http://www.scsextra.com/specials/photocon/vote.php?groupId=14&showImage=1061
and
http://www.scsextra.com/specials/photocon/vote.php?groupId=14&showImage=1066
Click ‘vote for this photo’ on both 
Local paper ‘Santa Cruz Sentinel ~ 2008 Santa Cruz Wheels’ photo contest.
http://www.scsextra.com/specials/photocon/index.php?groupId=14
Winner gets a big color photo in the paper of course. And we could use the press to spread our three wheel religion.
~Sarah
West Coast points have been tallied from the Road America event. I’ve been bumped up to 4th place behind Oliver, and Mike’s hot on Ian’s trail. We’re both 10 points shy of 3rd overall in the standings. =D
We’ll see if we can fix that out at Reno/Fernly in two months!
~Sarah
Short Summary…
Fly in Thursday Morning
~ Set up pits in pouring rain and lighting hitting around the track, waiving metal canopy poles around with Ian and Dennis, giggling like an idiot the whole time. Go back to hotel
~ Run into liquor store when tornado sirens go off
~ Run back to hotel with beer and drink (lots)
Friday (the 13th)
~ No practice all day as there was TORNADO AND STORM damage to the race track that had to be repaired.
~ Lots of poo-talking and bench racing between all the teams all day. Got to know all the East-Coasters.
~ Crazy old farmer who’s been racing cars for years gives us laps around the track for fun and points out the ‘fast line’ using one of the Road America trucks. This was fun.
Saturday
~ Two short practice sessions where we find out they spray the surface of RA with Pam before each race… slippery is an understatement. Sarah is, “Fast and Furious Wisconsin Drift”. Very first time out out going into turn two she’s in early and hot, and now we’re out on the rumble strips sliding around, and I’m on the back laughing my ass off trying to keep it down for her. We get back out on the straight and I reach up and pat her back, letting her know I’m still with us.
~ Oliver blows a motor in practice… with 30 more minutes he would have had his spare bolted in and read to go for the race… toe to toe with Frank
~ Race goes off without a hitch, RA is a fast track, Fourth place F1 finish.
~ Frank takes the win and laps us right at the very end. We catch the checkers behind him hard on the power… confusing AHRMA who award us 2nd place (sweet). They even hand us the trophies at the awards ceremony, which we then make a little announcement about the easiest way to catch 2nd is to let the leader lap you just out of sight before the checkers and come in right behind him… We then hand the wood to the true 2nd place F1 winners.
~ Frank then flys out of Chicago that evening since he gets the page that his wife has gone into labor. We then get up to the minute SMS updates from Frank from that point out.
Sunday
~ AHRMA gives us one practice session before racing, things feel much better.
~ We find out the violent tankslappers we’ve been experiencing coming down hard on the brakes into 5 are not geometry or suspension issues but the goofball on the back setting up and hanging out for the left way too early causing a pendulum effect upsetting the entire chassis. Sadly this means no more exciting rodeo action for the race fans in turn 5 as BCR comes in fishtailing chair in the air off onto the rumbles and nearly the grass every lap.
~ With some coaching from Dennis, goofball sits center chair behind the driver for all hard braking lefts till the last possible second before turn in before getting out, and suddenly like magic everything is butter and all traces of headshake vanish. Go figure. Sarah gets her Fogarty stare back.
~ Race goes off without a hitch. Oliver’s new motor is in, he looked good in practice, and again… just hammers it. Ian waves from the tuck as they go by, Oliver swoops over tight on us as he passes on the front straight to make it look good for the crowd. =D
~ We were keeping up on the tail of the wily Brits on 007 the first two laps during the race since we knew in practice we could catch and out pace them in the morning practice. But it wasn’t meant to be, we shot our proverbial load pacing them to watch their lines and them making the pass and pulling away, burning up our reserves for the race. Rather than risk throwing it away Sarah ran her pace and we just enjoyed being out on the track, getting it loose in the corners, stretching the CSR’s legs with top speed runs, getting the chair up in the air over lefts, and enjoying the blur of the Wisconsin countryside at triple digits while trailing 007. Our last time out on the track, might as well have some fun =D
~ We get in another 4th place F1 finish, and bring the gear home intact ready for Reno/Fernley Superside/AMA in two months.
~ Frank gets a 5.5 pound girl sidecar racer, Congrats Frank… A baby on Fathers Day!
There’s lots more about Sarah’s trips onto the rumble strips, getting sideways, or hitting speeds so fast down the straights that the vacuum created behind the intake scoop with my helmet tucked behind it made it hard to suck in breath. But that’s for another time.
