baz
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Looks like the one he extended the cylinder head fins on ?
Jim Comstock's race bike, pictures!
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Schwany
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This has all probably been hashed over many times in the past, so I apologize sort of.
Is the motor a stressed member in a trellised frame on the last version built (shown in post #4)? So... Not very close to the same as the bike frame pictured in post #15 I was babbling about.
The gearbox looks unique based on where the clutch is in relationship to the mainshaft and gearbox sprocket.
Chris
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Fast Eddie
Well I fabbed the housing from aluminum plate and machined end plates from billet 7075. The shafts, shift forks and drum are from a 495 KTM. I made the gears from 9310VAR. First gear was very low and only used for launch. It was back-cut like a drag trans so all it took to shift to second was a light push on the shifter. Second would be engaged before first was disengaged and first would be pushed out of engagement when the shaft over-ran first. Once you were in second then a spring loaded pin would would prevent neutral or first from being selected without pushing in on the shift shaft. There was no engine braking in first as the back-cut would just push the trans to neutral if you let off the throttle.
I made up gears to give 2 ratio choices for second and third and three choices for fourth. All shafts were supported on roller bearings. Ratio changes were simple as the right cover was o-ringed and all you had to do was lean the bike to the left to keep the oil in and remove the cover to swap gears.
It was all built on a manual Bridgeport. I turned the gear blanks on a lathe and sent them to Co. Springs to an outfit with a gear hob to cut the teeth. Then to Kansas City for hardening. Then to Iowa to have the internal splines cut with an EDM after hardening.
I raced with it for 10 years and it was unbreakable. It was always good for the holeshot. Jim
Well I fabbed the housing from aluminum plate and machined end plates from billet 7075. The shafts, shift forks and drum are from a 495 KTM. I made the gears from 9310VAR. First gear was very low and only used for launch. It was back-cut like a drag trans so all it took to shift to second was a light push on the shifter. Second would be engaged before first was disengaged and first would be pushed out of engagement when the shaft over-ran first. Once you were in second then a spring loaded pin would would prevent neutral or first from being selected without pushing in on the shift shaft. There was no engine braking in first as the back-cut would just push the trans to neutral if you let off the throttle.
I made up gears to give 2 ratio choices for second and third and three choices for fourth. All shafts were supported on roller bearings. Ratio changes were simple as the right cover was o-ringed and all you had to do was lean the bike to the left to keep the oil in and remove the cover to swap gears.
It was all built on a manual Bridgeport. I turned the gear blanks on a lathe and sent them to Co. Springs to an outfit with a gear hob to cut the teeth. Then to Kansas City for hardening. Then to Iowa to have the internal splines cut with an EDM after hardening.
I raced with it for 10 years and it was unbreakable. It was always good for the holeshot. Jim
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