Sears Point / AFM (04/22

Sears Point / AFM
04/22 - 04/23/00

Event Final Tech Info

Bob's 1999 Honda CBR600F4 (#0119)
Tires:	Front:	Dunlop 207GP	Pressure: 30psi
	Rear:	Dunlop 207GP	Pressure: 30psi
Gas:	Octane:	Chevron Supreme Pump
Suspension:	Front:	Fork tubes:	left: 31mm
			right: 31mm
		Sag:	26mm
		Preload:	1 lines showing, .95 spring
		Rebound:	1.0 turns from max
		Compression:	.75 turns from max
	Rear:	Ride height:	322mm bolt to bolt centers
		Sag:	24.5mm
		Preload:	27mm, 950 6" spring
		Rebound:	18 clicks from max
		Compression:	fast: 10 clicks from max
			slow: 4 clicks from max
	Damper:	Slow circuit:	3 clicks from max
		Fast circuit:	1.5 turns from max
		Sweep:	90 degrees / 6:00 position
Gearing:	Front:	15
	Rear:	45
	Ratio:	3.00
Jetting:	Main:	116 / 118	outside / inside
	Needle:	#2

Steve's 1999 Honda CBR600F4 (#0122)
Tires:	Front:	Dunlop 207GP	Pressure: 30psi
	Rear:	Dunlop 207GP	Pressure: 30psi
Gas:	Octane:	Chevron Supreme Pump
Suspension:	Front:	Fork tubes:	left: 36mm
			right: 36mm
		Sag:	26.5mm
		Preload:	1 lines showing, .95 spring
		Rebound:	1.25 turns from max
		Compression:	1.00 turns from max
	Rear:	Ride height:	316mm bolt to bolt centers
		Sag:	25.5mm
		Preload:	27mm, 950 6" spring
		Rebound:	18 clicks from max
		Compression:	fast: 10 clicks from max
			slow: 8 clicks from max
	Damper:	Slow circuit:	3 clicks from max
		Fast circuit:	1.5 turns from max
		Sweep:	90 degrees / 6:00 position
Gearing:	Front:	15
	Rear:	47
	Ratio:	3.13
Jetting:	Main:	116 / 118	outside / inside
	Needle:	#2

Race Times / Results:

	Bob	Steve	Bob	Steve
Races:	Formula I		600 Superbike
Time:	1:00p		2:40p
Temp:	74f		68f
Wind:	moderate		moderate
Air Density	91.5		92.5
Lap Times:	2.01.472	2.00.649	1.58.673	1.57.397
	2.00.198	1.58.875	1.56.869	1.57.393
	1.57.828	1.56.803	1.57.360	1.58.026
	1.57.184	1.57.917	1.56.953	1.56.500
	1.56.891	1.54.740	1.56.830	1.56.540
	1.55.020	1.54.933	1.58.615	1.56.991
	1.55.857	1.54.889	1.56.332	1.56.245
	1.56.515	1.54.678

Race Results:	25	20	30	27
Points:	14 (14)	19 (19)	9 (23)	12 (31)
Grid:	37	43	45	48
Total Starters:	58	58	59	59

Notes:

The race weekend at Sears Point with the AFM was our second 'warm up' session for the 2000 season. It had been almost one year since we'd been on the track, but except for some changes in T7 and T11, the layout was pretty much the same. T7 was widened in the middle, making it a double-apex corner, and T11 was shortened by about 50 feet to make room for an air bale barrier. I understand that the AMA configuration at Sears next month will draw T11 even closer to the front straight and is supposed to eliminate the chicane that the AFM uses to reduce speeds down the drag strip and into T1.

We had signed up for the dP Safety School session on Friday to get in a day's practice, but we were on the alternate's list and couldn't get on the track. We did a lot of catch-up work on the bikes and gear and waited for Saturday's AFM practice. It started raining as the first group went out on Saturday morning and the track was shut down until about 11:00. We finally got out on the track at about 12:00 and got in a grand total of eight laps. The AFM was running a new riders school, so there are no practice sessions for racers in the afternoon. We were able to get our bearings during those eight laps and check out the changes to the track.

I was still experiencing some severe headshake coming down the straights under full throttle. We double checked the steering head bearings (they were OK), and decided to raise the front of the bike by 5mm. We started the year at Willow running 10mm higher in the rear and 2mm lower in the front. Those changes probably decreased the rake on the front beyond the point of reasonable stability. Steve had a similar complaint. His front end was bouncing off the track on the small bumps. We backed off rebound and compression on his bike by .25 turns on the front, mounted new rubber for the races and waited for Sunday.

The changes to the bikes worked out very well come Sunday's eight lap practice session. We were probably fighting the same problem, just solving it in different ways. Steve had lowered the rear of his bike by 5mm at Willow last week, so his rake was already kicked out a little bit more than mine was. The races went really well, considering we started way back on the grid. 60+ bikes all heading into T1 can get real messy. We ran respectable times, even with all the traffic we had to work through, and Steve whipped my ass two-for-two races. I guess he was getting back at me for last week at Willow.

Next round, Formula USA / PACE at Willow Springs, 04/28 - 04/30/00.

Bob.