Cam lift specs for 750SF2?

[arancia]

I'm having a machinist/engine builder measure it again later today.

While I imagine it'll be clear to him based on the position of the lobes, please ensure that the engine builder understands the cam, rocker, valve layout of this engine and does not think it's a direct cam to bucket to valve setup like the triples - take the whole set of bits including the rocker arm along for his inspection.

 

[TeddyG]

Thank you again- I'm hoping this machinist/engine builder who comes recommended from a friend who owns a Norton and Ducati that was serviced by him, knows what he's doing. He did however, say that multiplying the 1.29 ratio refers to valve lift. According to the spec sheet, my 74 SF2 has a 7/1 cam, but I can barely see stamping on the end of the cam (with the 8mm threading) that may or may not say "7". However, since I'm seeing 33.55mm on my lobes, it's very close to your numbers, so I'm assuming the cam lifts on mine are OK.

 

[piranha-bro2]

Ted, there's no mention anywhere in spec tables of measured height of lobe - only LIFT figures (which means the 1.29 or 1.3 ratio must be applied). Yours look very much like std SF2 and are in perfectly good condition. I think you could save your dollars and put them to use elsewhere.

 

[TeddyG]

Yes and thank you Piranha- I have been referring to the LIFT figures of 10.09/IN and 9.72/EX, and was just pointing out that my lobe measurements of 33.55 were close to Arancia's, which indicates that mine are probably OK. I was initially calculating the lift numbers w/o including the 1.29 ratio for the followers, since I didn't see that mentioned in the spec sheet. And yes, the machinist has recommended a valve job and rebore/new pistons, so hopefully that will finally resolve the motor's lack of power.