would sputter and pop when just going down his road now it won't even start. We recently tried to fire it up again and we watched the mag spark, made sure the timing was lined up and the points were the manual distance apart (.015in) and made sure the plugs had spark too. We put gas in it and it immediately flooded the back cylinder and started pouring out of the exhaust. So we fixed the float and what not but then we weren't getting any more spark out of the plugs or anything as well as the timing was all out of whack again in the mag. We are lost so any suggestions or tips are greatly appreciated!! I am a huge fan of this forum hopefully with everyones insight we can get it all figured out!

Thanks guys!!

[bustert]

sounds like it is a mag problem and from what you say, I would pull it out and check the drive. if the mag is slipping time, either the drive/driven gears are bad or the pin on the shaft is sheared. also, the capacitor could be bad and shorting out the electrics. if you can not dynamically test it, replace it. it can fail open, short or change of value and can pass a static test but will show bad under actual running conditions. in a mag, it is all about timing of the magnetic fields and if off, it will not produce a very good ignition if at all.

[Iron75]

Ok awesome!! Thank you so much! We actually replaced the pin last time we pulled the mag out so I guess that just leaves the gears and we will also try a new capacitor as well. We were also thinking that since he never changed the jets that were originally on the super b that might also be an issue when trying to get it to start up would that make sense or should it still start it just might run a little funny?

[Mosey]

The Super B is a little large for stock Sportys but will work. S&S has instructions online that will get you to baseline settings. The B is a stone simple carb. Have you had it apart and completely cleaned it? You didn't lose the little steel balls or the o-ring didya? So many details...

Start with the ignition and move on to the carb. One thing at a time.

[bustert]

before you pull the mag, check the shaft play, if the bushings are worn, the shaft will wobble and will screw with the points setting and it will mess up dwell. say if you set it at .015, it could wobble .005 either way or more.

[Iron75]

Sounds like a good start to me! Thank you very much! We haven't pulled the super b totally apart yet the only thing we really did to it was fix the float because it wasn't quite working right but I'll be sure to have him open it up and at least clean it up a little.