Way cool, classic kneel down motor! Mark75??

This is from before my time but I remember the name.

Hopefully Sam will see this and fill in the blanks.

Guessing it to be from the Pro ranks, probably '60's era.
I love motor builders who think outside the box and the Pro classes only motor restriction is displacement limits.
Youd see a crank case from one motor grafted to cylinders to another.

In my racing era, we had a local guy that was a Yamaha dealer and raced in the 500cc (30 cu in) Pro Hydro class.
He took four YZ 125 jugs and grafted them to someone elses crankcase and broke every record there was in that class!
He had a 13' 3 point hydro running in the 120's in the '80's!

Anyhow, this is an example of that thinking, no rules, same class, 20 yrs earlier.

We think we're cool w/a V-6 making big power by screwing different pc's together.
Go to a Pro O/B race and check out some of the thinking in the pits.
You'll be blown away.

https://www.ebay.com/itm/Vintage-Rot...r/283372747884

This your Yamaha?

Was 30 yrs ago and wouldn’t know it if I saw it.

I think the creators name was Kay Harrison.
I think had four separate, sliding chambers.
Are those just manifolds for chambers on yours or megaphones??

Quote:

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Originally Posted by largecar91

This your Yamaha?

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Quote:

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Originally Posted by Instigator

This is from before my time but I remember the name.

Hopefully Sam will see this and fill in the blanks.

Guessing it to be from the Pro ranks, probably '60's era.
I love motor builders who think outside the box and the Pro classes only motor restriction is displacement limits.
Youd see a crank case from one motor grafted to cylinders to another.

In my racing era, we had a local guy that was a Yamaha dealer and raced in the 500cc (30 cu in) Pro Hydro class.
He took four YZ 125 jugs and grafted them to someone elses crankcase and broke every record there was in that class!
He had a 13' 3 point hydro running in the 120's in the '80's!

Anyhow, this is an example of that thinking, no rules, same class, 20 yrs earlier.

We think we're cool w/a V-6 making big power by screwing different pc's together.
Go to a Pro O/B race and check out some of the thinking in the pits.
You'll be blown away.

https://www.ebay.com/itm/Vintage-Rot...r/283372747884

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This is just 1950's aftermarket powerhead based exactly on 1930's Johnson. It was better than its 1930's predecessors, but was almost instantly outclassed by the more modern Anzani and Konig race motors. Very short lifespan.


Not Harrison, John Toperhanian's "Yamarude" : https://www.mecum.com/lots/RM0518-34...y-motor-stand/

Some other guys put Yamaha jugs on other crankcases later ... 1970's I'll have to think of who those guys were

Before Mr. Hallum passed away he sent over this photo.

Attachment 430790

Interesting.
It does look like an old OMC but I don’t remember them being rotary valve.

On Harrison, I’ll ck w/a friend.
We just talked about that motor. He helped him.
They rigged the 500cc hydro that set the kilo record at 131.
He was a local guy to me and my friend and I remember that motor.

Maybe not the first and certainly not the only.
Thats what made Pro, Pro.
Again, this would have been in the ‘80’s.

Greg, way cool post.
A two banger at a 100 is amazing, especially back then.
Notice name of driver.
Walin set many, many kilo records.

As a Evinrude guy I'm not surprised you know about Gerry. Left this earth way way too young.

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Originally Posted by Greg G

As a Evinrude guy I'm not surprised you know about Gerry. Left this earth way way too young.

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Yep.

And in a very sad way.

With all thems hot pipes Thermal drive. No prop needed...HeeHee. I was racing back in 1975 era and the expansion pipes were just coming into play. Some neat stuff showing up in the Mod classes back then.That old Hubble stacker ? was that one of the motors sold at that auction? Nice door stop, work of art.

My x racing pal confirms, Kay Harrison, in Ohio, did build am opposed four, 500cc Pro motor, using four YZ 125 jugs.
And broke every record there was.

Heres a couple 500cc Koenigs that my x boss built and raced.
I worked for/built boats for/raced for him about ‘1980.

Tim Butts and his famous Butts Aerowings.
Set/held every record through most of ‘70’s through early ‘80’s.

Quote:

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Originally Posted by Instigator

Interesting.
It does look like an old OMC but I don’t remember them being rotary valve.

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Yes, the 1930's Johnsons were definitely rotary valve; not only the racers but fishing versions of similar motors.

In the '80's there were a bunch of motorcycle cylindered PRO's. I think Mike Schmidt made a couple too. One was a 250 made from a pair of 125's.

The 4 pipe motor is a 1000cc Konig; 2 500's back to back. This particular one was Marshall Grant's motor. At least one other, maybe 2 more came to the US. It was a standard motor in the Konig racing catalog.

Two pipe Vs four pipe depends on manifolds too.
One into one or two into one.

I remember four pipe, 500cc 4 cylinders.
I think some of the Yamatos that were replacing the aging Koenigs maybe.

BTW, I saw one of the 1000cc, 8 cylinder at a race in Fla when we were down there.
Never saw it run though.

This is the effort that my friends were involved in.
Sean McKean's 1100cc, 131 Kilo record.
Love this shot.