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Discussion Starter #1
My brand new 2020 RR is the first bike I’ve had with a lean angle sensor/display. I’m wondering about the relationship between the displayed (actual) max lean angle, rear chicken strips, and tire pressure. I’ve only had my bike just over a week and 400 miles, all on the street. I don’t even have my first service and rev unlock yet. But with everything new, I see about a half-inch rear chicken strip (I don’t take it near the limit on the street) and have a fairly symmetrical max lean angle of about 43-51 degrees most rides where I hit some good curves. Leans over 40 degrees also constitute a minuscule amount of my street riding time.

I’m running stock tire pressures (near 36/42 psi) on the street, though am tempted to lower them (especially the rear) fairly substantially so they are closer to what I would run on the track. Reducing tire pressure would expand the contact patch and help absorb bumps when leaned. I would think that at a given lean angle, a lower pressure would also eat into the chicken strip. I don’t care about chicken strips except as a metric to better understand tire dynamics. I also understand there are many other variables such as tire type and body size and position (good hang off reduces lean at a given lateral acceleration).

I’m hoping to get some knowledge from those far more experienced. What can you tell me about the dynamics, tradeoffs, and anything else important here? What pressures would you recommend for fairly typical sport street riding with the stock tires?
 

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On my Power RS tires I run 34F and 32Rear.

Lowering the pressures on the rear will make the tire squat more increasing the contact patch causing more grip. You'll need to crank those tires over past 55 degrees to totally nuke the chicken strips. I don't advise doing this on the road re: potholes, deer, etc etc
 

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My brand new 2020 RR is the first bike I’ve had with a lean angle sensor/display. I’m wondering about the relationship between the displayed (actual) max lean angle, rear chicken strips, and tire pressure. I’ve only had my bike just over a week and 400 miles, all on the street. I don’t even have my first service and rev unlock yet. But with everything new, I see about a half-inch rear chicken strip (I don’t take it near the limit on the street) and have a fairly symmetrical max lean angle of about 43-51 degrees most rides where I hit some good curves. Leans over 40 degrees also constitute a minuscule amount of my street riding time.

I’m running stock tire pressures (near 36/42 psi) on the street, though am tempted to lower them (especially the rear) fairly substantially so they are closer to what I would run on the track. Reducing tire pressure would expand the contact patch and help absorb bumps when leaned. I would think that at a given lean angle, a lower pressure would also eat into the chicken strip. I don’t care about chicken strips except as a metric to better understand tire dynamics. I also understand there are many other variables such as tire type and body size and position (good hang off reduces lean at a given lateral acceleration).

I’m hoping to get some knowledge from those far more experienced. What can you tell me about the dynamics, tradeoffs, and anything else important here? What pressures would you recommend for fairly typical sport street riding with the stock tires?
33F 33R is a good starting point
 

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Discussion Starter #4
On my Power RS tires I run 34F and 32Rear.

Lowering the pressures on the rear will make the tire squat more increasing the contact patch causing more grip. You'll need to crank those tires over past 55 degrees to totally nuke the chicken strips. I don't advise doing this on the road re: potholes, deer, etc etc
Thanks. I need a bit of chicken strip as evidence to my disbelieving family and friends that I have a bit of remaining sanity.

I will only hit 55 degrees if I really screw up and go into a corner too hot. I'm hoping not to see 90 degrees.

I'll start by going to 34/34 and see how it feels. Should there be a significant difference?
 

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PSIs depend on rider's weight, ambient temps and style of riding. And no one cares about chicken strips if riding on the street.

If you're over 200lbs with gear, running stock 42/36 is fine R/F. Can reduce it a bit if it's cold out.
I'm 180lbs with gear, run 37/33 most of the time on the street. Running track PSIs on street tires or on street is stupid and asking for trouble.

Tire profile makes a big difference on chicken strips. 180/60 VS 200/55 Vs 200/60. Focus on what keeps you safe and confident in the turns.
 

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Discussion Starter #9
PSIs depend on rider's weight, ambient temps and style of riding. And no one cares about chicken strips if riding on the street.
Totally agree. I was just using it as a metric, not a goal. I'm very happy having chicken strips. I focus on technique, position, lines, balance, rhythm, relaxation, etc. when on the street and generally keep it within 70%. There's way too much downside to being overly aggressive.

