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AFM Race Report - Infineon Raceway (Sears Point)
- May 29-30, 2004

written June 3, 2004
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Infineon Turn 2
© 2004
It was bad enough the last race was rained out, but then we had to wait six weeks for out next race weekend. The benefit was having lots of time to tweak bikes, but after starting the season at Buttonwillow in March, waiting 9 weeks for the next race seemed like undue punishment for something we didn't deserve. Finally, the race weekend came, but all was still not well. Formula IV was canceled due to a delay at the end of the day. It was almost as bad of a let down as not racing in April.

All was not bad, though. The six weeks between events allowed me to work on a performance issue with the 450cc motor, and when racing finally did come, 450 Superbike was almost enough to make up for the missed races.


Motor Development

Ring Seal Issues

"The devil is in the details." Or so I've heard. Well, when it comes to engine development, this should be the builder's mantra.

The first G-Force VFR 450cc engine was running about this time last year. That engine peaked at 82 HP on pump gas, and made 84.5 HP on Nutec race fuel. But, that power was seen only the first weekend we ran it. Later dyno runs showed it just below 80 HP. In all runs, we saw a lot of flutter in the power at the top end (lots of peaks and valleys as opposed to a smooth curve), and later, we saw a consistent 2-3 HP drop off in power from about 12K RPM up. We looked at several possible causes, but never found a smoking gun.

Over the winter, a new engine was built based on an RVF400 motor instead of the VFR400 motor used last year, and using Carrillo steel rods instead of titanium. Dyno tests on the "B" motor, as we called it, showed the same fluctuation in power as before, including the 2-3 HP drop off, but this new motor never dynoed past 78 HP. We expected the RVF motor to do better than the VFR motor, but it was worse. This wasn't an apples to apples comparison, however. Titanium rods vs. steel rods, and the VFR vs. RVF differences could easily explain the discrepency. The key detail, though, was we still had the 2-3 HP drop off. A test finally verified the cause. We were having ring seal issues. The rings would lose their seal at higher RPM and higher heat, and the engine would lose power.

The likely cause? The rings were hitting each other at the ring gap due to heat expansion, causing them to buckle. So, we took the engine apart, and Mike Norman did a thorough inspection. Not only did we find the ring gap was too small, but also the cylinders were out of round more than originally measured. Apparently the cylinders warped a little under usage. When Mike originally received the cylinders, he measured them, and they were within tolerance. After running the engine, stresses in the metals worked against us, causing changes due to heat cycling, and now the cylinders were no longer within tolerances. It's a metallurgy thing. We had the original sleeves bored out and aluminum sleeves with a nikasil liner installed. It turns out, this may not work very well with a VFR/RVF engine due to how the cases are made in the first place. Of course, we did this originally because simply boring out the original iron sleeves isn't a very good option either. More investigation is needed on this.

We didn't have an immediate solution to the out of round cylinders, so the engine went back together. The out of roundness didn't pose a reliability issue, it just meant the ring seal wouldn't be perfect, and we wouldn't get maximum power. The rings were now properly gapped, and Mike did a modification to the pistons to help deal with the cylinder issue. Back on the dyno, and we still had the peaks and valleys, but the drop off was no longer present. The main issue was solved. The peaks and valleys didn't worry me much because the engine was still being broken in. The true test would come after a full race weekend, once the rings were totally broken in.

Following the Infineon race weekend, with the engine fully broken in, we tested it. Not only were there no signs of the 2-3 HP drop off, but the peaks and valleys were gone. This was the first time one of the 450 motors showed such smooth, consistent dyno curves. It still wasn't making 80+ HP, but it was solid and consistent just below 80HP. The 2-3 HP drop off and inconsistency of dyno runs was preventing us from trying other performance improvements because each dyno run was affected by heat and ring seal failure. Now, with consistent runs, we could start working to regain the 80+ HP.

Other Changes to the "B" Motor

We assembled the "B" motor with a few other changes from the first assembly. We put the VFR heads from the A motor on this time, but are still using the RVF cams and RVF ignition system. Also, Mike played with the cam timing and ignition timing, but he wants to do more now that we have a consistent curve on the dyno. One change with ignition timing filled in a hole in the power curve below 11K RPM. As for getting the 82+ HP we had on the first A motor, I'm beginning to see where using steel rods might be hurting the engine's power.

