Can't get my 75 commando to run again

Hey Guys,
I have been fooling with my 75 Commando project all summer trying to figure out all the ins and outs of Nortons. I am a newbie. I rebuilt or replaced all the switches and brake parts. I replaced the ignition with a Pazon, and replaced the cards with the upgraded amels. I had it running for a while this summer, putting around here and there figuring out what the next project will be on this bike. It started being harder to start and then started running on one cylinder. Now I can not get it to start at all. I set the valve clearances. Reset the ignition. Pulled the carbs and looked for dirt. Cleaned grounds. I did a compression test and it read about 160 per cylinder. It has spark and only will sputter after first tickle. I gave it a shot of starter fluid and it fires but does not run but a few revolutions. Sounds like it is not getting fuel but it tickles right up.
What am I missing?
Thanks, Scott

Is the gas that is in the tank fresh? If not sure, drain the bowls and get a gallon of fresh.
Are those carbs REALLY clean? Every orifice, nook and cranny?
Is the initial static timing on the Pazon correct?
Do you have spark on both cylinders? If only one, swap the leads to the opposite side and see if the issue stays with the coil or moves with the lead.

Check the fuel flow from the tank. When you tickle it, how long does it take for gas to flow from "both" ticklers. Check your needles and clips. Check pedcock and banjo strainers for funk.

One carb not functioning will mess up the whole program.

Sounds to me like the battery is going dead.

Something amiss in the charging system, or it doesn't get ridden long/fast enough to recharge the battery between rides.

Battery is new and on a trickle charger between attempts to start. I will drain whats left of the fuel and check petcocks for gunk, they were new but who knows what still might be floating around still in the tank. It does not take long to tickle up though, a couple of seconds. I do have spark to both plugs but I am thinking about running the pazon directly to the battery to see if that does anything.
Is there a separate ground that goes form frame to engine? I do not see one, maybe that is an issue?

Is there a separate ground that goes form frame to engine? I do not see one, maybe that is an issue?

Click to expand...

yes!

do it! don't question if necessry, do it anyway!
and just to make SURE, run a nice real thick gauge wire from the rear left motor mount down to the
oil filter and attach it to one of those securing bolts, after dremelling of chiseling off the black paint
so you get a good clean ground

I also run a ground wire from the positive battery terminal down to that oil filter to frame bolt.

Check your plugs
If they are fouled up with gunk it will not fire up, if there is no spark but you get a jolt holding and earthing the plugs thats the problem
Also check the earth wires from the coil to frame (if there is no current)
A corroded or faulty connection is all it takes to stop the fun

Good luck

I did get her running again. Lots of possibility for the cause. My best guess was a stuck float bowl. I dropped both bowls to check and clean and when the one on the bad cylinder was removed I think I heard it click like it settled into place. I did have a bunch of gunk on the petcock filters. I had a plug wire rubbing on the cylinder head mount that I insulated. I also ran an extra ground from the engine to the frame. Gonna take it out for a road test this morning as soon as the skies clear a little more.

Glad to hear you've got it sorted.
I've had similar issues in the past, and pretty much every time it was gunk in the pilot jets.
The old Amals are easy - just remove the mixture screw and prod the idle jet through with some brass wire - I found a plentiful source wrapped around some brands of red wine, so I just have to keep buying the stuff

I have no idea if you can do this with the new Premiers though?

Check your electrical system has on the handlebar (left or right) the switch with the off button entered!!!!

Check these out
http://www.ebay.com/sch/i.html?_nkw=12+ ... elay+relay
I do not like that handle bar switch either, mine seems a little shady. I took it apart and cleaned it well but don't trust it. With this relay you could run the ignition hot to the battery with out having to worry as much about an iffy kill switch.
By the way it ran pretty good this afternoon. May need to tweak the carbs a little but I'm happy. Took it to a small town car show a little north of me, it is kinda cool how much attention she draws.

I ran relay trigger through the key and the kill switch so they only needed to carry a trickle current to click relay power feed. Norton momentary kills are only good for rolling back fires and stopping at mail boxes so a real on/off easy to tag robust switch ain't a bad idea. Can save some switch terminals with the condition improver solutions like Detoxit [sp].