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You need to plug/cap off the black air vent on the carb and make sure the tube going to the canister is plugged/capped off if you want to run without the canister. Also need to run the hose from the bottom of the bowl down to the fitting at the swing arm. Should run fine if your carb and the boots are ok. The boots are the two rubber fittings that hook the carb to the engine and the other one from the air box. They sometimes get dry and crack or are the wrong ones for a particular carb.
 

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The gas tank on a California bike is vented into the charcoal canister.
The tank needs to vent or bike will suffer symptoms similar to those reported.
A clogged charcoal canister will not vent properly
A charcoal canister can get clogged when saturated with excess gasoline from overfilling the tank.

While I may have given wrong hose routing from late nite memory ( my apologizes, correct me if wrong) certainly in post # 16 the black plastic "AIR VENT" fitting is just visible behind the sintered fuel filter. Sure looks like OEM new style carb to me.
 

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A California charcoal canister can be removed and both lines in left open to atmosphere. Capping those lines will not let carb nor gas tank vent so bike will stall and fail after short operating periods.

Fitting on frame cross member in post #13 if clogged can also make bike misbehave, it may be deleted either permanently or temporarily for diagnostic purposes.
 

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Is the OEM California cap sealed? ( not vented ) If so, then plugging/capping off the tube under the tank and putting on a vented non-California gas cap should work for the venting problem.
I'll take a look at my old California cap and see if it is a sealed type of cap. I put on a standard non-California OEM cap.
 

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Discussion Starter #26
Thanks, there is 1 air vent on carb. PO had that vented straight down through swing arm. Hose was dangling next to the fuel bowl overflow hose. Neither of those 2 were connected to the fitting seen on post 13.
Is this new routing correct:

1) connect line from canister to the air vent. (Vent pivots so it can easily swing up to fit that line)
2) connect canister to tank vent
3) should anything connect to fitting show on post 13? The only additional hose is from the fuel bowl overflow. I’m concerned the file would not drain from that fitting due to the angle in it.

thanks
 

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Discussion Starter #27
Also, I think it is the sealed Cali fuel cap. Not sure how to tell exactly, but nothing looks vented on cap
 

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My experience has been that TW gas tank caps seem to be non-sealed due to passages within the lock cylinder. Enough of a poor seal to allow minor fume odors and some leakage if tank is overfilled yet not enough venting to permit sustained fuel delivery over extended engine operation.

Perhaps download the free Service Manual to more accurate hose routing information. The manual is invaluable IMHO.
 

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The lock cylinder on the California tank has a rubber o-ring on it, but Fred is correct in that it could let a small amount of fuel out and is not enough to vent the tank.

You connect the bowl overflow hose to the angled fitting by the swing arm. This is normal for Kommiefornia smog set up. Refer to part # 34 for Cal only connection to bottom of bowl.
California newer carb diagram.png
 

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The gas tank on a California bike is vented into the charcoal canister.
The tank needs to vent or bike will suffer symptoms similar to those reported.
A clogged charcoal canister will not vent properly
A charcoal canister can get clogged when saturated with excess gasoline from overfilling the tank.

While I may have given wrong hose routing from late nite memory ( my apologizes, correct me if wrong) certainly in post # 16 the black plastic "AIR VENT" fitting is just visible behind the sintered fuel filter. Sure looks like OEM new style carb to me.
You can tell it's a clone by the idle adjustment knob and that the throttle assembly doesn't quite line up with the adjuster because the clone assembly was switched out for the OEM one.
 

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Discussion Starter #31
thanks - going to try and route hoses properly and do a carb clean. Lets hope the all balls carb kit will work with the clone.

The airbox drain hose was full of oil/crude so im sure a good cleaning will be in order.
 

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My humble apologies on inaccurate hose routing info. My California model carbs both have the black "AIR VENT" line leading down to swing arm area. My charcoal canister vent lines connects to fittings on the carb body just above the idle stop screw. Will try to post photos.
 

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Discussion Starter #33
Mine doesn’t seem to have that additional vent yours does above idle stop screw... I hooked canister to black air vent that pivots. Guessing that won’t work...
 

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For smog control one ideally wants the carb and gas tank fumes trapped by the charcoal bed.
For simple engine operation one needs the tank and carb float chamber to see atmospheric pressure at all times via whatever hose routing can accomplish this venting. One can get creative, just don't block venting to tank nor float bowl chamber.
Simply submersing the end of the vent tube during a creek crossing will rapidly demonstrate the need for venting. Sort of like pissing on an electric fence teaches a lasting lesson so does pushing a stalled bike out of a river.
 
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