DaveM. Are you here.

G'Day Dave, or anyone that knows the answer.
I am seeking your opinion on the 4s Cam that you fitted to your 71.
I have a Combat under reconstruction, and have the chance to aquire a 4s cheap.
Did you raise the compression and fit bigger carbs, or just fit the Cam.?
Thanks..AC.

I think fitting a 4s cam is only a good thing when you are racing and then you obviously will fitt higher compression etc
On the road a 4s is useless , indeed a bad idea because it will only breathe higher up the rpm scale (as in racing ) and I do suspect that you are not reving a roadbike higher than 5000rpm on normal use . It will only be slower and lumpier .
Forget these fairytales about fittng a cam and have THE Commando
But it is a good cam if you are building a blueprinted Norton


oops I just saw there are 2 threads on this Sorry

Hello Aussie Combat, I have fitted 4S cams in a number of bikes and I like the power characteristics, I fit them to any project where I need a new cam or a re-grind. I understand that they are supposed to have a similar top end performance as a 2S but with a better mid range. Most of my riding is for fun and pleasure and while I like to take it up to nearly 7,000 RPM occasionally, I normally ride it in a sensible fashion and find it is perfectly useable from slower speeds on up to and over the legal limit, this is definitely not some clutch slipping, narrow powerband nightmare, although I think you would find it wouldn't add much to a standard bike without the 32 mm ports and a higher compression ratio.

Regards

Dave M

Thank you Dave, and Jim C,
No offence lynx.
I have been told similar things by others and am willing to have a go.
Nothing ventured nothing gained.
AC.