Modern Vespa

A brief recap of the situation.

Several weeks ago, I hopped on my '20 GTS300 HPE in anticipation of an early December ride fifty miles through the Black Hills 'up' to Deadwood for my coffee and muffin (orange/cranberry).

While riding to the gas station two and a half miles up the road so that I could spill overflow gasoline all over the general fuel tank neck area, the engine started to, as they say, 'bog' on applying full throttle and refused to run at anything over about 40-45 mph.

The bike has been doing this for some time, but never as severely as it was now.

Disappointed, I hobbled back home and parked the GTS until yesterday.

I was hoping that the problem had something to do with the ASR system, which would have been the least problematic of all the things it could have been. In an earlier thread I had posted here concerning my...concern, the ASR system was mentioned by several as a possible cause, so I found a video on resetting the ASR (I can't find my owner's manual, of course).

So yesterday, in our glorious late December 54 degree weather (F), I tried to get the ASR right with the world, but couldn't get the flashing 'ASR' words on the dash(?) to go solid from the blinking on and off part.

I did, however, get the ASR indicator to go off entirely, and the GTS ran perfectly for the short five mile ride over the same route that it had had problems with several weeks ago. It ran at full throttle up a slight grade just fine, and would accelerate to, and run at, an indicated 72 mph.

Apparently, the ASR system defaults back to 'on' every time the GTS is started anew, but I will turn it off again today and try to ride it for a longer distance and see if my possible good luck with it will continue.

Believe me, I DO hope that the fix is truly as simple as this may be, because I have no desire to haul this bike 400 miles to have a real Vespa mechanic diagnose it's problem. If I did have to haul it that far (in the spring) and at that expense, my temptation to leave it there might get the better of me.

I am also pleased to report that I got my old Honda CB900C running yesterday as well, seems all it needed was a new battery.....and (blush), gasoline.

I'll report back my findings this afternoon.

Not to discount your experience and apparent success, but I think adding a tee into the evap system that a person could open in times like this while it just sits.
To actually evaporate ahead of the charcoal canister. It's a flawed system because it cannot overcome basic human stupidity, first in the knee jerk design and handwringing trying to keep every molecule of fuel from hitting the climate triggering antennas. And secondly humans who don't read and apply what the manufacturers tell them to do.
None of the previous should be taken personally, for it's not intended in any way.
I've been harping about mass production of complicated designs for simple people for a long time. Like my sister told me one time, Veloce were just gas and oil people. Meaning they treat their horse n buggy like a shovel and wheelbarrow.
But they don't live in a cold area like you do.
I once ruined the same engine twice in a two week period, because of my environmental fears. I was using waste paint thinner in my gas tank with good success, until it didn't. Different type of thinner. Fond memories.
If you read this far, you get a cookie.
If you don't reply to it, we're microwaving it for you.
End thread derails now!

Thanks! I'll pass this on to my engine tech and see if she can find some time to look into the GTS's evap system and perhaps make some...umm...changes, but she's been pretty busy lately trying to sort out my Citroen 2CV.

I know it's a day early, but happy Christmas (Christivus?)...and where's my cookie?

Download your manual here https://manuals.vespa.com/

The ASR light is a warning light so light off equals ASR enabled. And yes it will reenable each time your turn on the ignition.

Lastly did you check and correct your tire pressure *before* doing the ASR calib attempt? This is important as changes in pressure affect ASR calibration and operation.

I checked the tire pressure a couple weeks ago, but not lately.

I disabled the ASR for the ride and the bike ran flawlessly, with not a hint of engine bogging during WFO acceleration or pulling the uphill grades.

I think that I can reasonably assume that the GTS's problem was directly related to the ASR system, so I'll just disable it every time I ride it.

I took the GTS out on a 32 mile ride this afternoon on rural two lane highways that included three uphill sections that were from 6-10% grades and none less than about a half mile in length.