Thanks for the website Vibrac, there are some really nice bikes there.I have ordered a 30mm and 40mm belt drive off Bob Newby too. Cheers brt650
Who's Vincent/Hrd has the most power?
- Thread starter Brian Thompson
- Start date
That bike has been built. See http://www.badweatherbikers.com/buell/messages/32777/701153.html
I am building a special using early Rapide cases with Terry Prince 92mm topend and 92mm crank w/30mm drive side mainshaft. Cams are MK5. I also have a Quaife/Sertes 5-speed and Newby 40mm beltdrive. It is going into a 2005 999S Ducati frame with a 916 single sided swingarm. Rear wheel is 5.5 inch wide. I had to offset the engine as the widest wheel that will fit with the engine centered is 4.5 inches and required a 520 chain.
I just got the stock Terry Prince heads back from being on a flowbench at a local NASCAR engine builder. He said I should get 44hp/cylinder with the MK5 cams. He pointed out a couple of areas where the flow could be improved and I am going to do it and take the heads back to him for a second flowbench session.
I am also running a Grosset starter and BT-H magneto set up for dual plugs w/30 degrees of advance. This gives me a short advance needed for the Grosset starter. I plan on holding down the kill switch, pushing the starter button and when the engine is up to speed, releasing the kill switch. I am not going to use the stock valve lister setup.
Squish band is set at .050 in and I am using valves from Vincent Parts Germany. Valves are waisted below the buide and have thinner heads to give lower weight. Lower weight is needed because the MK5 cams peak out a 6800-7000rpms.
Initiall cargs are 37mm Keihin FCRs but I also have a pair of 41mm that will need new intake manifolds before I give them a try.
John Mead
I just got the stock Terry Prince heads back from being on a flowbench at a local NASCAR engine builder. He said I should get 44hp/cylinder with the MK5 cams. He pointed out a couple of areas where the flow could be improved and I am going to do it and take the heads back to him for a second flowbench session.
I am also running a Grosset starter and BT-H magneto set up for dual plugs w/30 degrees of advance. This gives me a short advance needed for the Grosset starter. I plan on holding down the kill switch, pushing the starter button and when the engine is up to speed, releasing the kill switch. I am not going to use the stock valve lister setup.
Squish band is set at .050 in and I am using valves from Vincent Parts Germany. Valves are waisted below the buide and have thinner heads to give lower weight. Lower weight is needed because the MK5 cams peak out a 6800-7000rpms.
Initiall cargs are 37mm Keihin FCRs but I also have a pair of 41mm that will need new intake manifolds before I give them a try.
John Mead
John, was that estimate of 44hp per cylinder at crank or rear wheel? Have you measured the C.R.?
Glen
Glen
;-)John, with that wide rear wheel on there I must inform you that you are joining the ranks of the uninformed!
Glen
Glen
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Hello John,
I like the idea of the 916 swing arm as it can be inverted to drive out the right side. Do you have any photo's yet of the frame setting up? And will you be registering this for the road?
I was thinking about Dellorto Pumper carbs?
There are 2 version's of Terry's top end kits. Early and late. I have a set of both. 92 mm kits. The second set has shorter liners and lighter piston's. Also the sealing area on the liner is a different size.
Cheers
brt650
I like the idea of the 916 swing arm as it can be inverted to drive out the right side. Do you have any photo's yet of the frame setting up? And will you be registering this for the road?
I was thinking about Dellorto Pumper carbs?
There are 2 version's of Terry's top end kits. Early and late. I have a set of both. 92 mm kits. The second set has shorter liners and lighter piston's. Also the sealing area on the liner is a different size.
Cheers
brt650
It is the only Ducati single sided swingarm that can be easily modified to put the drive on the right side. I had a machinist machine a 1/8 inch deep rectangle into the bottom of the swingarm directly below the stock shock/link attachment. He had a piece of 6061 that fit into the rectangle and I had it welded up. He then machined the slots for the shock and strut and machined for the special bolt and nut that attaches the shock and strut to the swingarm. After fitting it to the 999 frame he machined off the old attachments.
It is already registered for the street as a 1947 HRD. I checked with the club to see if anyone had the frame pieces for my engine and found out that no one did. So I welded up the Ducati frame number and stamped the frame with the corresponding Vincent frame number. Got a title from New Hampshire, over the internet, and Bob's your uncle. All I will have to do is get it inspected when finished.
The 44hp/cylinder numbers came from the software that Superflow provides with their flow benches. The engine guy has a SF600 which is for medium to large bore engines. He had previously done a pair of 90mm VW heads so he had an adapter that fit the Terry Prince heads.
How can I tell if I have the early or later 92mm topends? The pistons were made by CP in California and Terry said that they weighed less than stock pistons.
John Mead
It is already registered for the street as a 1947 HRD. I checked with the club to see if anyone had the frame pieces for my engine and found out that no one did. So I welded up the Ducati frame number and stamped the frame with the corresponding Vincent frame number. Got a title from New Hampshire, over the internet, and Bob's your uncle. All I will have to do is get it inspected when finished.
The 44hp/cylinder numbers came from the software that Superflow provides with their flow benches. The engine guy has a SF600 which is for medium to large bore engines. He had previously done a pair of 90mm VW heads so he had an adapter that fit the Terry Prince heads.
How can I tell if I have the early or later 92mm topends? The pistons were made by CP in California and Terry said that they weighed less than stock pistons.
John Mead
I believe there are several versions of Terry's kits. At one time the inlet ports were 35 mm, but on the kits I have the inlet has been opened to 38 mm. The inlet stubs, which Rodney Brown tells me are his product, are 35mm and will need to be opened up to match the ports. The inlet stubs probably date back to the TPV vincent of the80s.
At the time I ordered these kits Terry was waiting for flow testing results and planned to incorporate that info into the design.
I suspect that every flow tester /tuner has a different idea about ideal port shape/size.
My thought is that these heads have been shown to work very well as is, maybe try them first before making changesl? That way at least you could establish a baseline dyno reading and see whether the changes add or subtract from the result, not just the ultimate number, which isn't all that important in a roadbike, but all along the graph..
At the time I ordered these kits Terry was waiting for flow testing results and planned to incorporate that info into the design.
I suspect that every flow tester /tuner has a different idea about ideal port shape/size.
My thought is that these heads have been shown to work very well as is, maybe try them first before making changesl? That way at least you could establish a baseline dyno reading and see whether the changes add or subtract from the result, not just the ultimate number, which isn't all that important in a roadbike, but all along the graph..
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