Cold Tires / Lean Angle --- Basic Question

[dmj120]

On the Twist2 dvd, in every riders' meeting, and at level 1 - it is said let your tires warm up; also keith say no quick-flick.

 

I understand how hard acceleration or filcking the bike too fast can cause you to have a bad day - but what about the lean angle? Having less than a dozen trackdays under my belt, it's obvious I'm not the fastest guy out there; and I always do at least 2 laps to warm the tires, I've felt the rear get a loose upon acceleration, which is kinda fun during these warm-up laps. But.... i never lean that far over - for fear of the washing out... my biggest fear is being one of the dumAzzes causing a red flag and taking other peeps' track time.

 

Can you lean all the way over (mind you, I don't drag a knee) before the tires are warm?

[faffi]

THat will depend on tyre model, tyre pressure, road surface temperature, asphalt texture and rider style - at least. Sport-touring road tyres will probably deliver full grip on a normal warm and sunny day after 300 yards but will "go off" after a couple of hard laps. Pure race tyres will not grip well until they are in their operating range, hence tyre warmers and vigorous riding needed for them. If you are a gentle rider, you would benefit from using tyres that work well over a wide range of temperatures, as in not race tyres. These will tolerate more load more quickly.

 

Don't know if this gave you any answers

[khp]

I'm not a mechanical engineer, and it's been many years since I had mechanics classes at Uni (ie: expect lots of hand-waving).

 

Cold tires will have less grip than warm (hot) tires.

Going through a turn with more lean angle requires more lateral grip than when using less lean angle (due to the centripetal forces).

As an example, using 45 degrees of lean will require up to 1 G of force, whereas 60 degrees of lean with require up to 2 G's of force.

 

In Norway, there is a special club for people going down on lap one: IFFR (Ikke Fuldført Første Runde). In English: Didn't Complete First Lap. Some people tend to renew their membership on a regular basis

Edited May 20, 2010 by khp

[Bullet]

Can you lean all the way over (mind you, I don't drag a knee) before the tires are warm?

 

No, not without warmers on tyres before, and even then, they're never quite the same operating temperature as really running. 2 laps is ok if your gradually build up your speed, but first corner max lean/cold tyres = crash typically.

 

Bullet

[dmj120]

Thanks!!!

 

That's it. I totally forgot about centripetal forces . Oh and in the US we have saying for people who go down in the first few laps --- another fck head tucked it... well maybe its only my saying

[dmj120]

No, not without warmers on tyres before, and even then, they're never quite the same operating temperature as really running. 2 laps is ok if your gradually build up your speed, but first corner max lean/cold tyres = crash typically.

 

Bullet

 

Thanks Bullet. That brings up another question.

 

Why the dual temp? Everyone I talked to says the single temp warmers are fine. Are there specific conditions that necessitate multiple temps? I'll probably get some warmers when I get to an upper "B" pace; so this is really just curiosity.

[Jaybird180]

Bullet,

 

What about simply using a street/ trackday tire? My understanding is that these are designed for quick warm-up. My PPs kinda let me know (the front does at least) that it's ready to begin turning things up; depending on the day, but I get feedback about 1/2 -3/4 way through the 1st lap. I still slowly turn up the juice.

 

I'm nowhere near the level where I need a dedicated track tire or much less warmers.

 

Just my $.02

[dmj120]

What about simply using a street/ trackday tire?

 

I'm nowhere near the level where I need a dedicated track tire or much less warmers.

 

 

I am on streets - bt016's. I feel pretty confident on these (I like the 'stones anyway), especially after Keith mentioned in the level 1 class "if you're not at racing speed, anything more is a waste." Something to that effect, anyway.

 

I'm not in need of warmers --- but dedicated track tires... if I could afford spare rims, I'd definitely have dedicated track tires (hell, i'd love a dedicated track bike). Commutting kills my tires and I always seem to need a new set to go to the track. But I knew wha'cha meant.

 

 

Don't know if this gave you any answers

Yes it did, thanks

[Kevin Kane]

Bullet,

 

What about simply using a street/ trackday tire? My understanding is that these are designed for quick warm-up.

JB;

I put a set of Dunlop Q's on my street bike and they made all the difference in the world from a confidence building perspective. I used to be much more tenative about steeper lean angles on the streets but the Q's are so much like a track tire from a grip and feedback perspective that I am planning on replacing them with Q2's soon.

 

Rainman

[Bullet]

All different types of tyres have different operating temperatures, i.e. where they're desinged to operate. Tyre warmers (certainly mid range and lower run at a pre-set temperature, and regulate this up and down a little, so they heat up and cool down a little. You'd need to check your tyre warmers to check what they operate at to be honest.

