So... my Hyper does not like the heat. It starts when it’s really hot, but will not hold rpm and stalls. Can take from 2 to 5 attempts to get it going. Obviously trying to rev it myself doesn’t work because of the RDW throttle not responding. I stumbled across this thread but initially ignored it because I have a UK bike so wouldn’t have the canister. BUT during a coolant change I was squeezing the pipes to clear the air gaps and noticed the canister was there. I currently live in Las Vegas, hence the heat, and it’s my first summer with the bike here so I don’t have any history of the issue. Anyone also have a UK 939 with a canister? Because I’m a little confused, and think I might remove it just to see if it helps.
Having Google imaged UK 939’s I think perhaps the 939 must have the canister fitted no matter where it’s sold. Hope it’s still ok to remove it as mine is now not attached!
No idea about the UK cannister being a think but it wouldn't surprise me. I removed mine this year, but I never noticed any issues with starting hot aside from the starter not being as strong as it should be.
I used to have hot-start issues, especially after filling the tank. Haven't had a single issue after removing the carbon canister.
I have a HS 939 2016 . Since I remember, when hot it,s difficult to get it start . It takes 3/4 tries. What I do is push the throttle a little before starting the bike and that does it.
I got rid of the canisters two years ago, not a big difference but the bike looks better.
Other than that it's a great bike, 36,000 km no issues.
I finally took the bike to the shop for the Desmo service, new chain and sprockets, and minor things.
I got rid of the canisters two years ago, not a big difference but the bike looks better.
Other than that it's a great bike, 36,000 km no issues.
I finally took the bike to the shop for the Desmo service, new chain and sprockets, and minor things.
not sure the hot start issue is just the canister. it may be a combination of canister and the crappy starter that has heat soak issues. There is a thread on upgrading the starter in here somewhere. After taking off the canister, It still took me 2 or 3 tries to start when hot.
I have to say. I also do not have the cannister on on Australian model 821. Problem is only happening as someone else mentioned only when hot. Cold start is great. Does anyone know how the vapours are managed without the cannister?
Without a canister they vent to the air. Hard starting when hot on an 821 is more than likely indicating that your starter is weak which is a known issue. In some cases it'll just be awkward to start when warm and that is it, in others it can get worse and die entirely. There's a thread on here covering the fix (better starter unit).
Does anybody know if its ok to remove the air lines on the left side of the throttle bodies? This tutorial removes the two on the right. What function are the two on the left sides? Can I remove and plug with no ill effect?
Joined Oct 2020
76 Posts | 11+
Santa Rosa CA
Merrily on my way to dump the carbon canister. All hoses out except right side front behind radiator. There’s an electrical connection to a cylindrical (valve?) piece with hose fittings on both ends. One from rear cylinder port and one from the canister side, which I have already removed. What is it and what foul purpose does it pose. Not seen in the many hand dandy demos!
Joined Oct 2020
76 Posts | 11+
Santa Rosa CA
Joined Mar 2013
3K Posts | 161+
Naples, IT
Renny, sorry you're stuck. Dealer took mine off so take my advice with a grain of salt. I'll just say there aren't any commercial bypass plugs or anything to install so just disconnect, secure and fire it up. I think there might be some knowledge on the hoses and what to do with those, like plug or re-route, but never any discussion on sensors.
Joined Oct 2020
76 Posts | 11+
Santa Rosa CA
First, thanks again for the response. Yup, that’s what bit me! This device was coupled to the vertical cylinder hose then routed to a bracket above the T junction. Im not sure how this thing functions except that it’s in the canister circuit. The surprise electrical connector is my concern. Unplug and get error warning? Plug both ends and leave connected? Will proceed trying to plug it first.
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Joined Oct 2020
76 Posts | 11+
Santa Rosa CA
What year is your bike> Check this link - EVAP / Canister Removal kit PVE-080
Joined Oct 2020
76 Posts | 11+
Santa Rosa CA
I pulled the lines off that and left the power connected. No errors and the dealer didn't mention anything when they had it in for the 18k service.
Joined Oct 2020
76 Posts | 11+
Santa Rosa CA
Sorry to bring back an old thread.
My 2016 has a cover over the evap, which I cannot see how to unbolt:
There are no external fasteners.
How do I get this off so I can do the rest?
My 2016 has a cover over the evap, which I cannot see how to unbolt:
There are no external fasteners.
How do I get this off so I can do the rest?
