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[Simplo]

Hi all,
this is Simone from Italy. Firts of all, please, forgive my bad english, I hope it will be enough to explain my problem.
I own a Bullet 2007 350 STD, she never gave me any serious problem.
About a month ago I take her out of the garage, as usual, and tried to let her start.
Usually she gets running on firts o second attempt.
In about 56 attempts I tried every kind of combination: with choke, without choke, with throttle, without throttle... swearing, not serating: nothing to do.
Then I stardet standard checks: spark ok, valves ok, compression ok, sparkle ok...
It seems no fuel come from the carburettor.
"May be the float is locked" I tought.
Than I removed the carb, cleaned it at reinstalled.
At the first attempt the throttle cable broke.
Ok, let's change it! I removed the carb again, disassebmled it and changed the cable.
As I was reassembling it I saw the main needle does not fitted well in the hole, it was blended.
May be I put something on it when it was removed and blended it.
Ok, I connected to Hitchcock's shop and ordered a new one.
Finally the new needle arrived and I reassembled the carburator.
First attempt and OK! The bike started!
On the next day I used her for a 100km run: perfect!
Two weeks later I took the bike out of the garage again, tried to start and... nothing to do!
No way!
Other 77 attemps: with choke, without choke, with throttle, without throttle... swearing, not serating: nothing to do.
All checks ok!
Ok, I removed and disassembled the carb at least 10 times.
Cleaned it with air, all passages ok!
Tuned the float level and verified the main needle retainer is in the middle poisition.
The only thing I achieved is that the bike starts with choke and, after 7 seconds, idle regularly without choke (as it always been for 10 years) .
As soon as I turn the throttle the engine coughs and turns off.
It seems not enough fuel reaches the engine.
If the chocke is on the throttle seems to work almost normal.
I tried everything: change the float level, retune the mixture, move the needle plier to richen the mixture.. nothing at all.
I also straighten up the old needle and tryied it again... nothing!

Any idea?

Thank you for your patience reading all this...

[Graham43]

Did you replace the plug with a new one? All my start problems have been solved by replacing the plug. That is why I always carry a spare plug.

[PeteF]

Beat me to it Graham.
It could easily NOT be the plug but worth a try for a few quid.

[papasmurf]

Old fuel? Air filter dirty/falling apart? Air getting in somewhere it shouldn't?

[Simplo]

Hi all, thanks for the reply...
Plug is a brand new one and also the air filter.
Also tried with old ones.
I don't think I have air passages after the carb and before the engine... To detect air leaks I tried to start the engine without the air filter and (once it idles) covered the carb air intake whit my and... it shit down almost immediately.
I was thinking at some fault on the mixture screw... any idea to check it?

[papasmurf]

Have you removed the petrol pipe from the petrol tank to check if fuel is actually flowing freely?

[Adrian]

Papasmurf's idea to check the fuel pipe and the fuel tap is good, don't forget to check the air vent in the fuel tank cap too, in case it's blocked at all.



As your 350 Bullet is a late model, does it still have its Pulse Air Valve fitted? If so check the fitting into the carburettor flange and the exhaust pipe as a source of air leaks, or check the blanking plugs if the PAV has been removed.



A.

[Simplo]

Hi all, thanks again for the replies.
The fuel line is ok, the fuel flows as expecxted, I know beacuse the small carb's tank is full of gasoline and also because with the choke or at just idle the engine can run for hours..
Yes, mine Bullet has the PAV system. It seems ok, but how can I check or bypass it?
I just tried to close the little pipe that hangs downs the carb flange, but nothing changed...

[Mark M]

I'm not familiar with these carbs but is it possible to install the slide the wrong way round, ie with the cutaway facing the engine and not the airfilter side? I ask because a friend of mine once had the same symptoms on a Honda CG125 and I found that he'd done exactly this. The bike would start on the pilot circuit but drop dead if the throttle was opened.

REgards, Mark

[papasmurf]

Simplo, just because there is enough fuel flow at tickover does not mean there is enough fuel flow for faster speeds.

You really need to remove the pipe from the fuel tank to check for a part blockage.

At least that will find or eliminate a problem.