Brad The Bike Boy: Ducati 900: W heads vs V heads

Tuesday, November 13, 2012

Ducati 900: W heads vs V heads

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I had a fellow named Wilco send me some dyno runs for his Cagiva Gran Canyon (fuel injected 900 motor) before and after a cylinder head replacement. Originally fitted with the same style heads as the later 90's M900 (W stamp) fitted with the 750 sized valves and 750 OR/VR cams, he had replaced them with some V stamp heads from a carburettor model 900SS running the OHT/VHT cams. The OHT/VHT grind is little smaller than the 900SSie cams that I fitted to a Gran Canyon with std heads some years ago. See http://www.bikeboy.org/grancanyon.html for more info.

As you can see, the bigger valves really help wake it up. It's the result I was hoping to see with the cams alone. Obviously the valves are more important. For a carby model M900 with the long manifolds the top end increase might not be so great, but even if it peaked at 7,000 rpm it is still a large increase.

Thanks to Wilco for supplying the info.

There's some more info in this youtube clip:

https://www.youtube.com/watch?v=Ec2CM4DnyDM&feature=g-upl

2 comments:

Unknown said...: Where did that article about the engine numbers re V and W heads on the M900 go?; May 5, 2021 at 2:53 AM
Wilco.cwx said...: https://www.bikeboy.org/grancanyon.html

greetz wilco.cwx; August 22, 2021 at 1:08 AM

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