Hi everyone, New to the forum, and relatively new Triumph owner (2016 900cc Street Twin). When cold the bike starts up instantly on the button, revs slightly higher briefly then falls back down to a normal idle level. It will idle like this indefinitely. I would say I am leaving the bike to idle from startup for 1-2 minutes before riding off. I'm told my bike comes off the higher cold revs quite fast it seems. On my old bike (250cc) I didn't wait at all before I could ride it. When riding off things seem OK if slightly sluggish on the throttle, but often and especially when very cold like today, the bike will bog down (no power, dropping revs, pops, bangs, might even cut out on throttle) really badly and will completely cut out if I come to an idle stop. If it dies (usually mid traffic) then it becomes difficult to start again and I usually have to try 2 or 3 times before it will. This then repeats at the next set of traffic lights. If I rev the engine I can keep it alive, but the rev is very, very inconsistent and jumps up and down the rev range sputtering and popping, as if it's ignoring throttle position. Of course it's very embarrassing to be sat in traffic either revving erratically like a lunatic or having my bike cut out and blocking the road. I really don't know what to do, I'm not a mechanic and I haven't really got enough skill to fix it myself. I'm hoping for advice on what I can go to the garage with to ask for a fix? I have read that this might just be a "feature" of larger capacity engines and I should let it idle for a lot longer, though that's not too practical for me. Maybe I just don't have the right bike for my needs? Thank you!
Sounds like the bike's air temperature sensor is fault. They are usually in the air intake or airbox.
I don't know where you've read of cold stalling, popping, banging and difficult restarting being a "feature" of large capacity engines. That's a load of crap. My Street Scrambler, with a similar engine, behaves perfectly from cold start with maybe a 2-3 minute warmup, the time it takes me to kit up with jacket, helmet and gloves. The revs start high, gradually come down, then usually drop more with a quick blip of the throttle before riding off. Back in the carb days I'b be checking air and fuel jets but with modern ECU control it could be a sensor fault so you really need a diagnostic check. Also check for leaks in the exhaust and air intake.
Thanks for your reply. By "feature" I've mostly been told that larger engines just struggle more in the cold and need warming up first. I have been letting it idle but am I just not doing it long enough and that's the whole problem? That would link up with what the garage said when they returned it to me with no faults found.
I would not pay much attention to what the garage told you as it sounds like you are being fobbed off. I would be more inclined to get a second opinion from another mechanic. See if you can find a trusted or recommended workshop in your area and let them take a look.
I have been leaving the bike to run for around 2mins now before setting off and the issue doesn't seem to be happening, despite it still being really cold. Is it still likely I have an issue or do you really just have to let them warm up a bit?
You should absolutely be able to run it from cold so if you do still have these symptoms they need addressing. Whereabouts in the UK are you, I'm sure someone will be able to recommend somewhere to take it
Old Post, I know. Had the same thing, turned out to be a blocked fuel filter. Very cheap fix. New to the forum, and relatively new Triumph owner (2016 900cc Street Twin). Love the bike but I am having some serious problems that I can't seem to get help with - have taken it to mechanics but end up just having it be returned to me with a "seems fine". I'll do my best to explain the issue. When cold the bike starts up instantly on the button, revs slightly higher briefly then falls back down to a normal idle level. It will idle like this indefinitely. I would say I am leaving the bike to idle from startup for 1-2 minutes before riding off. I'm told my bike comes off the higher cold revs quite fast it seems. On my old bike (250cc) I didn't wait at all before I could ride it. When riding off things seem OK if slightly sluggish on the throttle, but often and especially when very cold like today, the bike will bog down (no power, dropping revs, pops, bangs, might even cut out on throttle) really badly and will completely cut out if I come to an idle stop. If it dies (usually mid traffic) then it becomes difficult to start again and I usually have to try 2 or 3 times before it will. This then repeats at the next set of traffic lights. If I rev the engine I can keep it alive, but the rev is very, very inconsistent and jumps up and down the rev range sputtering and popping, as if it's ignoring throttle position. Of course it's very embarrassing to be sat in traffic either revving erratically like a lunatic or having my bike cut out and blocking the road. I really don't know what to do, I'm not a mechanic and I haven't really got enough skill to fix it myself. I'm hoping for advice on what I can go to the garage with to ask for a fix? I have read that this might just be a "feature" of larger capacity engines and I should let it idle for a lot longer, though that's not too practical for me. Maybe I just don't have the right bike for my needs? Thank you![/QUOTE]
