Saturday practice started out hectic as usual, unfortunately. Got to the track around 7:15am and had to do a little work on the bike, change tires and go through tech before my practice started. I was in practice group 5, so practice didn't begin until about 9:00 but time disappeared as usual. I brought my tires to Pirelli for a new rear and a "take-off" front that they were supposed to be saving me from an Attack Kawasaki test. Well, they couldn't find the front tire, so Pirelli had to track down another front for me and didn't get my tires back to me until 15minutes before the first session. I scrambled to get the tires back on and get through tech in time to make the session. I assumed (bad idea) that the pressures were set from Pirelli so I went out without checking my pressures. The first session was a total wash because I had 60psi in the rear! So, next session I went out with the correct pressure and had a better session, but I was still struggling to find traction in the rear. The bike was just sliding and not going anywhere... on a 600cc bike with a stock motor and exhaust this shouldn't happen. I brought the bike into Dave Moss to check my suspension, he made some changes and I went out for my 3rd session. Traction was slightly better in the 3rd session but still not there. At this point we had one more chance to get it right because there are only four practice sessions on Saturday. So, we had to look for another solution. I changed my geometry slightly by adjusting the rear ride height to alter the swingarm angle, again it was slightly better but it was still really bad. Other 600's were driving away from me out of the corners and not sliding an inch, while I was just spinning myself silly trying to keep up. Best lap of the day- 1:47.8 in the last session.
Sunday morning practice I worked with Dave in the hot pits to try to find rear grip. I came in every 2 laps and made changes to the shock, with the track being cooler there was more traction than the previous day but ultimately the changes we made were the wrong way, and I would pay for it in my first race. I put fresh tires on for the races so we'd know it wasn't the tires.
Race 1 - 600 Superbike
I pulled the bike off the tire warmers with the pressures set and went out for the warm up lap. This was the first race of the day and I was starting 21st of 60something. I got a bad start and lost a couple of positions in the first couple corners. Fought back during the 1st lap and got the spots back. By the end of the 1st lap I was back to where I started. With a brand new tire I was spinning worse than the morning session, and what was worse was that it was taking all of my attention away, I was only focusing on keeping the back end of the bike underneath me. As the race went on traction got progressively worse and I started losing positions. Around lap 6 of 8 I had a near highside. While driving out of T7 the rear end stepped out suddenly, I paused on the gas and the rear end tried to highside me instead of coming back in line with the front. As I got kicked out of the seat I got back into the gas and the bike convulsed violently underneath me, almost running me off track. I got the bike stabilized and knew at this point I would have to do damage control the rest of the race and just bring the bike back in one piece. I finished 26th with a best lap of 1:48.7.
I found out after the race that the tire pressure gauge I was using was wrong. Causing the pressures to be set too low and overheat the tire as a result. This is why traction got progressively worse but not the reason that it was bad in the first place. With the help of Jim Williams, the Catalyst Reaction Suspension Tuning shop tech, we made some massive changes to the shock for the next race. Again I'd go out on a totally different set up I hadn't ridden before.
Race 2 - 600 Production
Got the bike off the warmers with the correct pressure this time, and headed out. I was starting 12th of 60something. I got a much better start this race and maintained my position of 12th. Traction was better but again not what it should be. At least the pressures were set properly in this race and traction was predictable all race. I was able to get into a rhythm and maintain a decent pace but still had a lot of attention on traction. I lost a couple spots during the race and finished 16th. Overall a much better race than race 1. Best lap of 1:47.3
The weekend proved to be a very frustrating one, but I learned some good things about the bike. Ultimately I've concluded that the traction issues were related to geometry, the swing arm angle was too steep causing the rear end to extend and top out the shock while on the throttle instead of squat and load the tire. The next race weekend should be much better, and hopefully I'll have some new parts in the form of a steering damper and quickshifter. Can't wait til' May!
-Michael Pesicka
AFM # 417
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