Hopefully not a big, boring thread...

[Bagger John]

But a thread about big-bore kits and other modifications for them to work optimally.

Several decades ago I did a Wiseco 836 kit conversion to one of mine. I seem to recall the kit included heavy-duty studs (or maybe not...) but the shop I bought the parts from made sure they were included. This outfit also did the boring work. I ran a 4-1 header and individual K&N air cleaners. No other head work or carb work other than jetting was done.

For the life of me, I can't remember which octane fuel I used...

Fast forward to the present. I want to build another solo tourer/commuter using a K7 or K8 as a base. This setup will have a Windjammer and set of Shoei SB-2s; a short sissybar/tail rack and engine guards. So a bit of extra power would be nice. An 836cc conversion is perfect; exhaust will be MAC 4-2 if I can find the right set. Also planning on using the stock air box.

Questions arise: Are the stock con rods and bolts enough for this application, or should I look to an upgrade? How about cams and cylinder head work - not looking for a race engine but to broaden HP/TQ where possible; especially the latter. Carb swap - go with the setup off a 72-76, a different arrangement (larger throats) entirely?

I ran a Barnett clutch in the original conversion and used a Lockhart oil cooler - good to have either/both?

Input welcome. I can yank the top end and send the cylinder block, head and any required parts to whomever for boring/porting and valve train work as needed, so I'm open for suggestions/guidance here.

 

[dirtdigger]

836 can use stock rods. I used to have them shot peened then upgrade to f2 bolts. Now days I dont mess with that and throw the cycle x super rods in there....never break them in a 836 end of story. Depends on if you want piece of mind and no worries. Have crank balanced but not lighteded for a touring motor. With 836 get the 10 to 1 compression then use premium should be good to go. Always use heavy duty studs even for stock rebuilds. Always use heavy duty cam chain and at least new primary chains...upgrade if you can afford. New cam and primary chain tensioners a must...use oem and will be fine. Have cylinder top and head surfaced for MLS gaskets and will have no leaks in the future.

At a bare minimum have the head rebuilt. I use Cycle X most of the time for all machine work but APE is good as well. I like the cycle x valve guides better though. You can stick with stock valve sizes but mild porting will help considerably. A cycle x khd cx1 cam would be a good fit. Not big but should help bump power. With new cam use new rocker arms and should use new springs.

Stock clutch should work if use new fiber plates but cycle x has options depending on how much you want to spend

Stock carbs are fine especially if you want to keep the stock air box but will obviously need jetting, key hole carbs are harder to jet then the old round tops but totally do able.

Building the 750 is kind of a rabbit hole, lots of neat parts available but its very easy to spend a lot of money because a lot of things should be upgraded when you have it apart.

These are just some of my suggestions. Take a look at the cycle x site and you can see how much is available for the cb750 motor.