crescent 500cc

[lcp8410]

it that crescent 500cc a reedless motor? i heard it is the fastest among c racer...how could this motor make so much power...hope someone will share...

[ZUL8TR]

some Cresent history and stats

http://dickodea.com/The%20Crescent%2...es%20Story.htm

http://pfs-ware.com/RacingHistory/email.htm

http://www.screamandfly.com/showthre...-The-Super-C-s

Attached Cresent specs from 1978 APBA Insp manual

[Wagneracing06]

Rob Dixon has one

Saturday night at the campfire ring at the Franklin race this year, I had a long talk with Rob Dixon about the super C's. Apparently he inherited an Alky one with a lot extra parts both stock and pro. I think for the right amount of cash he'll part with it. If I had the money I'd buy it and put it on my restored Butts super C hydro. But I don't have the cash.
I sold my motors to Mark Storm from here in Ohio. Somehow one of them ended up in Michigan. I'll sell my boat if anyone's interested.

Rick Wagner Sr.

[optimus]

Crescent Super C stocker on Ebay, Its just worth looking as the pictures

http://www.ebay.com/itm/CRESCENT-RAC...0b4628&vxp=mtr

[rumleyfips]

Crescents were great. I saw them run agiant C loopers , Koenigs with muffler cans and Koenigs with chambers at Southbury, Conn in the late 60's. Crecsents fascinated me because they would run silenlty out front with just a bit of a whistle. The loopers shrieked and the Koenigs yelled but all the fuss didn't help them keep up. Quiet C alkys were so nice.

I think someone tried chambers on one but wasn't as fast as the standard exhaust.

Did they have a tuning pipe in the tower?

John McManus

[ZUL8TR]

Cresent exhaust

Crescents were great. I saw them run agiant C loopers , Koenigs with muffler cans and Koenigs with chambers at Southbury, Conn in the late 60's. Crecsents fascinated me because they would run silenlty out front with just a bit of a whistle. The loopers shrieked and the Koenigs yelled but all the fuss didn't help them keep up. Quiet C alkys were so nice.

I think someone tried chambers on one but wasn't as fast as the standard exhaust.

Did they have a tuning pipe in the tower?

John McManus

No pipes as far as I have read just the three cylinder internal exhaust tuning (no expansion chambers or megaphones needed) both giving a big weight advantage.

[lcp8410]

crescent 500

no expansion chambers or megaphones? is it a reedless motor just like the chainsaw?....hope someone will flash some ligth on this....

[Bob Dunlap]

Crescents

Crescents had tuning pipes in the towers. They slid in from the bottom. Several different length pipes were available for tuning. I'll try to post some pictures of them sometime.

[bh/]

-check out Dick O'Deas website;

www.dickodea.com

The Crescent Engines Story:

In 1964, I was invited to participate in the World 500cc Hydroplane Championship in Stockholm, Sweden. I was invited by a friend to drive a Crescent powered Hydroplane. The only stipulation being that I had to bring my own boat and propellers. Sid-Craft built an 11 Ft. hydroplane and shipped it to Sweden before the May 30, 1964 race.

I arrived about a week before the race and we did some testing on a small lake outside of Uppsala, Sweden. After I finished testing and feeling I had the boat going quite well, I was asked by the people of the Crescent company to let a German driver, Walter Vicer take a test run in the boat. He was used to driving a lay down hydroplane instead of a kneel down hydroplane, he was not familiar with the handling. On the 2nd or 3rd lap around the lake, he lost control of the boat and crashed into some large rocks at the end of the lake. He was quite severely injured. After looking over the damage, I felt the boat was beyond repair.

The crescent people contacted a cabinet maker in Stockholm, Sweden, and in record time he was able to repair the boat and I was able to compete in the championship race. After all the excitement, I finished 2nd in the World 500cc Championship. During talks before my return to the US, it was decided that I would be the North American distributer for Crescent Racing Engines.

The first alky engines arrived in the fall of 1964 and by 1965 the C-stock engines had started to arrive. The Super C-class was formed in APBA and competition began. After about 25 of the C-stock engines had arrived, I was advised by the factory they would no longer supply lower units or drive-shaft housings. They were kind enough to supply me the patterns and we started production of these items in the US. Approximately 25 drive shaft housings were built, 50 lower units, and we used Mercury clamp brackets to finish things off. All told, close to 50 C-stock engines were sold before Powerhead Productions had ceased and about 25 of the alky engines had been delivered in the US. The factory finally decided it was not profitable to manufacture anymore powerheads and we discontinued selling the engine.


