Hesitant starter

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Mar 19, 2005
Not Commando but Atlas. My dilema. Just finished a Atlas Cafe Racer.
with Boyer Mk3, Tympanium reg/rect, RGM single Carb Manifold and brand new Amal930 with chrome slide.
I dont have insulators on the manifold/carb/head setup.
To start it ,I have to dose it up with a can of easy start. after that it will start and run great as long as I restart it every 10 minutes or so, if I leave it sit for an hour theres no way its going to start without the magic spray. Any thoughts, its quite frustrating and my leg is getting tired.
Don, Do you have a choke slide fitted? and also do you depress the tickler for starting? It sounds to me like you have insuficient fuel for starting, additionally if your idle circuit is blocked there may be insufficient fuel for starting with the throttle closed. Have you tried squirting fuel into the carb rather than EZ start? If you squirt fuel in and it still doesn't start I would check valve clearances to make sure that you are not getting insufficient opening or closing when cold, this is one dimension that does vary between hot and cold conditions. Lastly is the carburettor positioned parallel to the ground? If you used a commando manifold for example your float bowl could be at an angle and thus have the wrong float height. The EZ start might be giving you a false impression as we all know it will start almost anything. but if you have fuel, air and a spark at the right time it almost has to start eventually.
I.ve checked tappet clearances, idle circuit etc for blockages. I dont have the choke slide fitted. the carb is mounted vertical /horizontal. I,ve just noticed that if I hold the tickler down and blow in the fuel tank flodding the carb it started first go, so Its obviously lack of fuel . so I dont know if the float level is incorrect or whats wrong . its a brand new carb. not that that means much. I,m not sure that the tickler is actually pushing the float down far enough allowing it to flood . If I depress the tickler I dont seem to have any evidence of it flooding.
I tried to start it again ,No go, squirt a little fuel in there and away she goes. something wrong down low.
Don, It sounds like you are getting somewhere, The tickler should cause the fuel to squirt out the small vent hole when it is held down. If it is not doing so then either the tickler rod is not pushing the float down (it only has to push it lower than the fuel stop valve position) or the float level itself is incorrect. These are not easy to adjust with any accuracy basically you have to heat up the float bowl OFF THE CARB!!! and then tap the brass seat either in or out depending on what you want. If you were to turn the fuel on, leave it for a while and then turn it off again you can remove the float bowl carefully and see whether there is enough fuel in there. If you have a spare float bowl off one of your old carbs try that and see if it cures the problem. Good luck
don said:
I,m not sure that the tickler is actually pushing the float down far enough allowing it to flood . If I depress the tickler I dont seem to have any evidence of it flooding.

That would seem to be the problem then, how far does the tickler button move as just over 1/4" (6-7mm) would seem to be about right (read the advice given by RichardS in a previous discussion: http://accessnorton.com/norton/viewtopi ... ht=tickler?)
You should see fuel coming from the tickler after only a couple of seconds or so, if it is working properly?

Might be worth removing the float bowl to check everything (and that the float is actually clipped to the float needle)? Also check there is a good flow of fuel coming from the tank?

I wouldn't think it was a float height problem as you are overriding this when you operate the tickler?
Don,I fitted a single 32mm Amal to my 850 Commando,I got a warning from Les Emery at Norvil -- "you WILL need to use the choke (air slide) or she will never start".
I tried the bike without the choke, Les was correct, I wore out my leg trying to get the motor to fire up,I refitted the choke,couple of "tickles" and she fired on 2nd kick,even on moderately cool days 40deg. to 60deg. F I still need the choke,test everything else,i.e. float height,gas flow from tank to carb., etc., but I think that you will need to fit the air slide to have success.Ride safely. James
Thats very interesting James I,ll certainly try that. you would not think that would be needed once the motor was hot but it may be the case
Thanks for that,
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