weird intermittent hesitation on the TT250

[letsride]

Is your clutch lever adjusted properly? Are you using a wet clutch compatible oil? And is yer hoof riding on that shift lever? I'm just thinking out loud.

[Thumper]

I understand the presumption that the clutch is involved since it is like the clutch is slipping transiently. But I wonder if the guide yoke(s) on 5th gear(s) is not fully engaging the dogs.

Does shifting into 5th feel like a deliberate "full throw"? If the rotating shifter guide that positions the yokes is not completely in the fifth gear position, the dogs could be incompletely engaged.

I am calling those guide yolks because I don't know the proper name for them. They moved transversely on certain gears on the counter rotating shaft, and drive shaft when you select a gear. Maybe get the rear wheel off the ground and manually go through the gears (shift with left hand while rocking the rear wheel back and forth with right hand so the dogs can align). See if it feels like a solid and complete chunk when it gets to each gear position, particularly between 4th and 5th. Do this with engine not running, of course.

[flopsweat]

Originally Posted by Thumper

I understand the presumption that the clutch is involved since it is like the clutch is slipping transiently. But I wonder if the guide yoke(s) on 5th gear(s) is not fully engaging the dogs.

Does shifting into 5th feel like a deliberate "full throw"? If the rotating shifter guide that positions the yokes is not completely in the fifth gear position, the dogs could be incompletely engaged.

I am calling those guide yolks because I don't know the proper name for them. They moved transversely on certain gears on the counter rotating shaft, and drive shaft when you select a gear. Maybe get the rear wheel off the ground and manually go through the gears (shift with left hand while rocking the rear wheel back and forth with right hand so the dogs can align). See if it feels like a solid and complete chunk when it gets to each gear position, particularly between 4th and 5th. Do this with engine not running, of course.

Interesting, I have no idea what any of that means . But I'll give it a try to see what happens. It does feel like the shift into 5th is a "full throw", just as solid as all the rest.



Like I said, this happens maybe one time, sometimes a second time a few seconds afterwards, and that's only about every few months of riding, and I ride a few times per week at the least. It's not a major pending concern at that rate, but I'm just trying to get a grasp on what might be happening in case it starts to get worse.

[Thumper]

Here's a good article on how it works (with correct termnology!)
https://www.uti.edu/blog/motorcycle/transmission

The things I called guide yokes are called shifting forks. This animation really nails it, and makes it easy to understand. The shift drum needs to get fully to the next position to get the gears lined up so the dogs are fully planted.

The video shows the detent with a sprung roller that holds the drum in position when in a gear.

They call the counter spinning axel the input shaft, and the drive shaft (with front sprocket) the output shaft.

[flopsweat]

Originally Posted by letsride

Is your clutch lever adjusted properly? Are you using a wet clutch compatible oil? And is yer hoof riding on that shift lever? I'm just thinking out loud.

I think so, but it did happen awhile ago and I have since adjusted the clutch, and it's happened since. Maybe I'll recheck that again just to be sure.
The ol' hoof isn't riding on the lever, I'm pretty good about getting right back to ball-of-toe being back on the foot peg immediately after a shift.