Bike only runs on full choke, twist the throttle, she dies?

Buggar!

Was taking my ex. cop 1984 XJ750P to a charity fund raising meet with some fellow emergency vehicle owners. http://nzevc.yolasite.com/

No problems at all on the ride over from home (a little over an hour) but got stopped at some road works just short of my destination and I see a puff of light coloured smoke sail past me.

WTF! It's coming from my bike, no problems with her running at that stage though.

Got to the charity run and all good, show' n shine etc. but when the parade starts she won't start unless on full choke and pumps out loads of light coloured smoke.

Managed to limp to a family members house on full choke only because as soon as I twist the throttle the engine dies.

Checked the usual, fuel filter appears OK, still plenty of oil in the engine, carby boots all look good with no cracks etc.

Had been for a run only the previous week with no problems.

I was a bit energetic on the corners on the trip over so could I have stirred up some crap in the tank? (I would have thought the filter would have caught it though.)

Has anyone else had this problem?

Cheers!

 

never had the smoke problem. but only running with choke and dieing with throttle would indicate very lean mixture. not getting enough gas.

others have had problems that turned out to be the gas cap not ventilating and allowing fuel to drain from the tank. vacuum is occuring. try running without the gas cap and seee what happens.

other solutions would be plugged fuel filter. plugged fuel switch. floats too lean in the carbs but obviously you didn't do any carb work. the float seats have screens too that might be plugged up if you still have the screens in there.

i've seen instances where gas was just bought and now the vehicle runs like crap. sometimes a dryer chemical will absorb the water in the gas. like HEET for example. other times it just has to be run out. and problem goes away after fresh gas bought from another store.

had that problem on my V65 magna once. took 4 bottles of HEET just to run half way decent. once i ran out and bought gas again. problem solved.

bad gas is usualy more prone to winter though then summer.

 

Pull that Fuel Filter and do the "Blow-through-it" Test.
Even if it looks clean and new.

Looks for obvious Fuel Supply troubles.
Wanting to run on "Choke" indicated a Carb/Fuel/Supply fault.

See if it runs on PRIME.

 

Heya gents.

Yeah, I tried the tank cap test on the day but didn't see any improvement at the time, also tried her on the Prime setting but no joy either.

I'll try the blow through the filter test and maybe try some different petrol in her and see what happens.

Cheers!

 

Several things, old fuel, which is weird 'cause I went for a ride the previous week and then filled her up at the gas station before heading to the charity run, air screws slightly out and needed a seal in the fuel tap replacing so back on the road again!