100 HP 920cc motor

jseng1

jseng1

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Andy Cox and Herb Becker have recently achieved 100 HP at the Rear wheel on gas with big valves and stepped exhaust, longer rods, lightweight pistons and sifton 480/JS4 cam. Andy weighs 240 lbs and has turned 154mph.

100 HP 920cc motor


100 HP 920cc motor
 
Last edited:
Fast Eddie said:
Looks very lonely heading off into the whiteness like that !
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Indeed... Off into the unknown. I would imagine that 4 miles is a ride on the hairy edge. I'd need a gonads upgrade to attempt it. ;)

I like Herb's approach to making HP. Bigger works on the intake side if you know what your are doing, and he does. A bit way too much for a street ride, but definitely getting the job done in a long straight line.
 
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grandpaul said:
It sure was fun for me. I just did one pass, because I still had 6 races left in the season, and my gearing was NOT for top speed.

You never even SEEM to get closer to the floating mountain, it's W-A-Y out there...
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Sounds fun for certain. It would probably register as fun if I was 30 years old again. ha

I was thinking a Bonneville salt flats LSR event should be on my bucket list, but only as a spectator.
 
Schwany said:
Sounds fun for certain. It would probably register as fun if I was 30 years old again. ha

I was thinking a Bonneville salt flats LSR event should be on my bucket list, but only as a spectator.
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I was 51 years old when I ran down the salt. I'd do it again tomorrow (if I still fit into my leathers)
 
gpzkat said:
That seems to be very good speed for the HP, must be his aerodynamic physique! The power needs for going 10, 20, 30 MPH faster get ridiculous.
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A few riders seem to spend an inordinate amount of money trying to squeeze fractional horsepower out of an already tapped engine, instead of LOSING A FEW POUNDS OF EXCESS BODY WEIGHT.

"Add Lightness, add speed"
 
acotrel said:
Power in a straight line does not mean much. In most applications, that circumstance does not exist. Generally speaking - faster around the corners means faster down the straights, so good smooth power delivery and handling are at a premium. If you are 10 mph faster as you enter a straight it takes a lot of power in the other guy's bike for him to pass you before you reach the end of the straight. The bike which Peter Williams raced prior to Nortons was the Tom Arter Matchless 'Wagon Wheels'. That is where the geometry for the first Commando came from. With that much trail, a tank-slapper is very easy to get into. I do not think road-going Commandos ever had hydraulic steering dampers. The first Commandos crashed a few times until the trail was reduced by altering the fork yokes. You guys did not believe me when I told you that the way to get out of a full-on tank-slapper is to grab the tank and wait. If you fight it, you die. When it happens, you need a sense of humour - it looks really horrible.

ibb.co

Arter 1Main jpg hosted at ImgBB

Image Arter 1Main jpg hosted on ImgBB
ibb.co ibb.co
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Fark here we go again, what's that got to do with the salt flats Al, no corners there just one long straight and hold on with the throttle opened right up and if your bike is built right no fu cking tank slappers.
 

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