K@TT Race School and Track Day

I did a couple track days before the Infineon race weekend. One was the Keigwin's @ The Track race School on May 4th where I was an instructor. I was responsible for doing one class room session as well as providing 1 on 1 instruction on track with the students. My classroom topic was "Mental Preparation for Racing". Putting the material together for the presentation was educational. I've been using these techniques for years, but having to explain it to a crowd of racers forced me to think it through, and more clearly apply the techniques for myself as well.

The main point of the topic is that racing is mostly mental, and winning races is a mental exercise that starts months before the first race. We spend a lot of time working on our physical riding skill, or making our bikes faster, but many don't give mental racing the attention it needs. The topic seemed to go over well, with a few students even mentioning afterwards that my discussion opened up some doors they hadn't previously thought of. Teaching for the K@TT schools (their AFM New Rider School earlier this year, and the May 4th Racer School), has actually helped me become a better rider as well. I spend a lot of my time talking to others about riding, and this is exactly why.

Saturday Practice

At the previous Infineon race weekend (which was rained out on Sunday), we got a full day of practice on Saturday. Last time, my best lap time was 1:42. I was hoping to break into the 1:41 range this weekend, but such hopes were dashed. It was hard to get a clean lap, even in practice group 6 (fastest practice group) because of too much traffic in the corners. I got one, maybe two 1:42's all day, with mostly 1:43's and 1:44's. Regardless, the practice was good, and I spent much of the day playing with suspension setup.

I asked Phil Douglas of Aftershocks to stiffen up my forks a bit so they could handle large bumps and G-outs better. This was mostly to fix a specific corner at Thunderill, but my first time out on the new forks would be at Infineon. I was skeptical whether the change would be better or worse. They felt much stiffer now, too stiff actually. In order to compare them back to back, I left the 400cc bike's forks the old way, and put the new stiffer forks on the 450cc bike.

During Saturday practice, initially, the new forks were odd. I played with the rebound some and found a setting that made them work as well as the older forks. But, I wasn 't sure if the new forks were better, or just the same as the old forks. I seemed to have more confidence on the new forks, but without a blind test, it was hard to say. The change was made for Thunderhill anyway. I guess I will have to wait until the Thunderhill race weekend to find out which is really better.

Phil also straightened my triple clamps, and my bent forks from the Buttonwillow crash earlier this year. Phil did an excellent job of getting them straight. It isn't always recommended to straighten bent forks, but Phil said as a backup, these forks should be fine, and that's all I need them for.

Sunday Racing

Race day at last! The weather was perfect - no rain outs this time!

I was optimistic about the day. Though I hadn't broken into the 1:41's in practice yet, I was certain it would happen in Formula IV, if not 450 Superbike. It seems the races always turn a second or two faster than practice. Infineon is considered a horse power equalizer. In Formula IV, I expected this would lead to a closer race than Buttonwillow, with the underpowered Ben Welch (#163) using his 125 GP chassis 426cc single's corner speed to keep the rest of us at bay, and with my bike having it easier as well vs. the SV650's. In 450 Superbike, it meant my bike would have less of an advantage, especially at a track where Ross Wells has classically been stronger due to his years of experience, and where a hungry Tim Wheeler would have a chance to show his stuff.

I had mounted up a new front "soft" compound Michelin tire before the Saturday practice. I didn't feel any specific difference with this tire compared to the medium compound I normally use. But, I don't ride the front tire very hard. Well, the soft front was wearing pretty fast. I figured it would be OK for the first race, but I wasn't sure it would last the day. Normally, I go 3 to 4 race weekends on a medium front tire. It could also be due to the stiffer forks. I talked with Alex Florea, our resident Michelin tire guy and he pointed out that several people tore up the soft tire much faster than the medium. I decided to race 450 Superbike with this tire, and decide later if I should swap it.

450 Superbike

My first poll position! OK, so it isn't that big of a deal. AFM grids based on points in your class. Since I won Buttonwillow, I came into the Infineon round as the points leader (that is a big deal), and hence the pole holder. Regardless, this was the first time I would start an AFM event on the pole. After spending all of 2003 in the #2 spot, it was a nice change.

