Wow, miss a few days - I miss a lot around here. MC-1 bad for a total loss system. Got to go to a digital MSD box. It will run the bike at a far lower voltage than the MC-1 will. How do I know? Prostar race; second round; bike is normal until 400'. Wouldn't rev over 5 grand. Lost race. MC-1 with 10.9 volts. Went to see MSD trailer at Indy Nationals later that year. Found out that the MC-1 couldn't handle the low voltage that my battery had dropped to. The digital boxes that MSD had (and tested in front of me) would run at least 1.5 volts lower than the analog MC-1. I was running a Yuasa 16 volt battery with 5 passes on it from fully charged. If you've got an aftermarket ignition that has a wire for electronic tach, you'll be ahead of the game. The stock mechanical tach of the 750 series will work with the automatics; it's just not that accurate. The mechanical tachs will repeat accurately, they just may be a few hundred rpm off. For drag racing, the only critical rpm is the redline. I use MSD with a redline chip to ensure that no valves get introduced to any of my rotating pistons. You use the tach for the one shift. I've used the mechanical tach for shifting with a .001 second variation between back to back quarter mile passes.
Yes the bike revs faster without the charging system. No, the street bikes aren't required to show a working headlight or turn signals. Yes, a lot of racers use a switched led as the tail light. Those are required in case you run off of the end of the track, beyond the track lighting. The people in the tower want to know if you are off of the track safely or not. Stock batteries weigh a lot. Most serious racers have gone to the rechargeable drill batteries on their bikes. Custom mounts for the batteries are available. They change out in seconds. Haven't tried to restart a bike with them. The only time that you would be required to restart a bike is if you are shut down coming up to the starting line. Usually that happens when there is a problem at the far end of the track or the timing system has a problem.
Flashing the converter is being thought of wrong. If you apply the rear brake and give the bike gas, you are loading the motor against the converter slippage. To "flash" the converter, you would bring the rpms up just as you leave the starting line. Without a load on the converter, it will slip more briefly. This will allow you to leave the line at a higher rpm. (flashes higher) The problem with flashing the converter is that you can't do it consistantly. Sam is doing bracket racing. A couple of hundredths quicker inconsistently isn't what he wants. The load of brake is a very effective rev limiter for the torque converter. Most drag racing bracket street classes don't allow a launch rev limiter. The Hondamatic has a natural one until you get very high horsepower. Every torque converter has a stall speed. That means that if you can rev the motor to that rpm against a brake, the bike will stall/stop running. The load that the torque converter applies to the motor keeps the rpms below the stall speed for most circumstances. My 10 second Hondamatic uses a two step to keep the rpms at a fixed point below the stall speed for my launches. Sam's motor doesn't make quite that much horsepower... Remember that when you dyno test a Hondamatic, you're losing at least 20% of the horsepower through the slippage of the torque converter. The forced slippage of the converter causes a dramatic rise in the temperature of the oil in the bike/converter. That's why you can't load the converter for very long on the starting line. The higher oil temperatures thin out the oil's viscosity and slows the bike. You have to use a good external oil cooler to try to control the oil temperature fluctuations. Consistency racing is reducing all variations as much as possible.
Transmissions - my favorite fantasy. Two wide gears control the Hondamatic. Newer bikes use thinner/stronger gears. There is physically room enough to fit a 4 speed into the motor. (say from a newer 600cc sport bike) Since you'll never see over 100 horsepower at the gears (20+% loss in the converter) the strength isn't an issue. The custom shafts for the gears; the shift forks and mounts for the two additional gears; the shift drum to control all of that - well I just feel that the cost is rather high.....! IF you're going to do all of that, why would you keep the two clutch packs and shafts between the converter and the tranny? The clutch packs are to cushion the shifts/launches. Another variable that isn't desired in racing. I'd like to see a sprocket/chain arrangement to bypass the clutches and a complete transmission module from another bike used. That has some machining issues and a big strength issue when welding to the stock case half. Maybe it can be done. I know that someday I will try it. If anybody is ahead of me, please post pictures!!!!
Hondamatic
