Modern Vespa

After a week and a half of unreliable operation, with symptoms identical to what everyone describes as Evaporation System failures, I decided to detatch the hose from the top of the carb which, essentially, disconnects the evap system.

I haven't done any other plugging or routing or venting. My two test rides yesterday (in 90 degree heat) went flawlessly: Smooth idle, good acceleration, no stuttering or dying.

What kind of consequences am I looking at for taking the easy way out?

TJH

Did you plug either the hose or the inlet?

You nailed it. That connection is the crux of the problem. And it will run fine with only that disconnection.

Conservative (vs full removal) further mods would be to plug the hose and attach a short (6") length of open ended hose to carb nipple.

Thanks! That's what I'll do.

Is the problem a clogged system / too much vacuum in the tank?

I did disconnect Evap on GT200 and decided to place a foam filter as a precautionary measure.

First was very simple, wrapping foam around plastic stem and affixing to carb.

Second (what's there right now) is a bit more involved. Picked up a foam filter disk, housing and then affixing to carb...which reminds me that I should either clean it or change it out.

Note: I cannot find the HPI housing anymore...so I opted to simply purchase similar filter material and replace as needed.

Most have opted to leave port open...without filter.

I did the same thing using a plastic pipe cap and lawn mower filter material. I clean it in kerosene periodically and there is always a bit of dirt in it. It oils itself.

Bill

Filter not needed: factory "Euro" carb hose elbow for evap disconnect