One mystery that should be cleared up; is that the only difference between C-stock and C-alky engine was that C-alky engine had higher compression and used 3 large O’Dea built alky carburetors.


Today crescent engines have become quite collectible. A small group of Crescent owners in Sweden, still race the engines today with some small parts being made by vendors in Europe.

[bh/]

This one on e-bay is amazingly original;
-ie; -the OEM mid, that was prone to fracture,
and the 1st ed. BING carbs.
They were seen in later years with Amals, Delortos,
and Dicks own alky carb,
which , not surprisingly, strongly resemble Konig carbs

In the '60s this motor was 'state of-the art' in Europe,
where as a M30H was WWII technology.
By the '70s, a good Konig VC on sliding pipes was faster.
But, as Dick says, we never did see how far the Crescent's
development could have taken it ?

They had chrome bores, which were problematic.
-and simple piston timed 3rd ports,
which were bullet proof;
-but, with radical port timing, starting and mid range suffered.

[bh/]

-a early O'Dea add.
NB;-70#s, all up, C-Stock !
-and how much HPs ?

[lcp8410]

reed valve motor

is this a reed valve motor?

[Steve77t]

is this a reed valve motor?

NO! it is a piston Port, See Brians post about piston timed

[Wagneracing06]

No Reed valves

is this a reed valve motor?

The motor didn't have reed valves. The port timing,and the piston allowed for the transfer of fuel from the crankcase to the combustion chamber. That's why they had to have 3 carbs. I believe (If my memory is correct) one of the additional differences between the alky and the stock motor was there was an adapter mounting plate for either the Bing carburetors or Dick O'Dea's. The exhaust tuners kind of reminded me of a tulip bulb planter. I seem to remember that the stock tuners were different from the alky tuners. I had bought an Alky motor minus the gearcase, and parts from Bob Van Over. I had hoped that the tuner pipes would fit, but they didn't .
I wonder if the stock engine would have eventually broke the 100 mph straightaway record. Brad Snow's 92 MPH was never broken. Billy Simmons had a really smoking fast record breaking rig, but he scattered the engine I believe in 1973 or 1974. I seem to think he held the competition record. With the advancements in boat design and 3 and 4 blade propellers I think 100 MPH would have been a reality.
I was the only racer who had one in the midwest during the mid to late 70's. The only time I raced it stock was at the Nationals. I raced it in C-D-F Alky Hydro. (Stepped up). Back in the day we used to race and get paid prize money. I wasn't the fastest boat on the course, but definitely the stock crescent was more dependable. I always made enough money to pay for my gasoline expenses to TRORA races.
Well I guess I should get off the computer and finish packing for Constantine.

Rick SR.

[Wagneracing06]

No Reed valves

is this a reed valve motor?

The motor didn't have reed valves. The port timing,and the piston allowed for the transfer of fuel from the crankcase to the combustion chamber. That's why they had to have 3 carbs. I believe (If my memory is correct) one of the additional differences between the alky and the stock motor was there was an adapter mounting plate for either the Bing carburetors or Dick O'Dea's. The exhaust tuners kind of reminded me of a tulip bulb planter. I seem to remember that the stock tuners were different from the alky tuners. I had bought a Alky motor minus the gearcase, and parts from Bob Van Over. I had hoped that the tuner pipes would fit, but they didn't .
I wonder if the stock engine would have eventually broke the 100 mph straightaway record. Brad Snow's 92 MPH was never broken. Billy Simmons had a really smoking fast record breaking rig, but he scattered the engine I believe in 1973 or 1974. I seem to think he held the competition record. With the advancements in boat design and 3 and 4 blade propellers I think 100 MPH would have been a reality.
I was the only racer who had one in the midwest during the mid to late 70's. The only time I raced it stock was at the Nationals. I raced it in C-D-F Alky Hydro. (Stepped up). Back in the day we used to race and get paid prize money. I wasn't the fastest boat on the course, but definitely the stock crescent was more dependable. I always made enough money to pay for my gasoline expenses to TRORA races.
Well I guess I should get off the computer and finish packing for Constantine.

Rick SR.