tyre gurus....how did these do?

[MoranC1]

Just completed my first track day, small track, was quite warm in the 15-20degree region id say. Tyres are bridgestone S21 evo. no warmers. front 28psi rear 26psi cold as per brigestone website.

anyone help with the tyre wear, its seems pretty ok?, but the edges of the rear tyre had alot of balling and "melting"
and the grooves, the front edge, i.e engine side of rear wheel are lower than the rear edge.

running in slick, with dtc -4 and preload set as best as possible, but im a bit light for the front.
didnt spend any time doing suspension adjustments as i was having too much fun haha.

 

[soofsayer]

Did you ride it home?

 

[r25sti]

looks ok to me for your first go.

 

[bmwbadboy]

They are not okay, but I would ignore it as this was the first run.

The grooves are worn more on one side than the other other. Plus you can see the outer compound starting to tear.

 

[MoranC1]

Did you ride it home?

nope got loaded into a van.

anyone got any info or tips for reading tyre wear? tried youtubing a bit but kind of going around in circles.

oh and the track is clockwise, with only 2 left turns....1 about 100+ and 1 about 50mph

 

[bmwbadboy]

nope got loaded into a van.

anyone got any info or tips for reading tyre wear? tried youtubing a bit but kind of going around in circles.

oh and the track is clockwise, with only 2 left turns....1 about 100+ and 1 about 50mph

The best info is paid unfortunately

 

[bmwbadboy]

 

[alex]

https://lifeatlean.com/motorcycle-tyre-wear-guide/

"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."

Yours is leading edge high and trailing edge low. If the bike holds its line do nothing but if it doesn't then the low speed rebound is too slow. So remove a click of rebound.

- Alex

 

[Monners]

That wear is fine for those tyres. You might clean them up with a bit of rebound but I wouldn't expect much since they are not race tyres. The balls of rubber are just where its not getting thrown off because you are not going so hard on the tyre edge due to being new to track riding. If you were not already doing it I would highly recommend checking tyre pressure immediately after each section since these type of sport tyres are plenty good enough but can get too hot and go mushy.

 

[fast_ryan]

Tyre Wear

+1. Good advice.

 

[MoranC1]

@monners i do believe thats what was happening. As i did a hand check on the rear after a session and it was roasting. And it did feel as though it was 'squidgey' after about 5 laps....

Due to it being my first TD on the s1k(ive done 3 before on a cbr) i wasnt sure how the feel should be. Bridgestone didnt give a hot pressure just a cold, what PSI increase should you seen? Im guessing aroynd 4ish?

 

[alex]

Apologies I was very tired and shouldn't have posted as I was backwards in my previous post.

I have now edited the post and it is now correct.

Changed from add rebound to remove it.
But its pretty good so its all marginal.

- Alex

 

[Monners]

Personally I would try running hot 34 front 26-28 rear. Starting at 26psi you'll likely shoot up to 30-32 or maybe even more since we have quite cool mornings. I dont know why they give cold pressures as they are verging on useless for anything but slow road riding. The way to work out if its correct is to measure after every session to check for change. If it's jumping up high then let a bit of pressure out. When using warmers you sometimes find it drops in which case add some air.

 

[MoranC1]

Apologies I was very tired and shouldn't have posted as I was backwards in my previous post.

I have now edited the post and it is now correct.

Changed from add rebound to remove it.
But its pretty good so its all marginal.

- Alex

i thought my wear would be the other way around, the leading (i assume the edge closest to engine) is the lower edge with the back of it being raised.

and would i be right in saying, going +2 on rebound, makes it return faster? or is it reversed i.e +2 makes the rebound return rate slower?

 

[r25sti]

That wear is fine for those tyres. You might clean them up with a bit of rebound but I wouldn't expect much since they are not race tyres. The balls of rubber are just where its not getting thrown off because you are not going so hard on the tyre edge due to being new to track riding. If you were not already doing it I would highly recommend checking tyre pressure immediately after each section since these type of sport tyres are plenty good enough but can get too hot and go mushy.

when i said its fine, this is what i meant. theres nothing to really worry about at this stage. ask tyre supports advise on the day and enjoy it. dont get drawn into the "is it perfect ". if there tearing up then do something as it gets costly but i cannot see any tearing on these so for now get some more days booked and just enjoy it.

 

[MoranC1]

sadly there was no tyre/suspension support on the TD as it was a private day. not so much worried about perfecting it, but i dont get alot of track time a year so like to know where i can improve prior to riding my next day, so less time adjusting and more time riding haha.

 

[r25sti]

sadly there was no tyre/suspension support on the TD as it was a private day. not so much worried about perfecting it, but i dont get alot of track time a year so like to know where i can improve prior to riding my next day, so less time adjusting and more time riding haha.

like i said they look ok to me. looks like you could push quite a bit more before your notice any issues. if it wasnt sliding about, loosing the front or spinning up the back imo your good to go. the center third looks good and the outer thirds have rubber build up that once you start to learn the tracks will push out to the edges. you could book on a track day with a good suspension support, for example at donny today we had 100% suspension who charges ?60 for support all day.

 

[MoranC1]

yea it felt ok most of the day, but i did have two small moments, one the rear slid out slightly just under light throttle, and the front slid out once aswell. but i do think that may have been an issue with them being possibly too hot. but ill keep an eye on temps/pressure if these tyres make it to another TD.

 

[r25sti]

your find track temp is also quite important when your pushing harder. just a few degrees lower than youve been riding at can cause slides where you didnt have slides before.

 

[scooby]

when i said its fine, this is what i meant. theres nothing to really worry about at this stage. ask tyre supports advise on the day and enjoy it. dont get drawn into the "is it perfect ". if there tearing up then do something as it gets costly but i cannot see any tearing on these so for now get some more days booked and just enjoy it.

basically this,just go do another day,and if theres a suspension guy there,pay th ?50 to get it set up for you.
people do get hung up on the smallest (and usually insignificant) things.until your riding at the pace you usualy ride at,things will wear/look different anyway.
nothing really wrong with your tyre wear,as far as theres nothing major wrong