Needless to say, the trip to RA was a great learning experience for the both of us, and we’re happy with two 4ths in F1. I’ll never be afraid of Sarah breaking the rig loose or getting in hot or sideways, or running right out to the ragged edge of the track. This girl had my butt in the grass clipping apexes like a pro by Sunday. I’m proud of her. Thanks to the East Coast SRA for being a cool bunch of folk, and see you next year!
Road America is a Beast.
Sarah & Mike
All packed in today… Along with all our gear, toolboxes, spares, etc. 100% committed at this point. Transporter leaves tomorrow AM for Wisconsin, we fly out Thursday.
Well kiddies… it’s nearly time for Sarah and I to head to Road America. And the difference between the tracks that Sarah and I normally race on and Road America is straights and sweepers that you could land a 747 on. Fellow sidecar brethren and two-wheeled racers who have run there warn us of massive roller-coaster elevation changes, seemingly endless and wide pavement that has you pinning the throttle for what feels like days, and extremely high speed sweepers that make the top of the backside of 9 laughable.
The CSR is geared pretty short for most the tracks we run at, more grunt on the bottom end to haul my fat ass around, and get Sarah the holeshot advantage she likes to use off of the corners when she makes passes. But Road America is a different beast, a lazy blubbery object curled up in a fetal position clinging onto the back of a F1 sidecar platform in motion, tends to stay in motion.
With that in mind, I bought a new 46 tooth chain ring, a 42 tooth chain ring, and a 15, 16, and 17 tooth counter shaft sprocket.
First… Let me teach you how to do some basic math to figure out just how fast your bike will mechanically go, not counting for wind resistance or rolling resistance.
…,
1 ~ Whip out your best thin tape measure, and accurately measure in cm around the circumference of your tire. Not all tires are the same size, and tires do wear over time. So if you want to know how fast you can go -right now- take a measurement right now. In my case, 164cm on the Yokohama slick on the back of the CSR, or 1640mm.
1a ~ Convert that to Kilometers, or in other words, add a dot and two zeros. 0.00164km. Save that number, it’s important later.
2 ~ Pick a RPM, for the sake of sanity, I chose 11,000 ~ Sarah’s shift light is set to 11,500 RPM. Multiply that times 60, you get 660000 Revs Per Hour.
3 ~ Find out what your Primary Drive Ratio is, it’s in your manual, online, mine is 1.604
4 ~ Find out what your 6th gear ratio is. Mine is 29 teeth to 25 teeth or, divide 29 by 25 and you get a 1.16 ratio
5 ~ Now for some math…
Revs Per Hour 660000 divided by the primary drive ratio of 1.604 equals 411471 Revs Per Hour primary drive ~ divide that by the 6th gear ratio 1.16 equals 354716 Revs Per Hour of the counter shaft.
6 ~ Now you figure out the possible combinations of final gearing ratios you want to choose from by simple division.
6a – Final Ratio ~ counter shaft sprocket 15 / rear sprocket 42 – 2.8
6b – Final Ratio ~ counter shaft sprocket 16/ rear sprocket 42 – 2.625
6c – Final Ratio ~ counter shaft sprocket 17/ rear sprocket 42 – 2.47
6d – Final Ratio ~ counter shaft sprocket 15/ rear sprocket 46 – 3.07
6e – Final Ratio ~ counter shaft sprocket 16/ rear sprocket 46 – 2.875
6f – Final Ratio ~ counter shaft sprocket 17/ rear sprocket 46 – 2.71
7 ~ Now that you have your counter shaft to rear sprocket ratios divide your counter shaft revs per hour (354716 in my case) by your selected final ratio to figure out how many revolutions per hour of the rear wheel that particular gear ratio will give you.
7a 15/42 – 126684.2857 rph rear wheel
7b 16/42 – 135129.9047 rph rear wheel
7c 17/42 – 143609.7165 rph rear wheel
7d 15/46 – 115542.6710 rph rear wheel
7e 16/46 – 123379.4782 rph rear wheel
7f 17/46 – 130891.5129 rph rear wheel
8 ~ And once you have your Revs per Hour of the rear wheel, multiply that by your original measured KM tire circumference. In my case 0.00164km. Then convert the Kph to Mph and you’re set, you have your theoretical top speed at that given RPM (11k in my case) for that gear ratio.
