starting problem

[Rocket Racer]

On most concentrics, opposite the pilot screw in the body is a plug. This can be carefully drilled out and tapped to I recall 2BA. this means you should then have clear line of sight to check the pilot jet is not blocked. Once cleared a 2BA screw can be loctited in to block the new hole.
Yes try another carb if its proven it is fine. But a humble pilot jet blockage can be enough to scupper starting and low speed running.
What plugs are you running? I've found that the new NGK's have inferior ceramic glaze and foul up real easy. If so try a pair of champions, they are less prone to fouling. A motor with fouled plugs is also a bugger to start.

Good luck.
Tim

[Tumbleweed]

 I get what you say Tim, I do have new ngk plugs , I might have a couple of old champions laying about somewhere , there is air passing thro the pilot jet hole I can see it when I put wd in the jet , but if its enough I don't know , I will see what happens when I fit plugs and  monobloc carb .    thanks  t w

[Rocket Racer]

Once you've worn yourself out trying to start it, immediately pull the plugs out and see if they are wet. If so then most likely an ignition issue (including the plugs).
Now while the pilot (jet, not the rider  ) will bugger up both starting and low speed running a decent tickle will flood the carb (bypassing the pilot circuit) and should start.
If the bike doesnt have an airfilter I always like to have a fire extinguisher handy (backfire + a flooded carb =bonfire  ) with an starting problems. (I accidentally burnt out a triumph decades ago when I was a uni student  luckily not a BSA but I still wasnt a happy lad afterwards)
But a primed carb wont keep a motor running and pilot blockage will typically stall it once the fuel prime has been burnt off.
A healthy ignition with a bit of fuel should bite, at least cough. Doesn't sound like yours is trying and ngk's wont help if your carbs not spot on.
If it does start, give it some berries so you can hear it run on the non pilot circuit range of the carb; once the needles lifted you will be getting fuel.

[Tumbleweed]

taking your advice Tim (sorry about the Triumph)   changed the plugs   the plugs aren't wet I was kicking it over and over , then it started I revved it a few times it even ticked over , then it stopped because the fuel ran out I think    then back to kicking I fires once each kick sometimes , ive even tried the other carb , I probed down the manifold just in case there was anything stuffed in there , now I am back to kicking , there is a good spark to the plugs all the time  and the timing is spot on it must be something stupid as it sounds good when it was running  ,         now her who shall be obeyed   is accusing me of being grumpy   and an old one at that , so something has got to happen soon ive ran out of ideas ,   t w

[RichardL]

Sorry I can't help more than has been offered by all. Sorry no one has been able to get to your place for the clanging together of heads. However, I did locate a picture of what you will look like after some time at the gym to balance out your left leg.

[chaterlea25]

Hi,
Try this



John

[kiwipom]

hi guys, I've heard that engines can get addicted to that stuff and wont start without it if you use to much, but good luck it does sound like a fuel problem, cheers

[Tumbleweed]

thanks for your time everybody, yes ive tried that " easystart"  but no response , I just wish the wife would take an interest in starting my bike she has got legs like that   ,    tw   

[Klaus]

Have you checked the valveclearence
Its only an idea.

[mikeb]

unlikely but: any change its leaking lots of air around ski-ramp/carb/manifold connection? like if the carb was over-tightened? spray some wd40 around the joint to see if it gets sucked in .
given it ran OK til the fuel ran out that's encouraging.

[Tumbleweed]

 yes the valve clearances are as the book and there are no leaks , ive got the points out now I fitted new ones I am not 100 percent sure where the insulating washers went , an exploded view of the set up would be handy just to be sure  but it wouldn't have run if that was the case ,    thanks chaps  t w

[Rocket Racer]

It does sound like a pilot circuit blockage. if you take the carb off and the pilot screw out, can you spray through (carb cleaner) the pilot intake hole and get flow out where the pilot screw has been removed. If yes then
If you put the pilot screw back in does the carb cleaner again sprayed in there come out the small drilling immediately in front of the slide (it should). These drillings are quite small and very susceptible to gum blockage! If they dont flow it wont go... 

Getting three of these carbs behaving the same on my triple drove me nuts    and is a common discussion point for the BSA group triple forum.
That was in the end why I had the forward drillings updated to the mk1.5 type  which involved removing the welch plugs but gets fuel to my engine on all three   

In your case as the concentric is not the original carb, it might be worth considering putting an original carb type on    or at least trying another carb?

If you like the carb you've got, I'd suggest you try finding someone who does ultrasonic cleaning

[a101960]

That was in the end why I had the forward drillings updated to the mk1.5 type

If I remember correctly was this not the reason that the MK 1.5 was introduced in the first place?

[Tumbleweed]

thanks for your input everybody its been very enlightening and useful of course , I am entering a spark plug tester to my toolbox I haven't had one of these befor it can show the spark while the engine is running or being kicked over , its arriving by post in a few days , I will keep you informed .   tim I tried another carb but still same    t w

[rocker21]

where in the UK are you?
might be able to help if you are not to far away.