Setting up Pamco / VM34

[AllanCaveNZ]

Hi guys,

I've got a '79 xs650 special and just installed Pamco ignition with MikesXS dual output coil (black one not green one) and Mikuni VM34s from Michael Morse along with a new PMA. Problem is when I've gone to kick it over it revs realllly high straight away, weirdly enough it won't kick over if I only have the left carb choke on but will kick over if I have only the right carb choke on.

I didn't see any instructions on which output from the coil goes to which sparkplug but I've tried it both ways round (is there a correct order?) the throttle cable and slides seem fine, the advance springs have tension and snap back nicely, no obvious vacuum leaks, cleaned the spark plugs, tried the Pamco with timing retarded fully and it slowed down a little but not a lot, set it back to the middle after that tho.

Could I have installed the pamco incorrectly at all? It seemed very straight forward. The carbs should be set up reasonably enough to get started okay as came from 650central with vacuum barbs and jets adjusted, could I dial down the idle or air screw to see if it makes any difference?

Valve clearances set, cam chain tension checked etc.

Any advice appreciated, I'm away for a couple days but will try check from my phone. I'll put a pic of the bike up if no one abuses my use of massive firestones ; ) still a work in progress... I'm in Melbourne, Aus.

Thanks!
Allan

 

[DIRTY DOG]

turn down the idle screws a little to see is it helps no carb comes pre set and runs good right out of the box you will need to tune the carbs to your bike.

 

[AllanCaveNZ]

Thanks, yeah I will do that next, I had to turn the bike off quickly as was revving so high as soon as it started.

Just out of interest on dual output coils it doesn't matter which spark plug goes to which output on the coils? And the pamco should just be set in the centre of its adjustable area and tweaked as needed with a timing light once it's idling better?

 

[5twins]

Yes, it doesn't matter which plug lead connects to which plug. That coil fires them both at the same time. If the bike is starting then the timing must be close. Dial it in exactly with a timing light once you get the idle to come down. The high idle is probably just improperly set idle speed screws. But, make sure there is adequate slack in your throttle cables so they're not holding the slides open.

 

[gggGary]

+2 idle speed screws and throttle cable length. Also cable clearance, the VM/cable combo can get really tight/crimped under/behind the petcock. Getting the carbs rotated just right on the intakes helps with the clearance issues.

Sharp looking bike, those are some big ass tires, LOL

 

[AllanCaveNZ]

Thanks again all, feel a bit more sure of the order to do my trouble shooting in now.

And yup them are some big ass tyres ; ) kind of just a fun build as have a couple other bikes for going real fast through twisties won't be looking to push this one quite as hard. Shortening the rear behind the shock mounts by a few inches and and then some paint n polish once I'm happy with everything.

Happy new year all!