 

Do full on race tyres have full grip straight of warmers, (they kind you're likely to buy), no, but it still plentiful. If you then take this point onto road/track based tyres without warmers you've got to get them to their operating range and pressures, so you can expect that to take more than a couple of corners to get full grip. Different tyres warm at different rates basically, but it's a reasonable good rule of thumb to build up your speed over 2-3 laps, (more perhaps if the ambient is very low like it can be in the UK from time to time. )

 

Bullet

[acebobby]

more perhaps if the ambient is very low like it can be in the UK from time to time. + 1 on that Bullet

 

Here is something I have been thinking about for those that dont use warmers, warming tyres can sometimes be frustrating, especially when your getting passed by dudes that you know you are faster than but you need to rise above that!

The thing is if you look through your CSS books you have 15 drills to work on, can you remember what they all are? I'm not going to list them all here but as Keith said, not a good idea to quick turn on cold tyres, so were down to 14 drills! You see every time I go on track I pick a drill to concentrate on but I'm tweaking that plan a little so now I will concentrate on a drill that will work with cold tyres for the first 5 or 6 laps, going through my books, the majority of drills will work with cold tyres e.g. all the level 1 stuff except the quick turn, all the level 2 stuff, and pretty much all the level 3 stuff,

OK when I began writing this I thought I could eliminate more than 1 drill from the list, thats a testiment to how good the drills actually are so for me anyway my first 5 or 6 laps will be focused on throttle control rule #1 staying relaxed and all the visual drills!

 

Bobby

[khp]

more perhaps if the ambient is very low like it can be in the UK from time to time.

+ 1 on that Bullet

 

Here is something I have been thinking about for those that dont use warmers, warming tyres can sometimes be frustrating, especially when your getting passed by dudes that you know you are faster than but you need to rise above that!

The thing is if you look through your CSS books you have 15 drills to work on, can you remember what they all are? I'm not going to list them all here but as Keith said, not a good idea to quick turn on cold tyres, so were down to 14 drills! You see every time I go on track I pick a drill to concentrate on but I'm tweaking that plan a little so now I will concentrate on a drill that will work with cold tyres for the first 5 or 6 laps, going through my books, the majority of drills will work with cold tyres e.g. all the level 1 stuff except the quick turn, all the level 2 stuff, and pretty much all the level 3 stuff,

OK when I began writing this I thought I could eliminate more than 1 drill from the list, thats a testiment to how good the drills actually are so for me anyway my first 5 or 6 laps will be focused on throttle control rule #1 staying relaxed and all the visual drills!

 

Bobby, you're correct on your observations - but I still disagree on using tirewarmers.

 

My point of view is that a typical session 15-20minutes long, and with a laptime of 1-2minutes (depending on track & skill level), you usually don't get much more than 10 laps per session. So spending 5-6 laps to warm up the tires means that you're spending more than half your laps all day long, just to make sure your tires are warm. And that is a waste in my opinion.

Besides, big heat cycles tend to wear out tires quicker, than the tires staying warm all day.

 

Regards,

 

Kai

[Jaybird180]

So he probably only get about 8 laps per session

[Bullet]

Kai has an excellent reason on why to use tyre warmers really, and I agree with his point entirely. If you buy very sticky track tyres or you race, you really just don't want to warm them up and down (heat cycle them), as it is this heating up and cooling back down and not wear that ruins the tyres.

 

The other point on lost time per session is also relevant and if you work out the cost of those laps lets say for example 2 laps x 1:30 mins (per lap) = 3:00 mins per session. x 6 sessions = 18 minutes. Your total tracktime is 6 x 20 minutes = 120mins. so basically you're wasting almost an entire session of your day warming your tyres up. £150 pounds per trackday / 6 is the equivalent of 25 pounds. doesn't take many trackdays to warrant the cost of your tyre warmers does it..?

 

Bullet

[acebobby]

OK Kai and Bullet, I agree that I should probably be using tyre warmers and that they would benefit me with a bit extra track time but are there any negative's to using tyre warmers with road tyres?

Can road tyres be affected by heat cycling, I always aim to keep my tyres at a 5-7 psi increase from cold to hot so not to cook them!

 

Bobby

[faffi]

 

 

I am on streets - bt016's. I feel pretty confident on these (I like the 'stones anyway), especially after Keith mentioned in the level 1 class "if you're not at racing speed, anything more is a waste." Something to that effect, anyway.

