Topic: Cam questions

[sjdigiov]

Hi,

I'm currently rebuilding a completely trashed '74 Cb750. The top end from the bike is completely unusable. I luckily found someone selling a ported head in good condition for cheap. The PO said it was made for an Andrews "A" grind cam. They are no longer in the Honda market so I'm wondering if anyone has any advice on how to either find one for sale, or if there is another company that manufactures a similar and usable cam.

Also the Carbs that came with the bike are mostly powder on the inside, I genuinely had no idea that aluminum could corrode so much. So if anyone also has tips on securing a bank of carbs that would be appreciated. I'm doing this on a college student/bartenders salary so cheaper would be better. 

[samm_j2]

I am sure some of the cam gurus will pop in here to make some suggestions. I have some old carbs off my 78cb750f I
do not need. I can let them go for a reasonable price. Happy to help another college student out. They are the keyhole type carbs, some people like them and some aren't very fond. I like how that have an accelerator pump. To each their own. If you are interested shoot me a message. Happy studying!!

[bryanj]

You need several extra bits to fit pd carbs. There should be lots of carbs from 70 to 76 out there

[PeWe]

Pistons with higher compression  might be needed depending on how the head is ported.
If chambers are opened as was common back in the days for pistons with wider and higher crowns. Stock pistons will then create very low compression.
It is low enough as stock, around 150PSI when good, larger chambers will reduce that.
The fun starts from 170PSI. Max around 200PSI on tap fuel like Shell V-Power as I have seen.

Cam might not have that high lift so deeper valve pockets in pistons is needed.
Included in higher compression pistons.

[Bodi]

Carb bodies are not pure aluminum but yes, aluminum corrodes. Corrosive residue from evaporated gaslline is not kind to the carb alloy but a carb simply drained before storage won't corrode much at all. Bodies with terrible looking corrosion will often still be usable, a bit of pitting that doesn't destroy anything won't be fatal.
Head porting for a specific cam grind does not make sense to me. Porting aims to improve gas flow in and out of the cylinder. Why would if matter what cam is used?
Cam grinds range from stock to extreme race profiles, with a detour for forced induction. There is no magic super cam grind, for any gain you also lose something. Race grinds that give impressive horsepower at high rpm are generally unusable for street riding.
I think looking for a cam that suits your riding is a better idea than searching for an Andrews A because the head was "ported for it".

[ekpent]

 A good condition cheap stock cam would probably get you on the road in fine shape.