Next to me on the front row was:

  • Ross Wells, #32, FZR400 (450cc) - 2003 450 SB class champion
  • Tim Wheeler, #181, ZXR400
  • Paul Yoshimune, #650, VFR400 (450cc) - my pit mate and rider of the other G-Force 450cc VFR motor
  • Eddie Lee, #67 - RVF400 - riding the Lippman RVF400 this time

At Buttonwillow, I finished first with a decent lead, Ross second, and then Tim Wheeler and Paul Yoshimune with a close dice for 3rd and 4th. Tim had to come from the back of the pack for that podium spot, but this time, he was starting on the front row. I knew there would be some dicing from the four of us. Ross was down on speed this weekend. At the rained out Infineon race weekend, Ross got into the 1:42's like I did, but this weekend, his best was a high 1:43. Speaking with him late Sat. Ross felt disappointed he couldn't pull out the '42's, but I felt sure in the race he would find something. My plan was to get a good start, gap him as soon as I could and hopefully run away with it (isn't that always the plan). I didn't know what to expect from Tim Wheeler, but I mostly felt if either Tim or Paul got in front of me, I would find some way to get around them. Mostly I needed to make sure I didn't get held up behind someone while Ross ran away with it.

Further down the pack - Still absent is Richard Moore on his FZR400RRsp. Last year, Richard was the only other rider to get close to Ross and I. I wonder if he's racing at all this year. Also missing is Phil Douglas (#695, CBR400). Phil will likely not race with us this year due to knee surgery. Perhaps next year. Regardless, there is plenty of good talent coming up through the ranks.

Mark Elrod (novice, #926, RVF400) has been doing track days like there's no tomorrow, and it is really showing. I figured he would easily move into the top 10 this time. Though he was hampered by a turn 2 crash on Saturday, he got the bike back together in time for the races. Ian Gillies (#308, RVF400 - 444cc) was similarly finding new speed. He and I rode around together in Sat. practice, and I could see he was going strong. He said I pulled him along to a 1:46 which gave him grins ear to ear. Eddie Lee (#67) rode to a 5th place at Buttonwillow on a new FZR400 which he had only ridden for a couple practice sessions previously. Today, he was back on the Ken Lippman RVF400 which he rode last year, but was having issues with setup and getting comfortable on the bike. Jose (Joe) Quintanar (#79, FZR400RRsp - 2002 450 SB 2nd place) was finally back on a competitive bike. Joe and I spent some time chasing each other around two years ago fighting for top spots with Gary Jaehne in 450SB. He didn't race 450 Superbike last year. I'm glad to see him return to the class.

Other comments about riders I can think of... Mike Norman (#586, VFR400, G-Force owner and 450SB class sponsor) wasn't able to ride in Sat. practice because of bike issues, but made it for Sunday's racing. Mike quickly found new confidence due to a change in his fork setup. Greg Creech (#927), who races three different bikes (SV650, KTM Single, and CBR400RR), all three of which are legal for 450 SB, still didn't have his "real" 450 Superbike ready (the CBR400). So, he ended up racing the KTM. Chris Gallo (#643, RVF400) is joining us for his first race, though his bike actually raced at Buttonwillow. Chris is Mark Elrod's pit mate. When Mark crashed his own RVF400 at Buttonwillow, he raced Chris' bike the next day as Chris wasn't able to race that weekend. Finally, Gwyn Lewis (#751, RVF400/FZR400) showed up on her furry FZR400 (her endurance race bike). When I first saw it, I thought she finally furred the RVF. "No, no, no my FZRs are fuzzy but my Honda's not hairy...yet. My RVF motor is being torn down. Can't race it until it's rebuilt." She said. Too bad. I thought we had our first furry Honda V-four.

In all, it was 36 starters for 450 Superbike. A smaller group than normal, especially for Infineon raceway.

Let's go racing!

Paul Yoshimune Gets the Hole Shot
The 450 Superbike race was race 5, right after lunch. We were gridded as the second wave behind Open Twins. Off they went, and now it was our turn. The green flag flew, and the entire front row came off the line together except for Paul Yoshimune, who got the mother of all starts, and the hole shot. Coming out of turn 2, it was Paul, then me, and I don't know from there.

