classic motorcycle forum

That is a nice bike.
I'd swap for any of my Enfields (later), any day of the week.
But I'm also 10,000+ miles away ...

A dab of grease or 2 well applied to the carby spigot may help (briefly) with any air leaks.
Just to try. And is easily removed.

A wipeover with oil on the chromy bits (nickel ?) will help prevent any further corrosion.
Will need to be wiped well dry before any heat gets to it, or may smoke a bit ...

I'm wondering if you have any later carbs you can try on it ?
Or, once warm enough, if that choke lever would be needed at all ??

I have not ridden it yet as I cant keep it running for long enough to feel confident . I have not ridden any bike for more than 50 years ,the thought of pushing it any distance at 75 is no fun at all . Tickling does not seem to change anything apart from a puddle on the floor. The problem I am finding is the balance of the two levers against mag advance. On my old car static advance is 0 increasing to about 35 at 2k+ if I try to get the car to idle with full advance it wont. So I try to get the bike to ilde with starting advance say 10/15 btdc . I have looked into an induction leak ,but will try again ,the inlet duct is about 6in long to clear the dynamo. Geoff

Thanks for the sound advice fellas, The engine is in reasonable nick, the piston/rings are fairly worn ,but from memory it is out at +40 .I toyed with the idea of a rebore or resleeve BUT ive heard horror stories of old cast iron pots cracking as a result . Looking around there are not a lot of 1929  355 barrels about . The reason for the one month delay on this update was a buggered calf muscle from when I forgot to retard the mag on starting ,boy that hurt!! Cardan I just picked up on your earlier post about the main jet  .038  is 1mm as near as the main jet  fitted is unmarked  but I think less than 38thou  Geoff

Hi Geoff,

Yes T15MDY sounds good - 1 1/8" throttle valve, and presumably 1" choke. The T25 I mentioned would be too small...

The compression thing is weird.

Re the ignition timing: The bike might run with all manner of timings, but it will only run properly if the spark is set at something like 35-40 degrees (probably 3/8" or so) BTDC fully advanced. There's no need to experiment.

The valve timing sounds OK at 15/15.

But is the engine in good order? It should have good compression - hard to move over TDC with the ks lever when the throttle is open. Maybe it has a burned valve? Or worn-out valve guides? Or worn out cylinder/rings? Or no valve clearance? Or no oil?

The last one worries me. Not sure how the oiling system works on a 1929 Model 355 (still total loss? or is there a scavenge pump to put the oil back in the tank? By 1929 most bikes had gone dry sump) but hope you've got it sussed out. I'd say the most important part of recommissioning any bike is to make sure nothing bad has got inside (like a wasp nest), that the oil tank is drained, cleaned and filled with new oil, and that the oil pipes and pump are clean and functioning. No compression can be a symptom of a very dry motor; maybe try a squirt of oil down the plug hole and see if the compression comes back. If the motor is still total loss, there should be at least an eggcup of petrol in the crankcase anytime it is running. If it's dry sump, make sure the oil is returning to the oil tank is a steady stream within 10-20-30 sec of the engine starting.

Leon

I would be giving the ignition system a closer look. The old remark about so many fuel problems being ignition has a lot of truth.
You wrote earlier the bike has been off the road for 40 years, old electric equipment doesn’t age well. To me it is all suspect , magneto, HT lead, etc, etc. You also wrote you had set it to fire about tdc. I think that’s far too late. Somewhere about 3/8” at full advance is a better starting point.
Resurrecting an old beast can be a quite an exercise as you are finding out. But satisfying.