carb cleaned. still stalls.

[Nonapplicable90]

Hey all, cleaned the carb and it ran excellent for a day. The next day it started stalling,only at speed though never idle. I checked to see if it is a vacuum issue, opened the gas cap and started it. It started which i hear shouldn't happen, so where do i go from here?

 

[jetlee]

Tank vent is clogged.

 

[Nonapplicable90]

Any tutorials or diagrams on fixing the issue?
Thanks for your help man.

 

[jetlee]

It's the hose coming off the front of your tank. Take it off and clean it out by any means necessary.

 

[Nonapplicable90]

Sounds good, should I try and clean out the vent unit on the gas tank as well? Is the any particular method I should be aware of?
Thanks again, being new to small engines and mechanical trouble shooting this forum has been a huge help.

 

[jetlee]

Do the tube first, it's common that it gets pinched or mud-dobbers plug it up.

The rollover valve itself rarely sees issues, if ever. Most of those are owner-caused breaking from over-tightening.

 

[Nonapplicable90]

I put new hosing in running to the charcoal pack (3/16). Still bogs out after riding 45-50 mph for a few moments, attached some excess hose to the fuel vapor vent and blew through it. Seemed clear. Bike still starts with gas cap off.

Any other suggestions on progressing from here?

 

[Cosworth]

I think jetlee thought you ment the bike would ONLY start with the gas cap OFF. Are you staying the bike will start and run with the cap on or off?

The bike will start with the cap on or off doesnt matter, now if the vent was plugged and the cap was ON it wouldnt allow fuel to get to the carb.

 

[Nonapplicable90]

Oooh.. Sorry lack of knowledge on the topic. Yea it starts fine either way. Contemplating taking it to a shop but I feel like that's giving in

 

[Cosworth]

Does it only start missing after the bike has warmed up? And does it completely die or start chugging horribly?

If it only does it when warm it'd be worth checking the coil, plug wires, plugs etc..

Or could still have trash in the carb possibly, maybe a bad petcock?

 

[Nonapplicable90]

I believe it's after it's warmed up. It doesn't die out right, it starts chugging, I give it some gas and it sounds like it's trying to keep burning it. I have a video of it doing so if that interests anyone who may be so inclined to help.

 

[jetlee]

Cosworth was correct, I thought you meant it only starts with the cap off.

Have you tried cruising around with the cap popped or off? That would be the next step.

It could be either of a couple things. As Cosworth pointed out, if it only happens once the engine is warmed up, it's likely an ignition issue, especially if it just started doing it for no reason.

If it does it regardless of cold or warm, it's likely a fuel issue. Possible fuel issues:
1. Petcock could be partially clogged. Disconnect fuel line from carb and blow air backwards into the tank. This will dislodge anything, but will taste absolutely horrible.
2. Your fuel line from your petcock to the carb could be gummed up.
3. Improper float setting.
4. Partially clogged main jet or emulsion tube.

 

[Nonapplicable90]

Ok will do that, when cruising around it's the cap off what should I be looking or listening for?

 

[Cosworth]

Wether or not the bike dies.

The cap off will rule out a clogged tank vent. If the vents clogged the tank will be under vacuum and wont let enough fuel get to the carb.

 

[jetlee]

The cap off will rule out a clogged tank vent. If the vents clogged the tank will be under vacuum and wont let enough fuel get to the carb.

Yes.

The next step after that is blowing through the fuel line into the tank and then going for a ride. This would diagnose a clogged fuel line and/or fuel valve if the problem disappears.

 

[Nonapplicable90]

Ok sounds good. Got a game plan for tomorrow. It's so strange that it worked fine on the freeway for a day. I probably should have fully drained the gas tank and cleaned it out when i had out off the first time...

 

[Nonapplicable90]

So if anyone is still here,I rode around with the fuel cap popped and it doesn't stall anymore... Now for a thorough cleaning.

 

[jetlee]

Sounds like a clogged tank vent line, stuck rollover valve or something in the charcoal canister.

Pull that hose off and clean it out by any means necessary (that doesn't damage the rubber).

After re-attaching it, blow through it into the tank in case your rollover valve is stuck closed.

Remove the charcoal canister. Leave the tank vent hose open to atmosphere. Follow the hose from the canister to the carb, cut and plug the hose or remove it from the carb and put a rubber cap in its place.