Kawi2strokes.com Forum

Altered stud locations, we all love 'em. True racing story.

1972, Suzuki TR750 had special cast cylinder and head, NOT derived from a street bike casting, as we did on the H2R's. Jody Nicholas won some races that year, (great guy, Jody) and, our fearless leader, Hansen, found the 3 head bolts that were moved in the specialty castings on the 'Zook. He made a real issue of it, being a mucky-muck in then AMA at the time. So, the competition rules committee went ahead and made a rules change, that ALL racing cylinder and head bolt/stud configurations/spacing, WOULD conform to stock street bike patterns, preferably, using stock street bike cylinders/heads as the basis of the racing cylinders/heads.

So, we got caught also, from Big Mouth Hansen being greedy in wanting to win races by committee, instead of riding them to win. It was at the very last of 1972, we began refering to anything that went wrong, as "Hansen-ing", as in "The left cylinder seized", "Nope, it was yet another radical case of 'Hansen-ing'".

This is why the GT750 evolved from a somewhat slug in its early years, to a hot rod in its later ones. WE got to swap left for right, right for left, no outer fins, heads sticking out past the lack of cylinder fins, and, performance dropping way off after a couple of laps, because the giant heat pump in the frame slowed way down. The 'Zook's just got faster, and faster, and, stayed cool.

Remember, the Honda's had a race kit to convert a street bike/engine to racer, Yamaha did a completely different bike in the TA/TZ, so, they were open to just about anything, but we, and the Suzuki guys, came up short in our ability to build specialty stuff for real fast performance.

I can believe it, the stock Suki cylinder bank has to weight 40 lbs. or more.......

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Twist the throttle, tilt the horizon, and have a great time. What triples are all about...........

It belongs to a mate of mine, he wants it and its location to remain relatively unknown until he gets it finished . The only pic of the motor I have is of the front corner..... looks like its real to me....

Graham

Hi Graham, Thats an A1RA eng. in the pic. from what I can see., they had the bosses on the cylinders while the A7RA's had the bosses on the heads, and couldn't see from the pic if it had the dry clutch, if not than its an A1R eng and not an A1RA. Nice bike and project but most likely an A1RA not A7RA

Yep agree on the 250, the rotary cover is mag, which would make it a RA.

I'm wondering if it isn't a 1970 A1RA(or a later 69), in that the frame is slightly different from the early 69 that we got. We recieved frame part number 01 & 02, which were A7RA's and frame part number's 03; 04; 05; 08; 09; & 010 which were A1RA's. It make sense that if Kawa. made any others that some would be sent to europe 1st(possibly Frame part number's 06 & 07), then Australia later. I think their season starts in winter or late fall.

I had a set of 1972 H2-R cylinders and heads (no longer have them, traded them for KR750 parts with Kevin Cameron) and although the heads were definitely modified street parts, the cylinders weren't. They were special castings with bridged inlet and exhaust ports, and wider stud spacing than street cylinders.
I often wondered whether it would have been legal to weld the fins which had been cut off the 73 LH and RH cylinders back on to the other side. After all, it would be using stock material on the same stock casting and not adding extra material.
And Yamaha got away with cheating with first the TZ350 in 1973 and a year later with the TZ750. There was no watercooled RD350 (or R5) at the time, and as for a street TZ750....... Those two were far worse than either the 1972 Suzuki or 1972 H2-R.

I have the serial number on that frame it is above 10. The frame change looks like a factory experiment and not a modification.

Oh I believe some of the other bikes with frames below 10 also came into the US, as spares. #6 and #7 are/were in the US.

Now there was definitely one in Europe after Daytona in 69, perhaps Simmons took his bike back.

There is one H1 cyl head in my stock with non-standard studspacing. Always thought it was a poor copy from some nitwit.
Great job restoring that bike! And tracing back its history.
Brings back great memories about the time when racing was praticed by fanatics, nutters, plain smart guys, weirdoos and idiots all at the same time.

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Speed is what’s life about.

I looked up the 1969 FIM Grand Prix motorcycle season and it seems that Dave Simmonds did race a Kawasaki in the 125cc class where he won the championship, and raced in the 250cc class(A1RA) and also the 350 class (A7RA). Most likely took his Daytona A1RA and possibly A7RA eng part number 002 or #003 back w/ him. He was the only Kawa rider in the 350 class and 1 of 2 or 3 in the 250 class.