Tyres tyres tyres

kiwi60 · Post by **kiwi60** » Sat Jan 09, 2010 2:27 am

After I get the FZR dyno tuned later this month, I'll get the 17" wheel on the back and shout the bike a new set of tyres.

Unfortunatley the fact that I'm of scots decsent (and my bank balance won't allow for slicks with a life expectancy of 6 heating cycles), I've decided to stay with road based tyres.

I've been running a Pirelli Diablo Super Corsa Pro SC01 compound on the front, and I have to admit that it's a fabulous tyre - it warms up fast and hangs on like crazy, and I'm very tempted to stay with the mighty P brand, but there are so many new tryes coming through now I thought it would be worth while to see whose running what in a racing enviroment - and why.

So here you go - have your say

Mike_SS · Post by **Mike_SS** » Sat Jan 09, 2010 3:30 am

I run Dunlop GP Race slicks @ about $440 AUS per set. Not sure about the 6 heat cycle thing.

The last set I did 12 to 14 track day sessions, 4 x qualifying sessions , 2 x warm ups and 7 x races over two weekends and they made it through OK. (Did a P.B. in the last of the races

)

Hear what you are saying about the Pirellis though. I run them on my Ducati road bike... very nice..but not real cheap here.

spook · Post by **spook** » Sat Jan 09, 2010 5:46 am

Heat cycles? That's six or ten track or race sessions with warmers. they would be worn out by then anyway. Buy some warmers

JasonL · Post by **JasonL** » Sat Jan 09, 2010 6:13 am

Kiwi,

I'm direct Scottish, arrived in '81 and you'll love this - in 2008 I did the whole season on a secondhand Michelin rear that cost me $50, it's now on my FZR to do a track day on! Admittedly it was on a VFR which didn't exactly rip the pavement up and the FZR should finish it off, but you can get by cheaply tyrewise. Having said that, good rubber means so much, even just for confidence's sake. The truth is, I think modern tyres are so good that almost anything is going to be ok. Over the past couple of years I've run Dunlop, Michelin and various Bridgestones and found most of them to be excellent. Mind you, despite how popular Bridgestone's are, I heard they have not had any development put into them for a few years, so they are in effect an old tyre now - Dunlop and Pirelli are current. Michelin just seem impossible to get. It often comes down to profile, pressure and compound more than brand - what suits you and the bike best will often come down to a bit of experimenting. On a bigger bike running club races (ie: short heats) as a general rule of thumb I'd run a soft front and a medium rear. And one manufacturer's profile may not be quite the same as another, even if they are the same on the sidewall (you probably know all this so I'll go now!)

sickle44 · Post by **sickle44** » Sat Jan 09, 2010 5:51 pm

Hey Graham,

Personally myself, if you've got to use Road tires, I'd be sticking with Michelin or Bridgestones. MotoGP can't be wrong, although, yes I know they now longer use Michelin but.....

Michelin now has there custom tire choosing site which I understand is pretty good. I've been at the track with my Pilot Roads and they worked very well for that even, but I wasn't running really hard. If I were racing, I'd pony up for Michelins stickiest road tires.

Just my

spook · Post by **spook** » Sat Jan 09, 2010 8:22 pm

I just want to clarify what I meant. Put your warmers on in the morning do six sessions putting the warmers back on as soon as your back in, and at the end of your day you have 1 heat cycle. In my mind any way. A bit like heat cycles of a gas turbine engine. lol

I think Jason has it, though I will never buy second hand tires again. Last time I went over the bars it was on crusty old rubber. As a rider, i think i would be hard pressed to push any decent rubber to it's limit. If you do use second hand it pays to actually know it's history personally. i have had second hand super stock tyres that had only been used for a qualifying session and they were great.

