Angled carb stubs for 750s?

Hi Ernesto - Tis a problem getting long  bellmouths on an SF with PHF carbs. I don't like increasing inlet tract/ valve angle - I have gone the other way and angled my carbs up by 10? - I had to shorten my carb extensions and also have to angle my carbs inwards to clear the fuel tank. This will become a bigger problem when I do the same on my 860cc with 40mm PHM's - but I have a cunning plan to help me out with this one!! -  I know the long bellmouths look good but they don't really do anything that shorter ones wouldn't - Regards - Phil
 
made some 10 degree angled manifolds from billet alloy to suit 40mm Mikuni's for one of the Twisted Twins but in the end made another straight set which is what we wound up using in the end
with the 750 manifolds you could mount them with the angle facing up or down

the spare set of angled manifolds that I have left as mentioned above will not suit a standard head as they were custom made to match the port shape on an extensively ported Phil Todd head, we had to custom make the o-ring groove and it would not have been possible to achieve the groove shape without a CNC machine

I'm with Phil on this one, limited value going to longer stacks, better gains to be made chasing the manifold length and changing to a better bell mouth shape on the velocity stack, look at the recent changes in shape to stacks as used on drag racing machines with the inverted lip shape, huge gains in air flow made

 
I've put these shots up before, but they show the problem with frame clearance and also how much more of the inlet valve is exposed to the incoming charge by closing up (downdraught) the angle between port and valve. This 750 does perform extremely well - Regards - Phil
 

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