 

 

These tyres are infamous for not giving any warning (for mere mortals, at least) before they let go - similar to the BT020 and BT021s. My brother had a rear 020 let go without warning at a track, highsiding him upwards enough to give him a full view of the track (a view he could have done without, according to himself ) and a 016 front letting go at relatively little lean at the road. He have this on video and you can see the bike just falling sideways and lots of scraping noises from metal hitting tarmac, then the tyre just gripped again a split second before he would have crashed, and he could continue on his way.

 

However, discussing tyres is about as useful as discussing what oil to use - different people will have various (strong) opinions. Some are also valid - different bikes and different styles stress tyres differently. Hence a tyre that suits you may not suit another - and the other way around.

 

Personally, I find the Pirelli Demon Stradas to be fantastic. They last noticeably longer than even the BT020 (not to mention the BT016) and are more compliant and have more grip than the 016s. I cannot say if they will slip predictably or not because I haven't managed to slide them since I only ride on the road and I'm not your fastest rider in the world. But I do lean enough that there isn't a hint of chicken strips and the tyres doesn't flinch when I accelerate at my semi-moderate levels of lean.

 

 

Metzeler ME-Z6 Roadtech is another tyre that apparently are very similar to the Pirellis as well as the new Pirelli Angel ST. Just if you ever feel like trying something else

[faffi]

Double post.

 

 

[khp]

OK Kai and Bullet, I agree that I should probably be using tyre warmers and that they would benefit me with a bit extra track time but are there any negative's to using tyre warmers with road tyres?

Can road tyres be affected by heat cycling, I always aim to keep my tyres at a 5-7 psi increase from cold to hot so not to cook them!

 

Negative impact on a street tyre from a tyre warmer? Honest, I don't know.

They are mostly done with the same technology, but with different rubber compounds obviously.

My gut feeling is that using tyre warmers probably wont damage a street tyre (very much). Probably not more than blitzing around the track will Of course, all tyres are affected by heat cycling - the question only remains "how much?".

 

Speaking of tyres being affected: water has a large impact, as it functions as a lubricant for the stones and tarmac you're riding on. That is supposedly why you will see larger tyre wear when riding in the wet, even when you're going slower (street or track).

 

Personally, I find the Pirelli Demon Stradas to be fantastic. They last noticeably longer than even the BT020 (not to mention the BT016) and are more compliant and have more grip than the 016s. I cannot say if they will slip predictably or not because I haven't managed to slide them since I only ride on the road and I'm not your fastest rider in the world. But I do lean enough that there isn't a hint of chicken strips and the tyres doesn't flinch when I accelerate at my semi-moderate levels of lean.

 

 

Metzeler ME-Z6 Roadtech is another tyre that apparently are very similar to the Pirellis as well as the new Pirelli Angel ST. Just if you ever feel like trying something else

 

I agree with Eirik on discussing tyres - it is very much a matter of 'taste', and a topic that can almost get you into a fist fight/take religious proportions.

 

Speaking of Metzeler vs Pirellis tyres: Pirelli owns the Metzeler brand. I keep forgetting the other 'pair' in motorcycle tyres, but I *think* it's Dunlop and Bridgestone.

 

Regards,

 

Kai

[Hotfoot]

I used warmers for the last two years, mainly because my riding buddies persuaded me that I was throwing away expensive track time warming up my tires, and also partly because I was running race tires and doing some racing and needed them for that. I was able to go a little faster on those stickier tires, but they wear out fast and they cost a LOT, and I HAD to use warmers. Without warmers, those tires (I was using Michelins) took longer to warm up and were really stiff when cold - pretty scary to ride on for the first few laps.

 

This year I got tired of buying really expensive tires every 3-4 track days and tired of fooling with warmers, so I put my kickstand back on, switched to Dunlop Q2s, and put the warmers and stands away for now.

 

The Q2s warm up REALLY fast, I can tell easily when they are warm, they have lots of grip, they cost MUCH less than what I was paying for the stickier tires, and they last a lot longer. So, although I lose a lap or so each session, when I compare the difference in cost for the TIRES, especially since they last a lot more days, I am much better off overall. And I LOVE not screwing around with the stands and warmers, and getting extension cords or a generator to my pit, etc. Could I run warmers with the Q2s? Probably, but they warm up so fast, why bother? Plus they are pretty easy to ride on cold - not like the race tires.

 

The only down side is that my buddies outrun me for the first lap, because they run warmers and go faster on the outlap. But I catch up.

[Kevin Kane]

The only down side is that my buddies outrun me for the first lap, because they run warmers and go faster on the outlap. But I catch up.

 

...and you didn't mention how many riders bin their bikes on their out lap; not an uncommon sight at Track Club events I've attended.

 

I am also a big fan, make it huge fan of the Q's for all the reasons you mentioned.

Rainamn