I'm reluctant to add to this, as so many far more experienced folks have already added their considerable wisdom to this discussion.
Instead I'll recount what happened to me when I had a similar problem after replacing a head gasket on a B33. Frustrated and disgusted with the engine's inability to cough to life I decided to have a think. While doing that "thinking" I elected to change the oil to a winter blend as the autumn was definitely making itself felt. At the time everyone was advising me to use 20/50. So I did. Result? The cold engine spun just a shade faster and immediately sprang to life.
And one from very left field.
A motorcycle shop contacted me because he was having problems with a customers B33.
It would work in the shop but a week latter in the customers home it was a no go.
He would bring it in the mechanic would clean out the carb double check everything the bike would start & run just fine.
The mechanic refitted the tank & filled the tank with fresh fuel.
Took the bike for a test run, then dropped it back to the customer.
Next weekend the customer could not start it.
THis went on for months till just for the heck of it he tipped out the petrol & put it into a known good engine.
That one would not start either.
What was happening was over the week the volatile elements in the local slop we call fuel was reacting with the tank liner resulting in fuel that would not ignite at room temperature.
A new tank was fitted & the bike has been running like a top for the past 11 years.
['Instead I'll recount what happened to me when I had a similar problem after replacing a head gasket on a B33...']
Good point about the oil, a 'wet sumped' engine can also be a pig to get started due to oil drag on the crank...
Regarding the extract from your posting...The B33 shouldn't have a head gasket..The head is lapped to the barrel spigot like a valve. Not having a head gasket is one of the major plusses of the B33 I've always thought!...Ian
Thanks all for the latest replies, fresh petrol is the next thing on my list, I did reseal my rusty petrol tank, but at moment the bike is hooked up to one of those small portable plastic tanks suspended above the bike,being purpose made for the task the plastic should be good...maybe? The oil grade is interesting, i'm using a mono grade sae 30, wet sumping is always a problem, i fitted a drain bolt to the sump and usually drain it before kicking over. I'm investing in a compression tester as i think that needs looking at as i think I've tried most things!
You are right, of course, Ian. It was a long time ago and my memory is not always at its best when thinking of bikes I now no longer own. I had the B33's head off (for valves) and so I made the mistake of thinking there was a head gasket in the process.
No need to apologise...I frequently can't remember what I did yesterday, or what I have to do tomorrow....As for today, getting the day of the week right and remembering where I've put everything is the challenge...:laughing: ....Ian