Honda CBR 1000RR Forums banner

Pirelli SC2 tearing

4K views 16 replies 10 participants last post by  lowrpm 
#1 ·
This is my nearly new SC2 after a day at Phillip Island. The RHS is perfect, but the left shows tearing for about 1/2 the circumference. Any experts out there with an opinion? Is this a tyre pressure issue (cold or hot tear), or am I just getting on the gas late? I do have an issue with harsh throttle response at the moment coming off closed throttle, so I know I am opening up later than I should.

Thoughts, anyone . . . .
 

Attachments

See less See more
1
#2 ·
looks like a cold tear to me. Pirelli's are awesome tires but they are super sensitive. PSI has to be correct as well as suspension set-up...even then, they can tear just from throttle abuse. Did you check your hot psi? (really need to stay on top of that with the Pirelli's, I usually have to adjust mine a couple times during the day to prevent tearing issues)



.
 
#3 ·
Yeah, it does look like a cold tear, but I just ain't sure. The truth is I spent all day in and out doing suspension setup, so I didn't pay too much attention to the hot tyre pressures. Off the warmers I had it right on the button (25psi), and because the day was quite mild (about 20 C), I just assumed the tyre was going to perform as expected and as it had in the past. It was only at the end of the day I noticed the tearing, and when I checked pressures again the rear was down at 24psi on the warmers, so I added 1psi. It got worse, which is a fair indication of cold tear I guess. . .

This is only my second set of SCs, so I don't know a lot about them yet (except they stick like shit to a blanket! :th_SmlyROFL:). I hadn't heard they were that sensitive - in fact the Pirelli guy initially told me not to stress too much about the pressures!!

What advice would you give if you're familiar with the SCs?
 
#4 ·
24 cold 28 hot is what what I shoot for. I typically have tearing issues later in the day when I'm really going for it and the ambient temps have risen... that's when you really have to track the hot psi and adjust accordingly...it's kind of a hassle but worth it. I've seen brand new sc's destroyed in 3 sessions from incorrect psi...they tear really easy. Also sometimes the tire compound can be an issue (in some situations an sc1 will work better than an sc2 and not tear as easy) your local Pirelli guy can advise you on what compounds work at your tracks. The Pirelli's can be tricky to figure out but it's really worth it...I love the grip and feel of them.:cool:
 
#5 ·
Interesting. When I got my first set I was given a target of 24 off the warmers and just 26 hot for an SC2 rear. I watched the pressures religiously and never had an issue with the rubber. Pirelli's website says target 26 - 29psi. I have picked up around 3 seconds a lap now I'm getting used to the tyres (1.44 at PI) so maybe when I was slow the lower pressure was ok but now it needs more. I feel stupid for not watching the pressures this time, because now I'm just guessing. Wish it was possible to send a pic to Pirelli and get some feedback. . .
 
#6 ·
This may be a result of running a rear spring that is too soft, the valving in your shock could be off, or it could be a rider issue. It is so hard to diagnose with just a photo as there are so many variables...
 
#7 ·
Absolutely agree. However, I have just had the suspension rebuilt for me and spent the day with a local suspension guru having it dialled it, so I am confident it's not spring/valving or settings. That leaves pressures and my riding. I admitted earlier my riding is not as it should be because I am getting a jolt when going from closed to partial throttle mid-turn because my fuelling is out. That means I wasn't rolling on the gas as early as I otherwise would, so acceleration is at max only when i've started to stand the bike up a bit.

That explains the heavier wear an inch in from the edge, but I don't think it explains the tearing by itself do you?
 
#8 ·
Going on the throttle too early out of tight corners can chew your tire like that.

I've ridden my Dunlops to that degree on a certain track last season. Could be you should try to use a higher gear if possible to reduce torque a little or just a tad higher pressure.
 
#9 ·
I have found Pirelli's to have a very limited pressure range - yet the only tool to manage tire pressure - the air gauge, is also often inaccurate...

I get my gauges calibrated every winter so I know I'm starting the season off with a consistent and accurate foundation. Otherwise, it's hit or miss when using the tire pressures recommended by the track side vendor or manufacturer...

YMMV
 
#10 ·
Too hard on the gas coming out of turns usually happens because you're too slow in the turn and not winding on power progressively as you come out to match available traction. I know for a fact that's what I'm doing to an extent because of the throttle issue, so it is a prime suspect.

I hadn't considered the possibility that my pressure guage has copped a knock since last used, but that is something I will check too.

Really appreciate the feedback all you guys are giving btw. It's really nice to have a group of people with some experience put their 2c in on this. :th_salute:
 
#12 ·
Sorry for the off topic comment...but damn your chains freaking clean LOL kudos brother:th_salute:
 
#15 ·
just go 1-2 psi up...
i run mine (Sc1fornt Sc2rear) at (cold) 28-28 and sometimes even 30-30 even on the road and i have no problems...
(problem is roads here are sticky as butter with 10w oil all over it...lol)
If you are not running at SBK levels of laps, going up on psi doesnt do harm...down on psi...well...check your tire...
 
#17 ·
The tyre pressure idea has some merit. The Island is hard on the left of any tyre cause you're leaned left for a long time at high speed. But I also agree the suspension could be involved. The reason I don't automatically assume its the shock is that it happened in the last session, just after I spent the first 5 sessions working on the settings with my suspension guy! But when I sent him a pic later and asked what he thought, he said maybe we need to do more work. So who knows? Guess I'll pay him some more and see what happens.


Sent from my iPhone using Motorcycle.com Free App
 
This is an older thread, you may not receive a response, and could be reviving an old thread. Please consider creating a new thread.
Top