JasonL · Post by **JasonL** » Sun Jan 10, 2010 5:49 pm

I should clarify too - when I say almost anything should be ok, I don't mean road touring tyres for example!! just that all true sports/race tyres are now so good that any of them will be more than adequate. The treaded versions such as Pilots etc offer something slicks may not, which is they potentially get a bit more heat into the tread more quickly, which can be handy in cold and / or short race conditions. I'm not sure about the heat cycling thing, but I do believe a lot of cheaper tyre warmers run too hot and quietly bake the rubber - this may be a bigger problem than actual heating up and cooling down. Whatever the state of your tyres, new, old, crusty, whatever the conditions, hot, wet, cold etc I always, always take it easy for the first few laps out until the tyres get some heat into them and you progressively get that fine top layer of old rubber off them. And obvious stuff but always check pressures before going out first up, plus at least one check through the day.

Mike_SS · Post by **Mike_SS** » Sun Jan 10, 2010 5:55 pm

I do believe a lot of cheaper tyre warmers run too hot and quietly bake the rubber

This is one of my questions. I have heard different opinions on what temp tyre warmers should run at. I have been running mine at 80 though if there is a bit of wind they struggle to hold that anyway,

kiwi60 · Post by **kiwi60** » Sun Jan 10, 2010 10:32 pm

This is all good - keep it coming

spook · Post by **spook** » Mon Jan 11, 2010 3:17 am

80 deg is fine. I have KLS carbon element warmers (no wires or hot spots) they heat evenly to the rim. I bought the cheaper (sport) version specifically because they only heat to 75 deg C, and avoid cooking the tyres.

A lot of the pro warmers are ajustable up to and over 85 degrees. These sorts temps I believe can harden the rubber, as can hot spots associated with the uneven heating of wire element type.

sbutler · Post by **sbutler** » Mon Jan 11, 2010 5:43 am

I have a couple sets of Pirelli Diablo Superbike slicks for sale.
Soft fronts SC1, Hard rears SC3.
One set is about half gone, still get a couple of track days from them. The other set has only test laps & are near new. just roaded. If you want them PM me. The two sets $400 +post around $50.

By the way Jason, you wont get more than two meetings out of tyres on the FZR

Oh & you are correct again Jay, tyre warmers shouldnt be set at anything above 75deg or roasting can take place. If the tyre has a blue shinny look, its overheating.

JasonL · Post by **JasonL** » Mon Jan 11, 2010 5:45 pm

Steve, quite right!!

Kiwi the other thing I have some trouble with is tyre pressures - more about how much "cold" pressures vary, for example if its 10 degrees then you are going to get a different reading than if its 30, naturally enough. So when manufacturers or bike shops or whoever talk about cold pressures, at what ambient temp exactly??? The difference can easily be 10% depending on the weather. I think a lot of people have a tendency to run pressures that are too high, I try to start on the low side and add a little bit if I think that's what it needs, but really its whatever works for you. As a general rule of thumb if its about 22 degrees I would run 28 front 29 back, that's just my baseline.

kiwi60 · Post by **kiwi60** » Mon Jan 11, 2010 6:16 pm

Kiwi the other thing I have some trouble with is tyre pressures - more about how much "cold" pressures vary, for example if its 10 degrees then you are going to get a different reading than if its 30, naturally enough. So when manufacturers or bike shops or whoever talk about cold pressures, at what ambient temp exactly??? The difference can easily be 10% depending on the weather. I think a lot of people have a tendency to run pressures that are too high, I try to start on the low side and add a little bit if I think that's what it needs, but really its whatever works for you. As a general rule of thumb if its about 22 degrees I would run 28 front 29 back, that's just my baseline.

When I started racing back in the 90's (on a '82 GPZ1100) I was given some good advice by one of NZ's top racers regarding setting tyre pressures, start a little below normal road pressures (I usually start about 30psi front and 32 rear on the race bike), and as soon as you get off the bike in the pits after practice, before you even take your helmet off, check the pressure again.
If the pressure is within 3psi of the orginal setting, your about right, if it's increased more than this - add a couple of more psi.
Too low a pressure will cause the tyre carcas to over-flex and heat the air up inside, too high a pressure and the tyre will start moving around too much when on the track (this is why you start at a lower pressure than normal).
As the day warms up, it pays to go through this proceedure after every race - it's simple, but it does work.

