MOTORCYCLE · TRACKS & PERSONAL RECORDS

Ten circuits, one notebook.

Every track teaches something different. This is my personal record sheet: layout, length, best lap and speeds. Race and track-day laps are both included, so treat it as a diary rather than an official record book.

The Ridge, Shelton, Washington

A 2.47-mile, 16-turn circuit with real elevation change, and the track I have raced and trained at most recently. I have raced it without the chicane in WMRRA, and ridden track days on the chicane layout used for AMA/MotoAmerica. I keep both sets of laps.

Onboard camera frame at The Ridge on August 18, 2026 showing 25 mph, 152 bpm heart rate and 13 degrees of lean — Onboard frame from the Aug 18, 2026 track day: 25 mph through a slow corner, heart rate 152 bpm, lean angle +13°.

Best lap at The Ridge over the years without the chicane and with the AMA/MotoAmerica chicane — Best laps by year. Without the chicane: 1:49.40 (2018 race), 1:47.78 (2019 race), 1:47.50 (2022). With the chicane (AMA/MotoAmerica configuration): 1:56.56 (2021), 1:54.08 (2023), 1:53.70 (2026).

Why it keeps teaching me

Long fast sections reward patience on the throttle.
The downhill braking at Turn 7 is a place where the rear brake helps (see Riding craft).
The race lap record is about 1:44, roughly three and a half seconds quicker than my best.

Worth watching

External links open in a new tab.

Thunderhill Raceway Park, Willows, California

A 15-turn, 3.0-mile circuit in the Sacramento Valley that I first raced in 2005 and visited again on September 13, 2026. The map marks the on-camber, off-camber, uphill and downhill sections that make it so interesting to learn.

Map of Thunderhill Raceway Park with turns 1 to 15 — Track map by Race-Graphics.com, shared by AFM.

Onboard frame at Thunderhill on September 13, 2026 showing 160 mph and a heart rate of 159 bpm — Onboard frame, Sep 13, 2026: 160 mph, heart rate 159 bpm, +2.9 g.

Sherwick leaning the red and black Aprilia RSV4 Factory, number 689, over the curbing at Thunderhill

Sherwick leaning the Aprilia RSV4 Factory, number 689, through a corner at Thunderhill

Corner photos: Dito, GotBlueMilk.

My best Thunderhill East race lap is 1:57.382, from an AFM round on September 7, 2008. See it in the full table.

All tracks and personal bests

Type to filter by track, state or layout. Speeds are in mph (average and, where recorded, maximum).

18 of 18 layouts

Swipe the table sideways to see every column →

Track / layout	Where	Dir.	Turns	Miles	Best lap	Speed	Notes
The Ridge (no chicane)	Shelton, WA	CCW	16	2.47	1:47.504	82.7 avg · 169.3 max	Moto Vixens trackday, Sep 2, 2022. Race best 1:47.778 (82.5 / 171.5) at WMRRA Open Supersport, May 5, 2019.
The Ridge (chicane, AMA/MotoAmerica configuration)	Shelton, WA	CCW	16	2.47	1:53.7	79.2 avg · 147 max	Tracktime track day, Aug 18, 2026 (1:54.060 on my AiM logger).
Portland International Raceway (no chicane)	Portland, OR	CW	9	1.915	1:12.611	97.5 avg · 181.3 max	Slowest speed 38.6 mph.
Portland International Raceway (chicane)	Portland, OR	CW	12	1.967	1:22.775	85.4 avg · 171.2 max	Slowest speed 35.1 mph.
Utah Motorsports Campus: Full course	Tooele, UT	CCW	23	4.5	3:07.95	86.2 avg
Utah Motorsports Campus: Outer (perimeter)	Tooele, UT	CCW	15	3.05	1:58.686	92.5 avg · 171.9 max	2018 MotoAmerica Championship of Utah, 2016 Aprilia RSV4 RF. Official top speed 174.137 mph.
Utah Motorsports Campus: East	Tooele, UT	CCW	15	2.242	1:38.886	81.6 avg	On a 2015 Yamaha R1. On the 2016 Aprilia RSV4 RF: 1:39.054 (81.5 avg · 127.8 max).
Utah Motorsports Campus: West	Tooele, UT	CCW	10	2.183	1:35.794	82.0 avg · 138.3 max	Slowest speed 36.0 mph.
Las Vegas Motor Speedway: Classic	Las Vegas, NV		8	1.8	1:22.731	78.3 avg
Chuckwalla Valley Raceway	Desert Center, CA	CW	17	2.68	1:55.417	83.6 avg	Counter-clockwise: 1:55.490 (83.5 avg).
Reno Fernley: Course H	Fernley, NV	CCW	21	2.4	1:55.07	75.1 avg
Reno Fernley: Course C (perimeter)	Fernley, NV	CCW	30	3.2	2:41.413	71.4 avg
Willow Springs: Big Track	Rosamond, CA	CW	9	2.5	1:27.054	103.4 avg	Fastest average speed of any layout in my notes.
Willow Springs: Streets	Rosamond, CA	CW	16	1.8	1:23.77	77.4 avg
Buttonwillow (#13)	Buttonwillow, CA	CW	13	3.0	1:53.601	95.1 avg	Counter-clockwise #13: 1:58.680 (90.4 avg).
Buttonwillow (#15)	Buttonwillow, CA	CCW	12	3.1	2:00.81	92.4 avg
Sonoma Raceway (AMA layout)	Sonoma, CA	CW	11	2.22	1:44.210	80.1 avg	On a Ducati 1098R at an AFM championship round. 2019 MotoAmerica Sonoma on the 2016 Aprilia RSV4 RF: 1:46.710 (74.9 avg · 130.2 max).
Thunderhill Raceway: East	Willows, CA	CCW	15	3.0	1:57.382	92.0 avg	AFM race, September 7, 2008. Map and 2026 photos.

Laps come from my logger (AiM), official timing, or a stopwatch. Where my notes list two values for the same lap I show the official one.

Race laps by circuit and season

My fastest race lap each season at every circuit I raced from 2005 to 2019, plus my track-day laps on The Ridge chicane layout. Faster is up.

Sherwick fastest motorcycle lap by season and circuit, 2005 to 2026, including both layouts of The Ridge — Fastest race lap in any class, from my 2005–2019 race spreadsheets. Dashed lines mark seasons I skipped at that circuit. Open circles are track-day laps on The Ridge chicane (AMA/MotoAmerica configuration), which I have not raced.

The Ducati seasons (2005–2011) come from AFM result files that may contain mistakes, so a lap 3 or more seconds quicker than any other that season at that circuit is left out. The Aprilia seasons (2012–2019) were recorded on a datalogger and are all shown. No race lap times are recorded for Portland International Raceway. The table above also includes track days, logger and official timing, so some bests there differ from this chart.

Reading the table

Direction is the way the circuit is run: clockwise (CW) or counter-clockwise (CCW).
Layouts matter: Utah Motorsports Campus alone offers four, and the best lap on each is a different story.
Mixed sources: some laps are from races, some from track days. The gap between them is not a measure of fitness.