Tires Slipping

[hoaxci5]

I just did a trackday at Willow Springs and for the first time ever I felt my front tire slide on me. I'm currently running Sportec M3's front and rear were put on at the same time.

I had a trackday at Barber and then a Deals Gap trip and some other random around town riding.. I would say no more than 1500 miles total on the tires.

So my question, are the tires toast?
Was I just asking too much of them on that turn?
(turn 4 left handed on the fast track at Willow)
As I had scraped the peg a few times so I was hanging off a ton to keep that from happening and running the turn pretty quick.
Is it because my front suspension is weak? (Stock internals with 15wt oil on a 01 SVS)

As far as my pace I would say I'm a fast beginner/slow intermedate.

Any input?

[GSXR RACER MIKE]

Your front end push could be from a number of things: Tires, weak springs, track surface (or debris on it like fluid, dirt, or sand), bad body position, improper bike set-up, taking a bad line and putting too much load into the front, or most likely a combination of some of these things and/or possibly others.

Proper springs are very important to allow the bike to have a cushion between the weight of the bike and the tires gripping the road. If your suspension bottoms out you no longer have that cushion and any imperfections in the road or inputs by you or the bike can easily cause a change in traction. An easy way to see if your forks are bottoming out is to put a zip-tie tightly around the stationary fork tube so the tube that slides will push the zip tie as it moves, this will show you the maximum travel the suspension encountered. When your springs are close to what's correct for your weight and ability you should be using apx the center 1/3rd of the suspensions travel, if your compressing the suspension all the way (or close) it's defenitely time to get the correct springs for your weight.

A common problem with alot of riders is not being smooth in their transition from braking to turning and end up getting somewhat of a pogo-stick action due to it. Not being smooth can cause variations in your traction as your suspension pogo's back and forth and tries to find it's equalization point. When done correctly the suspension would compress during braking and stay compressed as you turn the bike, no pogo action, just one continuos action. Damping can come into play here as well, too much damping and the suspension can act similar to being bottomed out because it can't compress as fast as it needs to. Not enough damping and the suspension will most likely have an increased Pogo like action which is bad for traction.

Of course the tires could be a little used up, and many people out of lack of not being able to point out the actual problem would default to saying you should put fresh tires on the bike - which indeed would help the issue temporarily (acting as a Band-Aid to cover up the real problem(s) if there are others). Since I'm not familiar with anything other than Dunlop's I can't give you any advice on your specific tires, but there is also the possibility that your approaching the limits of traction for that model tire. I have a feeling this is NOT the case, but without being able to actually check out your bike it's tough to tell what of many potential things may be causing the problem for you.

[hoaxci5]

Thats all great info, thanks a lot.

Stock SV springs are .706 and racetech's site says I should be using .85 so that is more than likely part of it.

I'm sure I'm not as smooth as any of the faster guys, but I didn't feel like I was abrupt in my motions, but I guess without truely knowing what smooth is thats hard to say too.

I'd like to run another trackday on the tires, and from the sounds of it as long as I replace my springs (which I planned to do anyways) then I might/should be ok.

The trackday organizer was talking about their school bikes doing 7ish days on a set of Pilot Sports, so I would think the M3's should be similar.

[GSXR RACER MIKE]

Originally Posted by hoaxci5

Stock SV springs are .706 and racetech's site says I should be using .85 so that is more than likely part of it.

I'm sure I'm not as smooth as any of the faster guys, but I didn't feel like I was abrupt in my motions, but I guess without truely knowing what smooth is thats hard to say too.

I took a 3-day long suspension seminar put on by Paul Thede (owner and originator of Race Tech) back in '98, that was a tremendous eye opening experience for me. One of the things he liked to say was "The best you've ridden, is the best you know". Now if you really put some thought into what he's saying there you'll realize that it means the best set-up you've ridden is the extent of your actual experience/knowledge as to what good really is. He also said that well set-up suspension will most of the time go un-noticed by the rider because it's doing what it should be and allowing you to do what you want the bike to do. I remember when I upgraded my suspension (damping and springs) on my 1st race bike, I was thinking "why in the Hell did I wait so long to do this?!" The bike became so smooth after that, it handled like I thought a bike should handle. After that upgrade I was instantly faster, smoother, and more confident while racing.

The difference in spring weights you posted above are fairly substantial, I think that's a major factor in your problem, definitely the 1st thing I would change (since unlike tires it's a long lasting change that really needs to be done in your case - and for apx the same cost as a pair of tires).

[Woodyracing]

stock SV front end sucks, actually it really really sucks
if your going to be doing much track riding, look into doing the full cartridge emulator thing (a very good suspension guru is a must). I had to mess with my geometry a good bit to get my SV working like I wanted it to, might not be necessary but it does help

my real concern is that you live in CA but rode the bike at Barber, Deals Gap and now your back at Willow Springs?

lucky bastard lol

[hoaxci5]

Originally Posted by Woodyracing

stock SV front end sucks, actually it really really sucks
if your going to be doing much track riding, look into doing the full cartridge emulator thing (a very good suspension guru is a must). I had to mess with my geometry a good bit to get my SV working like I wanted it to, might not be necessary but it does help

my real concern is that you live in CA but rode the bike at Barber, Deals Gap and now your back at Willow Springs?

lucky bastard lol

I think I have to take it a step at a time, my wife foots the bill since I move around the country because of her (Navy Doctor) so I need permission for goodies

I have already upgraded the rear shock (zx6rr) and lowered the front forks in the tubes approx 5mm, both of which made a HUGE difference. I think I'm only getting to the point of needing/being able to use the goodies that I want to buy.

The only reason I've been able to ride tracks like Barber and VIR, and gotten to play at Deals Gap is we just moved to CA about a month ago.

Lucky for me my wife rides and understands the addiction and also is fairly understanding of needing to feed my track addiction on occacation.

I can't complain about my riding opportunities, just my own ability and the equipment