4 stroke or 2 stroke outboards

Tintin

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Rd 400's were good fun, but I've never heard anything better than my ( 4 stroke obviously ) Z650C3 with piper 4:1, + high lift cam & bell mouths; went and sounded absolutely wonderful, dangerously intoxicating !

My rd125 ( a long time ago) regularly put me on my ass as I accelerated away from traffic lights when working as a courier in London village. My 90hp 2-stroke mariner is much the same on my rib. A four stroke just can't compare IMHO
 

Laurie

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My rd125 ( a long time ago) regularly put me on my ass as I accelerated away from traffic lights when working as a courier in London village. My 90hp 2-stroke mariner is much the same on my rib. A four stroke just can't compare IMHO

A Yam strokers Owners Group sub thread..........?:D
Yow, mine was a RD 200.........Yooooow!:eek:

(Now get that 2 stroke outboard and be done with it!!;))
 

rotrax

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Rd 400's were good fun, but I've never heard anything better than my ( 4 stroke obviously ) Z650C3 with piper 4:1, + high lift cam & bell mouths; went and sounded absolutely wonderful, dangerously intoxicating !

Hi, in 1978 I had a P&M Formula 1 chassis built to take a Z650 engine. The engine went to LEDAR where the late Leon Moss tweaked it to over 100bhp. This was not a guess, the LEDAR Heenan and Froude dynomometer gave this figure at 10,750 RPM. It was too narrow in the power band for the wide ratio gearbox which made it hard to ride so Leon lowered the compression a little and altered the cams and ignition. This gave 96 BHP at 10,000 RPM. It was the fastest bike in the 1978 MGP races in the IOM and did over 150MPH on the drop down to Brandish. With its tuned length header pipes-22 inches- and big bore straight through pipe it sounded wonderful. Unfortunatly the bike was better than me and I finished well down the field. I can still remember the howl at 11,000 revs on the high gear it pulled in top down that hill-I'll never forget it thats for sure!
 

Seajet

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Rotrax,

thanks, very interesting; I always had the impression my Z650 had been raced, presumably in a minor way, hard shocks & forks as well as the minor engine mods.

You're a braver man than me !

KawasakiZ650C3.jpg
 
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clyst

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My rd125 ( a long time ago) regularly put me on my ass as I accelerated away from traffic lights when working as a courier in London village. My 90hp 2-stroke mariner is much the same on my rib. A four stroke just can't compare IMHO



Heavy on fuel but lovely with a drop of "R". had one for years !!
 

rotrax

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Rotrax,

thanks, very interesting; I always had the impression my Z650 had been raced, presumably in a minor way, hard shocks & forks as well as the minor engine mods.

You're a braver man than me !

KawasakiZ650C3.jpg

Nice looking bike- First Mate had a pretty stock Z650 B1 a few years ago-she really liked it. During the mid seventies I worked for the Kawasaki Importers, KMUK, at their Slough headquarters. I had two new Kawasaki's every year as staff bikes, the first was a Z650 B1 in candy apple red. In case you were unaware Kawasaki held the world 24 hour speed record for many years with the Z650 at over 120mph average speed. Suzuki broke it with the first GSX750, a new generation motorcycle. They did it in secret as if they had failed to take the record the adverse publicity would have been detrimental. As it was they did not break it by a significant amount considering the advanced spec. of the GSX Suzuki. In my view the Z650 range were just about perfect motorcycles. I am glad you enjoyed yours.
 

PeterR

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I used to use a 4Hp 2 Stroke Mariner on my Sonata. When after many years of use it broke down I purchased a new Mariner 4 Hp 4 Stroke. Although the later was quieter on a long run with less vibration, for general use it was just too heavy and too cumbersome to transport because it could only be layed down one way. I repaired the 2 stroke and the 4 stroke is still sitting virtually unused in my garage.
 
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