Wet weather racing definatly benefits from running a lower pressure, but as I tend to watch those races rather than participate, that's an area that doesn't worry me too much.

The flash guys use nitrogen instead of air, but I'm not one of them.

Mike_SS · Post by **Mike_SS** » Mon Jan 11, 2010 6:31 pm

Optimum tyre pressures are also dependent on tyre types and bike set up. I am by no means an expert and I am still learning by trial and error. With the Dunlops I run 27 rear and 32 front 'off the warmers' on a typical high 20s to low 30s degree Queensalnd day

I also check them as soon as I come in to see how much difference there is.

spook · Post by **spook** » Mon Jan 11, 2010 6:49 pm

Hmmm, Air is 78% nitrogen to start with. I looked into nitrogen, I went down to my gas supplier and queried him, he reckoned if you have a good water filter on your air pump outlet you would be doing enough, as moisture in the air can convert to steam. Nitrogen will still expand and contract... The guys with the bottles could probably find some tenths else where

I actually adjust my pressures once the warmers have been on for 30-40 min, and I run about 29-30 hot. But don't pay any attention to me though. My personal reckoning is that 75 degrees is a better base than ambient?

If it's cold, do you run lower pressures or higher? lol.

spook · Post by **spook** » Mon Jan 11, 2010 7:18 pm

Also, I know a few guys who have made up sort of power boards for their warmers, incorporating a light dimmer rheostat, so they can turn down their crap warmers to a temp that doesn't leave their tyres looking like a blue bottle wasp. It sometimes amazes me how much time folk waste working around crap equipment.

I reckon the biggest thing for your confidence has to be pre-heated tyres. You aren't left wondering am I up to temp yet? If you start a session with a question mark in your head, I reckon it remains there. If your racing, it is almost irresponsible to run without them, a tentative rider is a dangerous one. Just my 2 cents....

stan · Post by **stan** » Mon Jan 11, 2010 10:40 pm

how long have tyre warmers been commercially available, and how long have we been racing!!!

Sh1T, Bassett an i used the tyre rotation process in warming our tyres, you know, leave the bike in the sun between races and rotate the tyres to get some heat on them

Just get on a ride the thing already

stan

sbutler · Post by **sbutler** » Mon Jan 11, 2010 11:28 pm

Mike_SS wrote:Optimum tyre pressures are also dependent on tyre types and bike set up. I am by no means an expert and I am still learning by trial and error. With the Dunlops I run 27 rear and 32 front 'off the warmers' on a typical high 20s to low 30s degree Queensalnd day

I also check them as soon as I come in to see how much difference there is.

Remember Mike the FZR is rear heavy, so I use to run 30r 28f cold. [around a 28deg day]
The yzf is more a 50-50 bias so you would get away with your pressures.
I would warn against using them on the FZR..

spook · Post by **spook** » Mon Jan 11, 2010 11:34 pm

So you did feel that putting warmth into the tyres was important? You have to move with the times Stan.

Mike_SS · Post by **Mike_SS** » Tue Jan 12, 2010 3:09 am

Remember Mike the FZR is rear heavy, so I use to run 30r 28f cold. [around a 28deg day]
The yzf is more a 50-50 bias so you would get away with your pressures.

I guess it will be trial and error. I will be using a higher rear pressure than last year (even on the 750). I brought the front pressure up after some advice from one of the coaches last year and it seems pretty good.

I have read somewhere that Dunlop reccomend 32-33 off the warmers for 600s. Not sure what the difference should be for other bikes.

leave the bike in the sun between races

See this done a bit as well. Some warmth is better than none.