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wwalkersd 09-03-2003 07:27 AM

Re: Trackday help
Did the other two go down at the same turn you did? Perhaps there was something slippery on the track that the crew missed. Sand, oil, water, etc.

If that's not it, I'd have to attribute it to pushing too hard too early in your first session. Were you perhaps trying to catch up to another bike? The "red mist" has caused many a rider or driver to exceed their limits.

Lowrez 09-03-2003 07:40 AM

Re: Trackday help
I'm going to assume that the track was fully inspected both before and after your accident so that we can rule out debris or a faulty surface.

You locked the front tire so it was how fast you tried to stop given the track and tire conditions. Maybe the tires were still too cold, maybe the track was, it doesn't matter. Did you think you had plenty of time to brake for the corner or were you pushing it? If you thought you had plenty of time, then you just don't know how to read your tires and track condition. Simple track newbie error. If you were squeezing the brakes as hard as you could in order to make the turn, you probably let memories of speed from your last track day impact your judgement and ended up making a slightly different newbie mistake.

cornercarver 09-03-2003 08:16 AM

Re: Trackday help
Well, you have 10,000 kilometers on a front tire, which even if it was still showing lots of tread, had certainly seen plenty of heat cycling, including one other trackday, I assume. This would surely have reduced overall grip, but more importantly, the many heat cycles will have raised the temperature at which the tire would become fully effective, and 2.5 laps probably wasn't enough to get them to temperature.

In future, look at it this way... If a tire is fairly worn, is the $150 you will save by not replacing it worth the expense of replacing your plastics, handlebars, exhaust pipe, tibula, etc? While I will use a tire that has seen some street use at the track, I wouldn't consider it on anything that had seen more than 2000 miles, and I'd think long and hard before using one with that many miles on it. Tires are cheap compared to skin and bone. You can always pull it off for the track day, and then put it back on to wear it out, if your budget requires it. You'll pay a bit for removal and reinstall, but nothing like the cost of the tire itself, assuming you remove the wheels from the bike yourself. A $40 insurance policy. It is amazingly easy to sell used tires on Ebay, too, if you are so inclined. Just be honest about their condition. I"ve heard of used tires with nails in them being sold for more than $50.

In short, I'd blame your tires, especially if other folks didn't lowside in the same place, implying a traction issue in that turn. I suspect you've learned your lesson about old tires, so get back out there and enjoy yourself.

One last little piece of trackside hearsay I'll pass on. I have no idea how true it is, but someone here will probably confirm or deny... I was told that every time a tire is heated up to temp and then allowed to cool, the temperature at which it achieves full grip increases. This means that the more times you heat cycle a tire, the harder it is to get them to temperature until it eventually becomes impossible. I imagine that street compounds are designed so that the temp increase is smaller, allowing them decent life despite hundreds of heat cycles. It also provides a second good explanation for tire warmers. Not only do you have traction on the first lap, but 1 trackday results in a single heat cycle, rather than 6 or 7. I'd guess that 8 hours spent at temp is probably not much easier on the tires than 7 heat cycles, but perhaps it gives a bit of extended tire life. Personally, I've never used them and I still manage to get at least 4 track days out of a set of 208GPs, riding in the bottom half of the fastest group on an Aprilia Mille, 2 days if I also ride them on the street. I always get rid of my tires BEFORE I can feel a decrease in traction, preferring to lose a bit of cash preemptively over losing a lot of plastic.


Lowrez 09-03-2003 08:56 AM

Vulcanized Rubber
Heat cycles further vulcanize the rubber. This causes the rubber to become more resist to changing its elasticity due to temperature changes. That's fine under normal street use, but at the track we want the tires to become a bit of a sticky mess so we can get that extra 1% of friction.

Also, street tires hit their operating temperature at lower temps than race tires, but also start to shred at lower temps/less abuse. Personally, I'll stick with going slow. I've been to the track, but it wasn't enough fun to justify going back.

James_Brown 09-03-2003 10:06 AM

Re: Vulcanized Rubber
An eminently logical explanation...

SeanAlexander 09-03-2003 10:22 AM

Re: Trackday help

Not having witnessed your crash and with no further explination from you or other eye-witnesses, I'll say that the cause is almost inpossible to ascertain, but it is logical from your description to assume that it was probably 80% B and 20% A.

"Stupidity" isn't really the term I'd use. "Ignorance" is probably much closer to the mark.

6,400 miles on a BT 010 + 2 1/2 laps of moderate warm-up aren't really dangerous in and of themselves, though I'm sure that grip was significantly below the level of a fresh and hot BT 010.

When you couple a decent tire that is admittedly past its prime with a fairly new track rider on in his first session of the day and then you ADD something like a spot of sand/oil/water/KY Jelly/etc... you have everything required for a trail-braking tucked front. Most of the time you will get away with these little mishaps, this time it caught you out. It will happen again,but most likely you won't crash from it next time, because you'll be expecting it.

If you want to be better prepared for it in the future, spend a little time on a dirt bike.

Hope this helps,


v2-90 09-03-2003 11:07 AM

Re: Trackday help
Great post. I'd have to also say that the fact that he's analyzing what he did wrong is a good thing.

I totally agree with the "spend a little time on a dirt bike" advice. IMHO, learning how to ride in the dirt first, makes for a much better street rider. I don't ride much in the dirt in the summer, too damn hot. By the time I start riding in the dirt in the fall though, I always feel like my riding skills have already deteriorated. After just a few weekends of dirt-biking, I feel so much more confident on the street - much more prepared for the unexpected. I started in the dirt at age 7 and by the time I was able to get a license to ride on the street, I was probably as prepared as I could have been (still young and stupid, but good reflexes...).

I don't ride on the track, but I can definitely see how riding in the dirt can help to make you a better track rider. Plus, you can do all of those "fun" things like wheelies, jumps, power slides, etc., all without getting a citation!

(going on 30 years in the dirt...)


ewok1 09-03-2003 11:34 AM

Re: Trackday help
i am with the guys who think you are being a little too hard on yourself. of the things that could have happened, a low side is an excellent result. and you survived. another tire consideration is that the tires were cupped. perhaps someone already suggested this. i know tires get less sticky as they go through cycles, but i get at least 8 track days out of dot tires. i don't trail brake much at track days(it's a track day, not a race), so maybe that is the difference. i am sorry about your bike and your ribs. i would say something trite, like next time let go of that lever, but i know you were down before you realized you were sliding. now you have your first crash out of the way. i didn't notice if you said you had slifders, but get some. they work pretty well. get back out there and enjoy yourself. but it coulda been mars. none of my crashes have been my fault. i know that for sure:-) i just realized you said at the end of the straight. i had a run off once at the end of a long straightaway because i was so busy braking, down shifting and getting my emotions under control that i forgot to roll off the throttle. then when the bike lurched i was afraid to tip it in. chalk it up to you were going too fast and hit the brakes too hard and you crashed. also if nesba has a group by you, go with them. they have a really good system.

Hadji 09-03-2003 11:48 AM

Re: Trackday help
Hmmmm...Dirt bike. As in Supermotard? ;-)

Singles and Twins Forever!

jaypuck 09-03-2003 12:50 PM

Re: Vulcanized Rubber
the most subtle joke I've ever seen on here. very nice.

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