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Discussion Starter · #1 ·
I've noticed that my throttle cable gets stuck in winter sometimes. I don't remember the temperature when it happened last winter, but I've experienced it twice recently, and both times, the temps were around 20F.
I found a few threads (like this one), where people mentioned that switching on the heated grips caused this issue due to the grip expanding and sticking to the bar end. But my experience has been the opposite - after I idle for 2-3 mins (with the heated grips on), the cable starts moving again. But about 2-3 days ago, the temps dropped to almost 16F while I was on my way home, and the cable started sticking while I was riding. My current understanding is that the cold temps are causing the black cable sheath to shrink, and running the engine for a few mins warms it up enough to expand it again.

Anyone else experience a similar issue, and have any potential solutions for it? My bike does have 44k+ miles, so is it just an old cable and sheath? It's just a little bit annoying/disappointing, coz I'd have expected these bikes to be designed to operate at such temperatures.
 

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It'll be your grip being either caught on the bar end, or maybe even on the switch gear. The sheath is not so tight a minute shrinkage will not cause issues, let alone be fixed with a few minutes of radiant heat from the engine.

The only potential place i can think there might be some stiffness is in the end of the throttle grip, where the cables connect is in a plastic housing & the right angle tubes where it might need some lubrication.
 

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Discussion Starter · #3 ·
That's the weird thing - when the cable is "stuck", I can forcibly turn the throttle grip/actuator to open the throttle. It takes way more effort than normal, of course, but it opens. And then the throttle grip just rotates back and forth freely, because the spring on the throttle pulley is unable to restore it back to the closed position. When this happened the first time, I had to close the throttle by sticking my finger into the opening under the frame on the left side, and physically pushing on the pulley. When it's not so cold, everything works normally. And this happened even after I lubed the cable recently.

So I'm pretty sure it's not the grip itself that's getting caught. The sensation (when trying to forcibly open the throttle when it's stuck) feels like pulling the piston out of a syringe, like pulling something through a resistive housing. And since it goes away after I have the bike running for a few mins, I wondered if it's the sheath itself. Did you ever experience anything similar?
 

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Discussion Starter · #5 ·
Yeah, that's the only explanation I could think of as well. I thought the lube would've taken care of that, but I suppose a little bit of moisture can easily get there in these continuous cold conditions.
 

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(F800GT 2014)
This happened to me today, exactly how @lateral_G described it!
It was -5C° this morning and my bike was parked outside. Brought it inside for half an hour and the problem went away. However, after 10 min driving it got stuck again! Pulled over, turned off, and opened the throttle fully a few times and it was working again. After that driving on the highway for haf an hour, with temperatures going below -8C° at some places, no problem. (but I was paranoid so I would oaccasionally pull the trothle fullly back and forth, just in case).
This is the first time this happens to me, but this was also the first time the bike was parked outside overnight in such cold. I have ridden in freezing temperatures many times before (half an hour commute) but the bike was always in the garage.
The idea of ice building inside the throttle cable housing makes sense. When I pulled the throttle initially, it felt hard, as if some sand was stuck in the cable housing (and then the throttle was just loose, no resistance). It's possible some water is able penetrate the cable housing (it was raining the last time I rode before this incident), especially in an old cable. And the fact that it got stuck again after 10 min of driving (probably it did not unfreeze totally in the first place) indicates that the problem might be somewhere in front, not towards the engine where it's warm. I wonder if cleaning the housing and filling it with grease would solve the problem. I would also like to know where exactly the cable gets stuck, but I cannot think of a way to find this out.
 

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I think Maki and others are probably right about it being moisture in the cable housing. I wouldn't lubricate the cable. The outer cable sheath is teflon lined (to reduce friction). Lubricating is makes more sticky, and the lubricant itself will become thicker and gluggy. Don't know of any easy remedy. If riding regularly in sub-zero temps (when this is going to occur) perhaps a custom made throttle cable with a larger diameter outer casing (to give more clearance for the inner cable) may be the answer.
 

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I think I'd order and fit a replacement cable. If that fixes it you can investigate the old cable and dry it out and re-lube as a spare. A sticking throttle cable is dangerous its not worth taking the risk.
 
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