Technical Dying with too much throttle

[nateelgrate]

Hello, quick question. First off im 19, grew up with fi, i have limited knowledge on carbs. Anyways, i have a 80 x1/9 which i picked up for $100. I got it running and idle-ing perfect. However, when i give it gas it dies out. I can slowly slowly give it gas up to about 4 grand, then put it to the floor and it revs up to redline quickly with no problem. To me it almost seems as if its getting too much gas? or does this sound like an Ignition problem? thanks a ton.

 

[sumplug]

Hello, quick question. First off im 19, grew up with fi, i have limited knowledge on carbs. Anyways, i have a 80 x1/9 which i picked up for $100. I got it running and idle-ing perfect. However, when i give it gas it dies out. I can slowly slowly give it gas up to about 4 grand, then put it to the floor and it revs up to redline quickly with no problem. To me it almost seems as if its getting too much gas? or does this sound like an Ignition problem? thanks a ton.

You have a carb problem. You may need a new needle valve that closes the fuel to float chamber when chamber full. Strip the carb down and give it an overhaul. Kits are available.

Andy.

 

[fastandfurryous]

This sounds suspiciously like the problem I've had with this carburettor in the past.

The jets are fed from a pair of drillings in the base of the carburettor, which run between the two venturi, and connect the two sides of the float chamber.

Dirt settles in here, and when it builds up, blocks the jets. The primary jet is always the first to block. Cleaning this area out is a major headache, as there's no easy way to do it. The best way I've found so far is to remove the jets, and blow through with compressed air.

You can do all this with the carb still on the engine.

 

[nateelgrate]

I don't know if its worth me messing with, i wish I knew more about carbs. Ill see what it takes, but i hear you really have to have your stuff together for a carb rehaul. I think ill buy a rebuilt one and skip the headache. yea im lazy, heck maybe ill give it a try. Thanks a ton for clearing that up though, huge headache.

 

[Sid]

:idea: Could be your accelerator pump....theres a spring loaded lever on the side of the carb operated by the throttle cable/cam, could be this has got stuck...abit of oil should free it off!!!
had problem with mine doing same trying to pull away from junctions.....

 

[jimbro1000]

The accelerator pump failing would give slightly different behaviour. The weber carb will always give enough fuel to keep the mixture within tolerance so the engine wouldn't try to "die" under heavy throttle, it just wouldn't pull very hard initially. The fact that opening the throttle wide enough to get the second throttle plate open "fixes" the problem points back at the original diagnosis.

The only real solution is to get the carb cleaned up and the jets cleared out.

 

[nateelgrate]

anyone got a good clean carb they wanna get rid of? Thanks

 

[nateelgrate]

I meant sell, not give away, just in case some of you dont understand my lingo.

 

[Rampage94]

it's not that hard to rebuild a carb mate, it's mince. all you need is a good set of instructions, the tools needed, and patience.

 

[nateelgrate]

This sounds suspiciously like the problem I've had with this carburettor in the past.

The jets are fed from a pair of drillings in the base of the carburettor, which run between the two venturi, and connect the two sides of the float chamber.

Dirt settles in here, and when it builds up, blocks the jets. The primary jet is always the first to block. Cleaning this area out is a major headache, as there's no easy way to do it. The best way I've found so far is to remove the jets, and blow through with compressed air.

You can do all this with the carb still on the engine.

Ill see if I can figure this out, I guess Ill just tried to rebuild it ..... AGHHH!