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Tire slip at high torque, no TC

mjfink420

Active member
Had a strange one coming home today, when I got hard on the throttle in 2nd gear, up toward the power (~9K RPMs) it would feel like the tire gave a little slip. TC light did not come on, and the bike felt stable, it was almost like the tire was slipping on the rim? I'm going to mark the tire/rim and see if that's what it is, but wanted to ask if there were any other ideas? Issue with the cush drive maybe? My chain was a little loose, so I adjusted it when I got home, but didn't have time to ride it again to see if that was what it is. Kind of a small list of stuff it could be if it's not causing TC to engage right? Figure any time the rear tire is spinning, from the bike's POV, faster than the front, that's what gets TC to light up?

Any ideas?
 
Tire slipping on rim would trigger traction control. As the rear ABS sensor would detect the wheel turning faster, even if tire is not slipping. I vote clutch slip.
 
Tire slipping on rim would trigger traction control. As the rear ABS sensor would detect the wheel turning faster, even if tire is not slipping. I vote clutch slip.

Darn it.. Yeah, thinking it through a little more, you're right, tire on the rim would trigger TC. There's nothing in the cush drive that can "slip" is there?

Could I really be through a clutch in 22K miles? The only thing that doesn't feel like a clutch to me, it's not smooth. My experience with a worn clutch, the revs just go up and the bike doesn't "go" as much as it should. Honestly, I can't tell if the bike it "going" full bore, but if not way off, it's punching hard, just a "feeling" while it's doing it. It feels like "teeth" though, it's like a high frequency judder. Hard to explain. That said, it could be the clutch giving a little slip and catching again (quickly, a few times a second). I've never had a clutch fail like that, but it's not a bad guess, in fact, I think it's probably the most likely guess.
 
Darn it.. Yeah, thinking it through a little more, you're right, tire on the rim would trigger TC. There's nothing in the cush drive that can "slip" is there?

Could I really be through a clutch in 22K miles? The only thing that doesn't feel like a clutch to me, it's not smooth. My experience with a worn clutch, the revs just go up and the bike doesn't "go" as much as it should. Honestly, I can't tell if the bike it "going" full bore, but if not way off, it's punching hard, just a "feeling" while it's doing it. It feels like "teeth" though, it's like a high frequency judder. Hard to explain. That said, it could be the clutch giving a little slip and catching again (quickly, a few times a second). I've never had a clutch fail like that, but it's not a bad guess, in fact, I think it's probably the most likely guess.
Usually clutch slip happens first in the higher gears. Clutch slip in second would be weird. Try riding at normal speed/rpm in 6th and then going full throttle. If clutch slip is an issue this should make it happen.
 
Here's an idea. Slow TF down on the street.

WFO in 2nd gear, enough to spin the tire on the rim? On the street?

Take it to the track, and you'll see what "fast" really is.

And, get off my lawn! :ROFLMAO:
 
Usually clutch slip happens first in the higher gears. Clutch slip in second would be weird. Try riding at normal speed/rpm in 6th and then going full throttle. If clutch slip is an issue this should make it happen.

I did try that a bit tonight when I was riding, I wasn't able to get it to do it in a higher gear. And I couldn't really feel it in 1st either, but the range where it was happening (8K+, my guess), in 1st gear, the bike won't be able to put the power down, it cuts throttle/TC or wheelies.

If it's clutch slip, it's only occurring when the engine is making a lot of horsepower. I can't get to that range of RPMs in the higher gears. Sadly, 2nd is where I spend a lot of time in my local area, so it was maybe more noticeable to me than it would be most people.
 
A new clutch pack is less than $35:


If it’s anything like UJM design it’s pretty easy to replace.

It looks easy, I watched a video and read through a snip from the shop manual. I'm just not sure it's my problem. I'm going to have to take it for a ride tomorrow and see if I can really narrow it down to the clutch.

Like I mentioned, I did adjust my chain (it was pretty loose) and my clutch cable (it might have been a tiny bit tight), so maybe time to cross my fingers! ;)

Thanks for the help though, if anyone else has any ideas, please keep them coming. I just got the bike out of service for the fuel tank issue, I'd rather not take it right back in!
 
A new clutch pack is less than $35:


If it’s anything like UJM design it’s pretty easy to replace.
What does UJM stand for?


The term "Universal Japanese Motorcycle", or UJM, was coined in the mid-1970s by Cycle Magazine to describe a proliferation of similar Japanese standard motorcycles that became commonplace following Honda's 1969 introduction of its successful CB750.

OM
 
What does UJM stand for?


The term "Universal Japanese Motorcycle", or UJM, was coined in the mid-1970s by Cycle Magazine to describe a proliferation of similar Japanese standard motorcycles that became commonplace following Honda's 1969 introduction of its successful CB750.

OM

Coined in the 70's, still more true than not today. Japan makes great bikes, but they are far more similar to one another than different!
 
Looks good to me. No hooking or sharpness. The teeth all look the same.
If you were thinking the slip you mentioned, I don’t think it is the chain. Chain slip is usually rather violent and causes a bucking sensation.
OM
 
Looks good to me. No hooking or sharpness. The teeth all look the same.
If you were thinking the slip you mentioned, I don’t think it is the chain. Chain slip is usually rather violent and causes a bucking sensation.
OM

For anyone curious, this bike is around 22K miles now; I'm pretty happy with that amount of wear, especially if others agree that it's not cooked yet!

This wasn't violent. When it happened the first time, I immediately tried to do it again, it wasn't a "holy crap" moment, more a "what was that". If I had to compare it to something, it's like when you hit a tiny patch of sand on the road when you're accelerating, not at all like the tire stepping out or something more dramatic.

I may do the chain as preventative maintenance, it doesn't look bad to me, but 22K out of a chain seems like a lot, no? Anyone happen to know stock front/rear sizes of the 2022 XR off the top of their head? I'm thinking it's 17/45? Any reason to go with a rubber dampener in the front sprocket (seems to be offered as one of the options on the kit linked below)?


Here's what I'm looking at:


1734269766871.png
 
That ought to do it. Seems like, if I remember correctly, over something like 70hp generally requires a rivet style master link. I can recommend doing a test run on doing a rivet style master link. I have never used the proper tool on that style ML but have peened the links closed.
O-Ring chain is a bit tricky to hold together when a clip style ML is used. It may require some of the chain specific tools to help you get it together. I think the ones I have are by Motion Pro.
OM
 
Some video of me fooling with the chain, love to get your comments/suggestions. I don't want to color opinions, curious what you/others think?

 
At 1:30 there appears to be 2 links with a slight kink??

If I put my hands on them I can flatten them back out (with just a bit of force). I think it may be because it was cold, I use a wax lube on the chain and when it's cold, stuff gets "sticky". That said, the entire chain looks a bit "kinky" to me when you look at it around 1:45 or so up at the top. I'm not sure if that's normal or not?
 
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Had a strange one coming home today, when I got hard on the throttle in 2nd gear, up toward the power (~9K RPMs) it would feel like the tire gave a little slip. TC light did not come on,
There were 2 times when I had a K1300S where I thought I felt a slight tire spin.
On time wide open in 2 gear I felt a slight squirm.
Another time I used too much throttle when it was raining and I crossed a wide tar snake.
I didn't see the traction light either time but was not looking at the dash.
 
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