8a 15/42 ~ 207.76 kph ~ 129.10 mph @ 11k RPM
8b 16/42 ~ 221.61 kph ~ 137.71 mph @ 11k RPM
8c 17/42 ~ 235.51 kph ~ 146.35 mph @ 11k RPM
8d 15/46 ~ 189.48 kph ~ 117.74 mph @ 11k RPM
8e 16/46 ~ 202.34 kph ~ 125.73 mph @ 11k RPM
8f 17/46 ~ 214.66 kph ~ 133.39 mph @ 11k RPM
…,
There are some tools that can do all this for you online with the flick of a few keys, but it’s nice to know the math to be able to do it yourself. And I like figuring things out. In my case I have an oddball rear tire size so calibration and measurement can’t be done by the preset online calculators.
Now that I had my gearing, I decided to gear as tall as I could go. 17/42 @ 146.35 at 11k RPM or hitting 160 at what I have the rev-limiter set in the translogic unit.
So I got the new gearing installed, and a new chain on. But now I needed to recalibrate the speedo, which has always been off to begin with due to the 13 inch rim on the back and oddball sprockets. For this we’ll be using a product called the “Speedo Healer”
I got in on a group buy on this two years ago, and it’s literally been sitting on my shelf ever since.
But, how do you calibrate the speedo on a stationary vehicle?
Well, the -lazy- way is to go down to the local bike shop and buy a Cateye Enduro 8 MTB speedometer for 30 bucks.
This unit allows you to enter in the circumference of your wheel (164cm) and then has a wired lead to a hall sensor that picks up the pulses from a magnet that you mount to a rotor/sprocket/etc on your wheel.
For my purposes I simply drilled and tapped one of my sprocket bolts for the magnet carrier, and secured it in place with a little epoxy just to be sure. I then just used the stock components from the kit to zip-tie the hall sensor to the swingarm in close proximity to the magnet.
Once I had the bike in gear and running, the CatEye speedo picked up changes in speed accurate down to the 0.5 intervals. I was pretty impressed.
The Speedo-Healer has a steep learning curve in terms of calibration. The directions flat out suck. They’re written by someone who has a fetish for complexity and verbosity where it is not needed. I think I found Fenor’s afterhours gig. If the guys from Speedo-Healer are reading this, please contact me, I could write clear and concise directions for this unit that fit on a matchbook cover, not the three page mess that you deliver with the product.
Needless to say it’s thankful I can count binary on one hand that I’m good with dip switch configuration hardware. Only the last three switches, 4/5/6 really matter for speedo correction, and 3 decides if your doing positive or negative adjustment. 4/5/6 equates to Ones/Tens/Hundredths of increment of adjustment in nine step adjustment intervals as determined by a pulse sequence from the LED embedded in the unit. (Think cheap ODB-II code reader) The toughest part of the whole thing once you have the swing of it is remembering that (in my case since I was correcting the speedo down) to set the speed higher you have to add less to your 4/5/6 settings because the unit is set to correct down. My magic number was 1 pulse on 4, 7 pulses on 5, and no pulses on 6. Flipping all the dip switches down once you’ve got it configured writes the settings to NVRAM, and you’re done.
I was able to throw the CSR into 6th gear and go up and down steady through the rev range and watch the stock speedo and CatEye Enduro 8 stay in exact synch with each other. The Speedo-Healer while having a clunky interface does as advertised.
The major drawback to this is of course since the pulse width modulation coming from the transmission pickup was now being changed by the Speedo-Healer my Endgear digital gear indicator was now out of wack. But luckly the Starlane unit is easy to recalibrate and takes all of 30 seconds to get back in sync with the transmission. It’s just annoying to know that I’m going to have to do that every time we change our gearing ratios.
“But Mike? How do you know you made the right gearing choice for Road America?”
Well see, I think computers are amazingly useful tools, not only for talking shit on the internet, but simulating things you do not have the resources to do in the real world. And thanks to our sponsor SimBin we’re able to do just that.
I fire up SimBin provided/modded copy of GTR2 and load up the Road America track expansion. I then load up the Radical SR3 with the 205 horsepower ‘Hayabusa’ powerplant that has been modified to have an asymmetrical chassis geometry to give it handling more in tune with a F1 sidecar.
I then plug in the first through sixth gear ratios from the 2004 CBR1000RR engine in our CSR, and start trying my available final drive ratios ‘in the simulator’ till I find a good combination of corner gearing and straight-line gearing. I set the redline on the motor to 11.5k and hit the track.
And then of course, I take it out on the track for a drive and see what it will do.