If you're over 200lbs with gear, running stock 42/36 is fine R/F. Can reduce it a bit if it's cold out.
I'm 180lbs with gear, run 37/33 most of the time on the street. Running track PSIs on street tires or on street is stupid and asking for trouble.
I'm 6'2" and 210 naked, so I'm at the upper end in size.

Tire profile makes a big difference on chicken strips. 180/60 VS 200/55 Vs 200/60. Focus on what keeps you safe and confident in the turns.
The profile makes a huge difference obviously. The front has a much larger strip due to its near straight-down section to the bead.
 

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I am running stock tire pressure on the Michelin, hit 61 degree lean angle and still have sizeable strips. Didn’t even touch those three lines that taunt us on those tires!

I then dropped rear from 42 to 38. Made it past the first line, but still 2 more to go.

Maybe it’s the profile of the Michelin? Never had issues killing the strips on my pirelli tires?


Sent from my iPhone using Tapatalk
 

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Not sure what the standard tyres for the M Sport are in the US. In Australia they are Michelin Power Cup Evo. Recommended PSI in the manual is 36F 42R. I'm 72 kg and 42R seems a bit high for the road. I've been running 40. Maybe I'll drop it down to 38.
 

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Discussion Starter #15
Not sure what the standard tyres for the M Sport are in the US. In Australia they are Michelin Power Cup Evo. Recommended PSI in the manual is 36F 42R. I'm 72 kg and 42R seems a bit high for the road. I've been running 40. Maybe I'll drop it down to 38.
I have the Metzeler K3 Racetecs
 

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I usually wear mine off fairly quickly.
I don’t use sport tires though and my bike doesn’t have a lean angle gauge (KTM Super Duke GT).
Currently just put a set of Pirelli Angel GT II’s on.
Did a 60 mile scrub in on Saturday and they were at 1/2 inch.
Group ride yesterday and they were gone.
I run at 34/37, manufacturer recommended is 36/42.
 

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Discussion Starter #17
Per suggestions, I put a hundred miles on at 35/35 from the stock recommendation of 36/42. I surprisingly only noticed a very slight difference. If I lowered them more, my guess is that it would introduce some vagueness feel instead of the current sharpness. Others can correct me if I'm wrong. I'll continue to experiment. Is another downside of lower pressure reduced tire lifespan?

I'm beach vacationing away from the bike right now, but go in for my first service when I return on Monday. Though removing the 9K rev limit won't have any material bearing on the tire pressure selection.
 

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Per suggestions, I put a hundred miles on at 35/35 from the stock recommendation of 36/42. I surprisingly only noticed a very slight difference. If I lowered them more, my guess is that it would introduce some vagueness feel instead of the current sharpness. Others can correct me if I'm wrong. I'll continue to experiment. Is another downside of lower pressure reduced tire lifespan?

I'm beach vacationing away from the bike right now, but go in for my first service when I return on Monday. Though removing the 9K rev limit won't have any material bearing on the tire pressure selection.
I believe lowering the tyre pressure will lead to higher tyre wear. Need to find the right balance between tyre grip and tyre wear.
 

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I did my first track day on the Metzler K3s last weekend. 36F-34R cold worked very well in temps ranging from 65F to 95F in the afternoon. I had no idea today's street tires had that much grip. :grin2: I've always used slicks previously but wanted to burn these up since they were included with the price of the bike. Gawd! I forgot what a luxury having the kickstand on the bike was. And not going through the whole tire warmer thing was great too. :smile2:
 

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Per suggestions, I put a hundred miles on at 35/35 from the stock recommendation of 36/42. I surprisingly only noticed a very slight difference. If I lowered them more, my guess is that it would introduce some vagueness feel instead of the current sharpness. Others can correct me if I'm wrong. I'll continue to experiment. Is another downside of lower pressure reduced tire lifespan?

I'm beach vacationing away from the bike right now, but go in for my first service when I return on Monday. Though removing the 9K rev limit won't have any material bearing on the tire pressure selection.
Note also that tyre pressure changes 0.1 bar per 10 C deg, 1.45 psi per 18 F.
So if you measure or adjust tyre pressure on cold morning/ bike has been sitting in a cold garage, or hot day/ after you have been riding on the streets/ tyre is hot, it will make a difference.
 
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