Classic simultaneous torque hit wheelspin/wheelie

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From 'The Motorcycle World' by P.Schilling 1974 P.145;
"The Kawasaki 750, another 3cyl 2-stroke machine, had performance so devastating it could humble all other motorcycles. Neither comfortable nor graceful in cornering the 750 Kawasaki could still best other machines point-to-point over winding roads, thanks to its tremendous accelerative & decelelrative capabilities. The 750 Kawasaki represented the end point of hot-rod motorcycles...a raw, viseral performer..."
 
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I rode a 82' 490 Maico when I was younger, and my cousin had a similar vintage Yz490. Both bikes would run out of steam once they got up to around 100mph at the top of their gearing, they had to be kept in peak torque.
The Maico that year had no reed valves like the YZ did, and so the YZ was nicer to ride slowly through the woods, but the Maico would just barely out-pull it in all-out acceleration. I think the Maico had about the same power as an 850 Commando, but was a few hundred pounds lighter, which of course helped a lot.
After 1982 the Maico got a re-make, getting rid of the old chain primary and it also got reed valves like the YZ. I rode one of these later Maicos also and they were more useable than the earlier ones.

Kevin Cameron's story in his book Top Dead Center about how he built and raced his H2R is so beautiful it will make you cry.

As far as the Norton goes, it is just a very poor engine design that happens to have a good cylinder head, which means when it is tweaked to burn as bright as a 490 Maico or Kawasaki H2R it is going to burn half as long at best......
 
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beng said:
As far as the Norton goes, it is just a very poor engine design that happens to have a good cylinder head, which means when it is tweaked to burn as bright as a 490 Maico or Kawasaki H2R it is going to burn half as long at best......
+1

Probably as concise a summary as one could get.
 
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Jeeeze guys, you`re being a bit tough aint ya, for what started out as a workman-like but fairly cheap to produce [compared to 'cammys' or Velocettes & the like] 500 to accomodate massive increases in out put & keep pace with the new-era superbikes wasn`t a bad effort...time between overhaul/power setting survey time?
 
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Dances with Shrapnel said:
beng said:
As far as the Norton goes, it is just a very poor engine design that happens to have a good cylinder head, which means when it is tweaked to burn as bright as a 490 Maico or Kawasaki H2R it is going to burn half as long at best......
+1

Probably as concise a summary as one could get.

Not that thats necessarilly a problem , theres ways and means .



Theres even a chance one had a crank from the highest grade materials manufactured , in the mid sixties. Amougst other components ,
 
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One for Hobot .



We are sadly underrepresented under ' Norton Wheelie pictures ' on google , so all please post yours .
 
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Did you miss the part in the article where it mentions the number of runs the bottom ends are good for? a couple of minutes in total? effects of exotic oxidising fuels on bearing materials?
& Matt, no evasion here, were your nitro-methane powered mills Nortons or ...gulp...2-strokes..L.O.L.
 
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According to this ,

Exhaust Timing

Variable according to track (E.O. 81 – 86 degrees ATDC)

Transfer Timing

Variable according to track (T.O. 58 – 65 degrees BBDC)

Inlet Timing

Variable according to track (I.O. 75 – 84 degrees BTDC)

The ring ding dingles pistons only doing anything for less than half of its rotation also ( the top 172 degrees being sealed or the chamber shut )
not allowing for phaseing affects of tuned pipes .

Also the long stroke commando has better time to make full use of the combustion processes , therefore utiliseing the fuel to good effect .
Rather than accostics.
Ringle ding rattle clatter .. ding ding pop crack sizzle screech . Etc .

The point above regarding FUEL INJECTION rather than Dope .
 
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I recall seeing Ginger Molloy [Kiwi privateer 1970 G.P. 500 championship runner-up to Ago on the factory M.V.]
roll up to Meremere dragstrip on his H2R roadracer, to the jeers of the hot rod crowd, but the 10.35 @ 135mph run he did [in full roadrace trim] shut them up. Hot Rod [N.Z.] magazine were so impressed they even put a shot of him doing it in their mag..
 
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J.A.W. said:
Did you miss the part in the article where it mentions the number of runs the bottom ends are good for? a couple of minutes in total? effects of exotic oxidising fuels on bearing materials?
& Matt, no evasion here, were your nitro-methane powered mills Nortons or ...gulp...2-strokes..L.O.L.

No . THAt was SPACE SHIPS !

They seemed to not have that bother with this one . Why , it even mentions a Anual service duration .



Note , C'do Vs kwickersaki , Hes waiting till hes off the line befor activateing the NoS . :p :lol: :D
 
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From Cycle Australia mag: March/April `73, P 33;
"We called the Mach IV the quickest production bike in the world, because, even with the advent of the Kawasaki 900, we believe it is."
 
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I did not remember this scene....Funny 'cause my first fall off my H2(s) was exactly the same way... wanted to impress a GF and accelerated like a maniac while taking off and turning... CDI did nor resist: the fall was on the left and it crashed 2 of the 3 triggers... expensive at 18 years old...
Philippe
 
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Ditto for me, same scenario, same outcome, but on right hand side, only scrapes, bike still ridable, I blame the drugs, or society, or was it that bloody Continental back tyre..
 
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From Motor Cycle [British mag] 10 Nov `71; H2 :1st Impression;
"Unlike so many high performance 2-stroke engines, the Kawasaki 750 produces plenty of power at lowish engine revs, & for normal fast riding, wide open throttle openings in the lower gears are unnecessary. The powerful torque made it easy to lift the front wheel high in the air - & keep it there - if you had the skill!"
 
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