Topic: '77 CB750K Engine Rebuild

[Empire57]

Hey Guys,

This is my first bike project... I've worked on cars, trucks, tractors and ATV's but never tackles a bike motor. My question is this.. If I'm going to do a full rebuilt and upgrade (which is needed), I want to do this right... Could someone please provide some guidance as far as good quality parts and specs for rebuilding this 77 CB750K.

The current set up is completely stock and if possible I would love to keep the kick start.

Also, my biggest question is regarding comparability.. If I throw in a 836cc big bore kit, what size of carbs are ideal or can I use existing 28's, and if I bore the block what changes do I need to make to the top end, bigger cam sizing etc.

Thanks guys,

Empire57

Budget for the motor: 2K

[wrenchmuch]

If you go 836 the stock carbs will work well. I have a wiseco 836 with a webcam #41 and run stock carbs (k1). There are cheaper pistons available with less compression then the Wisecos or JE pistons. You can find these on eBay. Have a look at the inside of your engine and see what condition it's in. Primary chain and cam chain tensioners
and guides are probably hard and in need of replacement by now. After you assess  the condition of the parts you have you can see how much of your budget is left.

[Dyrden]

Yup.  Pull the head and jugs and see whats up before you go ordering parts.  Ive got mine apart, 836 kit going in.  New valves, guides and seats being cut.  Also putting in HD studs.

[Empire57]

Thanks guys for the info and guidance.. Once I get the motor pulled and torn down I'll take a look and see where I stand. Thanks again!

[wrenchmuch]

I'm just up the road from you if I can help .