It took until the entrance of turn 6 to close the gap on Paul (he really got a good start!). I took him on the brakes into turn 7. I noticed Alex Florea (#49, RC51, Open Twins leader from Buttonwillow and the guy that supplies my Michelin tires) standing on the sidelines. Apparently he lost the front going into turn 7 while dicing with Brian Long (#71, SV1000). For me, however, things were looking good. I was in the lead, with Paul between me and Ross. I had my chance to gap the crowd before we reached the back markers. We reached the first Open Twins back markers half way through lap 2.

Each time through turns 7 and 11, I looked back to see where Paul and Ross were. I could see they were dicing back and forth, entering the t

urns as I was exiting. So I felt I was in a pretty good position. But wait, who was I forgetting? The answer to that in a moment...

As I crossed start/finish for the crossed flags (half way), my mind registered this as a white flag because I thought I had just counted 5 laps. The next time through, "where's the checker!?" I wondered. "Did I miss it?" I slowed a bit on the next lap watching others to see if they were on a cool down lap or still racing. It appeared they were still racing, but I couldn't figure out why I was messed up. Past start/finish again and still no checked flag. Then I realized my folly. We were doing 8 lap races, and the white flat I thought I saw was actually the crossed flags on lap 4. Now I was all messed up because I wasn't sure what lap I was on, and how much I had left to go.

My stupper was quickly ended when Tim Wheeler showed me a wheel up the inside of turn 2. "Whoa! That's the guy I forgot about." I was watching Paul and Ross thinking they were dicing for second place, not realizing Tim was comfortably in second and making plans to take first. There were three back markers apexing turn 2. I ran around their outside, cutting off Tim's line, and passing all three of them. What a stroke of luck. Had it not been for the back markers, Tim probably would have passed me.

Back up to speed, I worked to gap Tim again. Past start/finish once again and it really was the white flag lap. Up into turn 1, I saw a yellow flag and several more back markers. I slowed to avoid passing them as we aren't allowed to pass on a yellow. Again, Tim came up my inside going into turn 2, but he had to back off as well due to the yellow. It looked like the yellow flags were for a crash on the outside of turn 3 - a furry bike. Gwyn Lewis was hit by another bike and ran off the track. Just past the crash, I made a quick pass on a couple back markers only to be faced with yet another yellow flag going into turn 4. Right after that crash, I attempted another pass, but there was a yellow at the top of turn 6, and a back marker practically walking through the corner. Any chance at a gap on Tim was gone now.

The flag in turn 6 was for a crash exiting turn 6. I feared Tim would get a run up on me and pass me just after the incident. I passed the crash and opened it up again. Tim didn't pass me, nor did he even show me a wheel going into turn 7. He must have been equally held up by the flags and back markers. The track was clear down through 8, 9, 10 and 11, and I was able to take the win without further challenge from Tim. He wasn't far behind, though.

Ross Wells edged out Paul Yoshimune for 3rd place. With two hard fought but disappointing fourth places, Paul is very hungry for pay back at the next race. A surprising 5th was taken by Ian Gillies (congrats!). Joe Quintanar worked his way to 6th. In 7th was Mark Elrod, taking top novice honors (Good job Mark!), just edging out Craig Sanders (#327, ZXR400). Rounding out the top ten was Robert Gardiner (#798, FZR400), then Dave Norgard (#28, FZR400).

A big thumbs up goes to Tim Wheeler for beating Ross Wells (no easy feat) and coming up to give me a struggle. Also, for Paul Yoshimune for hanging with Ross, and passing back and forth several times. Both Paul and Tim have had their appetite wetted, and will likely come to Thunderhill very hungry for more. The competition in 450 Superbike is definitely heating up. I see Eric Crabtree finsihed 12th for the 2nd place novice in the class. Eddie Lee rode to a disappointing 13th. Hopefully, he'll have the Lippman RVF400 worked out for Thunderhill where he may be back up with the top 5 again.

Regarding Gwyn Lewis' crash, I understand she was transported to the hospital for head injury (precautionary), but was released later that day in good health. Alex Florea was unhappy about his crash, but otherwise OK. I don't know about any of the other crashes during my race.

I really enjoyed this race. The bike just felt fantastic, perhaps due to the suspension change, or perhaps because I'm just riding better than ever before. Ross was off the pace (doing 1:44 best) compared to his lap times from before, but there was still competition with Tim Wheeler. I also enjoyed the race because several people are finally starting to figure out their bikes (Elrod, Gillies, Yoshimune) as well as new blood (Wheeler) or new old blood (Quintanar). Two wins in a row is certainly a good start for the season. The next race is Thunderhill, classically my strongest track, but we'll see what the others have in store.

