Wildguzzi.com
General Category => General Discussion => Topic started by: Michael_A on June 30, 2026, 05:52:04 AM
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Hi All,
This is NOT a question on how to bypass the evap system in the above referenced bike, but rather what are the expected improvements one could expect?
On mine, I've noticed irregular idle when hot in traffic; very low speed throttle response is at times "twitchy"; and hot starting seems to sometimes involve longer cranking.
I'm familiar with how the system is SUPPOSED to work, but at the end of the day it's really creating a vacuum leak with an opportunity for an over rich mixture. Sometimes. Never mind the issues of potentially creating a pressure differential (to atmosphere) within the fuel tank.
So I did the bypass (blocking the line between the valve and intake manifold) and inerted the tip over valve (tank basically venting to atmosphere via the carbon can), runs and idles fine in the shop, but won't get a chance to get it out for a few weeks (traveling).
Are these the expected symptoms one can expect to have cleared up?
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Obviously you think so right because that's why you tried it, no?
But you don't think the engineers considered the "potential vacuum leak" or "pressure differential" when they designed the bike?
Well, let's wait and see if any of your troubles return and, if they do, then you'll know.
And if they never do, then you'll know.
The one and only time I eliminated the system (Jackal) I later found my garage smelling like gas in warmer weather. I would also think you should be more careful not to overfill the tank now.
I'll be interested to see if it solves your problems.
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very low speed throttle response is at times "twitchy"
This is 100% why I did the mod on my V7 850 (2023). At low throttle angles, the engine would not respond at all, then with a bit more throttle the bike would lurch forward. It was basically impossible to ride smoothly at slow in-town traffic speeds. Properly removing the EVAP system was a 100% instant fix, for $0. Other people don't report any such problems with the stock system, so it could be that it varies bike to bike.
I think you are going to want to remove or at least disconnect the EVAP can, or it will get saturated with fuel. Just let the tank vent line hang loose under the bike, like on every motorcycle ever made up until some time in the early 2000s.
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I deleted the whole system on my '26 Special. I it improved low speed running on mine substantially. It does like to be warmed up for a few minutes before riding off. I let it run while putting my gear on. The only jerking I get is from not holding the throttle steady, which I believe is from ride by wire throttle. Not enough resistance to keep from being steady with and the responsiveness of the engine. I have taken to holding either the bar end weight or the switch housing with the grip to steady my hand.
kk
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I bypassed mine a couple of months ago hoping for improved low speed tractability; it made no difference so I un-bypassed it. I then installed a "Rapid Bike Fueler" in hopes it would do what I wanted and it made a huge improvement. I'd like to try an upMap just out of curiosity to see if it can be even better - you know, as good as carbureted motorcycles were! ;)
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Bypass AND Upmap on my Stone Ten - HUGE improvement!
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Update on my evap bypass; Low speed running is MUCH improved, as is hot starting and idle quality. Drive-ability in traffic (stop and go, very low speed) is dramatically different and improved. Just pulling away from stoplights feels much easier and low speed response and throttle modulation is definitely improved. Yeah, I may smell gas in the garage SOMETIMES, but no worse than any other old school bike with carbs. No downside that has revealed itself yet. I may pull the canister and "clean things up" under there in the near future, as things stand now they are fully reversible should this experiment not work, but so far it has yielded a marked improvement.