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Discussion Starter · #1 ·
Hello Wondering if anyone has any input on this tire wear It’s an s22 with about 1700 miles on it The leading edge on the sides sticks up higher than the trailing edge. I run the rear at 37psi. I’ve seen wear like this before when tire pressure is too low on other bikes, but running recommend psi usually makes the tires wear more evenly.
It’s kinda hard to see in the pics, but one side of the tread on the leading edgeis about 2mm higher than the trailing side.
I’ve heard not enough rebound damping can cause this, but nothing I can do about that.
Has anyone noticed this on their bike? Or is it normal and I and I shouldnot even think about it?
Thanks.
 

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I think it is due to a poor rear preload setting. What's your weight and in what position it's configured the shock?
 

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Discussion Starter · #3 ·
Hmm.
I’m 200-205 with my riding gear on.
When I bought the bike I immediately set the preload to the 2nd from stiffest position. It seemed really harsh over bumps. So I set it to one click harder than stock and and it’s been there since.
I measured sag with the shock in its current position. Forgot the exact number, but it was “in range”. I wanna say maybe 45mm?
 

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Looks like normal wear to me. You’re down to the wear bars, and it’s ready for retirement. (See what I did there?)

My S22 rear has a little feathering after almost half that distance and a track day. So, I wouldn’t worry.
 

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The sandy beach pattern looks great too - after watching one of Dave Moss's tuning videos I "know" this.
 

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Discussion Starter · #7 ·
Thanks for the input everyone. The feathering wasn’t too bad, just a little more than I’m used to seeing after playing with tire pressures.
I put a set of ContiSport Attack 4 tires on last night and went for a quick ride this morning. They seem to be a more round profile than the s22. Turn in seems less aggressive. Could be all in my head though.
I didn’t go with the s22 again because the center had over half the tread left, while the sides were down to the wear bars. Figure I might as well get a single-compound tire with a softer center 🤷‍♂️ No complaints about the s22 otherwise.
That said, the wear I’m seeing after a slowish 50 canyon ride is different from what I’m used to seeing. Almost like it’s it’s cold tearing maybe? I’m not used to seeing balled up little pieces on the tire after a canyon cruise.
Is this normal too?
4872
 

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@Ryan Mckay - I also installed S22's recently on my 890R, then went for a 5 day road trip on them - mixed bag of highway droning, fast sweepers, and some awesome tight technical roads. Pressures were set and monitored daily cold at 32.5-33 Front and 34.5-35 Rear. Ambient temps for the trip were usually 25 Celcius so mid-70's F and the ride pace was what I'd consider spirited but not approaching track levels of tire stresses by any means.

1900 miles on my tires now after returning home, this is a close up of the rear. I see a small amount of the same trailing edge raised lip as you mention but not as severe. Overall I'm happy with them and would expect to see a life expectancy of about double what I have now so maybe 4000 miles if I treat them right and don't do any track days.

Only thing I noticed swapping from the OEM Power Cup 2's was the increase in tire movement due to the huge increase in siping (tread) - under trail braking I could feel the front "wander" and squish way more than I would with the stock tires that are essentially slicks on the edges. The S22's gripped well though and overall seem like they do exactly as they are intended to do - be a mid-level street tire that can be ridden wet or dry, aggressively or sedate and offer a decent service life. Nothing special but for the price, I'm a fan.

BTW one last thing - just a question - have you had your tire gauge calibrated? I did years ago while racing by the Pirelli Tire Rep and mine was almost 2 psi under so he calibrated it for me and a couple weeks ago my friend ordered a new high end Motion Pro gauge and found his previous one was reading almost 6 pounds off - quite messed up! Maybe bring it by a local shop to make sure the pressures you are running are indeed accurate and if you've already done that - clearly suspension set up is the other major factor to address.

Good luck with the Conti's!
 

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Thanks!

Quoted from that link:

Are the edges of the tread raised? – If you have a raised area on either the leading or back edge of the tread, this is a strong sign that rebound damping on the forks or shock is set either too fast or too slow. Usually if it’s on the leading edge rebound is too slow, and if it’s on the back edge it’s too fast.

I had my rebound setting on the shock set to Sport (12 clicks out) but switched it back to Standard (14 clicks out) to slow it down and I'll monitor the change in the rear raised lip.
 

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^^^ Spot on Young Lion, rebound dampening contributes hugely to the wear on the leading and trailing edge of the tread. unfortunately theres no adjustment on the stock suspension to remedy this.
 

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Thanks!

Quoted from that link:

Are the edges of the tread raised? – If you have a raised area on either the leading or back edge of the tread, this is a strong sign that rebound damping on the forks or shock is set either too fast or too slow. Usually if it’s on the leading edge rebound is too slow, and if it’s on the back edge it’s too fast.

I had my rebound setting on the shock set to Sport (12 clicks out) but switched it back to Standard (14 clicks out) to slow it down and I'll monitor the change in the rear raised lip.
Maybe a bit late to the party but going from 12 clicks out to 14 clicks out will only make it worse.
If rebound is to fast, you need more damping, not less.
The setting is measured from fully closed, so more clicks means less damping.
You want to go to 10 clicks from fully closed instead of 14.
 

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@Ryan Mckay - I also installed S22's recently on my 890R, then went for a 5 day road trip on them - mixed bag of highway droning, fast sweepers, and some awesome tight technical roads. Pressures were set and monitored daily cold at 32.5-33 Front and 34.5-35 Rear. Ambient temps for the trip were usually 25 Celcius so mid-70's F and the ride pace was what I'd consider spirited but not approaching track levels of tire stresses by any means.

1900 miles on my tires now after returning home, this is a close up of the rear. I see a small amount of the same trailing edge raised lip as you mention but not as severe. Overall I'm happy with them and would expect to see a life expectancy of about double what I have now so maybe 4000 miles if I treat them right and don't do any track days.

Only thing I noticed swapping from the OEM Power Cup 2's was the increase in tire movement due to the huge increase in siping (tread) - under trail braking I could feel the front "wander" and squish way more than I would with the stock tires that are essentially slicks on the edges. The S22's gripped well though and overall seem like they do exactly as they are intended to do - be a mid-level street tire that can be ridden wet or dry, aggressively or sedate and offer a decent service life. Nothing special but for the price, I'm a fan.

BTW one last thing - just a question - have you had your tire gauge calibrated? I did years ago while racing by the Pirelli Tire Rep and mine was almost 2 psi under so he calibrated it for me and a couple weeks ago my friend ordered a new high end Motion Pro gauge and found his previous one was reading almost 6 pounds off - quite messed up! Maybe bring it by a local shop to make sure the pressures you are running are indeed accurate and if you've already done that - clearly suspension set up is the other major factor to address.

Good luck with the Conti's!
I am aware that this is an old post, but this is relevant still. My Duke 790 S22 tires show very similar wear. I used to see a very similar wear pattern on my CBR1000RR wearing Dunlop Q/Q2 and on a ZX6R wearing Q3. Talking about road use (not track).
 

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S22s did the same on my SV, and they do it on a friend's 800 BMW.
As the fampus philosopher said: they all do that.
 
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