Formula IV

After the 450 Superbike race, I was concerned about the soft front tire. It was really eaten up and I was worried it might go off during the Formula IV race. Alex Florea found a practically new medium compound take off for me and mounted it up, saving me the cost of buying a brand new front, as well as setting me up with a tire that would work for the race. I'll likely stick with the medium fronts from now on.

Formula IV was scheduled as the last race of the day. I was in a state of high anticipation for the second ever running of this highly competitive class (full grid - 85 starters). During our regular races throughout the day, most the key players were turning from high 1:41 to 1:42 lap times (mostly 1:42). It was shaping up to be a very close race, with winning times in the 1:41 range for sure.

Ben Welch didn't show the best times in his Singles race (1:44), but I didn't know if he had anyone pushing him or not. In practice on Saturday, he and I diced a little, and Ben proved that when the need is there, he can stuff his little 125 GP frame into a pretty tight hole. Brian Long (#71, SV650), Yuichiro Okuhira (#609, TZR250), and I all pulled 1:42 best lap times leading races (with no one to pull us along). Michael Metcalf (#914, SV650) and Tom Dorsey (#36, SV650) reached a best of a high 1:41 in their 650 twins race. If I had to take a guess at the likely winner, I doubt I would guess right even if I had several guesses.

Unfortunately, we'll never know. A crash late in race 12 involved a severe injury, and the time it took to take care of the injured rider pushed us too close to the 6pm cut off time. AFM had to cancel the 13th and final race. Formula IV would have to wait yet again.

Weekend Conclusion

I was pretty unhappy about the cancelation of Formula IV. So much anticipation for a race, only to have it dashed again. We were all suited up, sitting in the hot pits waiting for our warm up lap when it was canceled. That was painful. But, 450 Superbike was a great race, which helped make up for it.

There are much worse things to be worried about, including the injured riders from this last weekend. Three people were transported via helicopter to the hospital this weekend (including the crash that resulted in canceling Formula IV). Worst of them was Richard Thorwaldson Sr. At 58 years old, he's one of the older members of the club, and a long time AFM racer. He sustained head injuries as well as other injuries. My heart goes out Richard, and the others and a wish for a speedy recovery. UPDATE: It is with great sadness that I must report that Richard did not recover from his injuries and passed away. I have gotten to know a lot of the AFM membership, but Richard is one person I hadn't yet met. Racing is fun for many personal reasons, but it's the people I race with that makes it most enjoyable. Many people called Richard a friend and more, and I feel he is a person I would have enjoyed meeting. Godspeed Richard.

Finally, some thanks.

  • To Mike Norman of G-Force Performance Center for his long hours of effort on my 450cc VFR engine. He loves these bikes as much as I do, and his dedication to developing the VFR/RVF400 engine is inspiring.
  • To Phil Douglas of Aftershocks for several long talks and some fixes to my suspension. I can probably attribute the 450SB win to Phil this time. The fork upgrade definitely worked. Even though I wasn't sure about it at first, I think the new forks gave me the confidence to ride like I've never ridden before.
  • To Alex Florea of AFMotorsports, and Michelin. Alex helped a lot this weekend with tire choice, as well as helping me learn how to better use the front end of a motorcycle.

Other sponsors I would like to thank include the Lockhart Phillips Team Privateer program, ZoomZoom Track Days for sponsoring Formula IV, Keigwin's @ The Track for offering me the chance to work as an instructor (which improves my own riding as well), and of course G-Force for sponsoring 450 Superbike.


Leading the race, Tim, Ross and Paul in the Background
Infineon Turn 8

© 2004 Gary Rather Photography
Official Results for all races:

dBcom Results for selected classes (complete dBcom results available at


BARF (the Bay Area Rider's Forum) has made great plans to do a series of articles, video clips, interviews and more about AFM racing this year. Below is a sampling of some articles about the Infineon race weekend. I am also including links to other press articles I find about the weekend. BARF's main race coverage can be found on their Racing page.

Last Updated: Wed, Jun 30, 2004

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