Cylinder sleeve removal?

[GearHD]

Hey All, I'm new here as well as the CB Honda platform.

I have 2 cylinder heads: 1 w/broken fins w/good cylinder sleeves & 1 w/good fins w/bad cylinder sleeves (need to be bored).

How do I remove the sleeves from these heads?

I already tried tapping(beating) them out & then tried pressing them out.
Sleeves won't budge & I don't want destroy them, so what's the trick?

I'm just wanting to build a stock motor to begin with, then I'll try an over sized next.

 

[dirtdigger]

Send them to Cycle X and have them do it. Its not really a do it yourself type of thing. They are press fit. Once pressed out the cylinder bores need to be checked for size and out of round then the new sleeves need to be checked for size to determine how much interference there will be when pressed in. After it is all done the top will need to be decked to make everything flat again. Cheaper option would be to find a block on ebay that has decent bores and have them measured and see which stock overbore you can use. If you try to press the sleeves out of the stock blocks without the proper support you will break them in half.

 

[GearHD]

Hmmm, that's not the answer I was looking for dirtdigger. I'm sure it's the right one though.

How about this;
I have the good head w/the sleeves that need to be over-sized & I have some 836 pistons, can Cycle X fit my 836 pistons & supply new rings for the over-sized bores?

If so, where are they & how do I get in touch with them?

Or, would it just be cheaper to take to a local machinist & have the work done?

Another issue: what else I'm I going to need to build an 836 engine - parts wise?

 

[dirtdigger]

Just to get the terminology right the cylinder block has the sleeves not the head. Yes they can do the bore. It depends on the brand and the age of the 836 pistons if they will have rings. If they are very old 836 pistons you may have to have some custom made. Some of the old school kits used specific rings, if they are newer Wiseco pistons then they should have rings.

http://cyclexchange.net/ Take a look through there web site, they really do offer more parts and have more experience than anyone out there with the old 750 other then maybe APE http://www.aperaceparts.com/. http://dynoman.net/ is also a good place to deal with. Kenny the owner of Cycle X really does know what he is doing as far as these motors. It is best to call them as they are short handed and dont always answer emails.

You can have a local machine shop do the work if they have done import motorcycle motors before if they haven't then stay away. Harley shops and automotive only shops have a tendency to make the clearances to loose.

As far as building a 836...it depends on what you are going to do with the bike. Street riding looking for more power then you can run stock rods but I would suggest having them shot peened and upgrade the bolts to later F2 bolts at a minimum. Better would be to get a set of Cycle X Super Rods, best is to get Carillo rods but they are expensive. Next on the list which is a must is heavy duty cylinder studs, stock ones will stretch and cause head gasket leaks. If you are taking the bottom end apart to rebuild and look over then replace the cam chain with heavy duty and new timing chain tensioner rollers. Also if apart get a set of new primary chains. If you want a snappy smooth motor have the crank lightened and balanced...makes a big difference. Take a look the tranny gears when it is apart and look for any rounded gear dogs...may want to replace with an undercut tranny if you are looking to add more power. In the head, more than likely you will need new guides and do a good valve job. Stock valves will work if you are sticking with small 836 motor. Porting is where all the power is in the 750 motor...expensive but worth every penny if you want some good power. You can run a stock camshaft with the 836 but you will be disappointed...you need to go a little bigger to help feed the displacement.

These motors do get expensive to build them right but if you half ass them together you wont be happy with the results. If you are looking for cheap then stay with stock bore. Next up is the 836 which is the cheapest of the bigger bore options. Next is 915 kits which are a little more involved but still basically bolt together without much trouble. Then you can get into the 970 and 1000cc and up and things get expensive because you have to run good rods and upgrade most of the internals as well and head and valve train. Take a look at my builds and gallery photos to get an idea of how much more involved they get.

 

[tommycarl]

Call Kate at Cycle One Manufacturing... they're in Oklahoma. I think they charge $50 a hole for the overbore and they'll get you everything you need. http://www.cycleonemanufacturing.com

My local automotive machine shop charges $60 a hole, so I may use them instead... but Cycle One has much more experience, so I'm still trying to decide which way to go.

 

[GearHD]

Thanks dirtdigger & tommycarl for your responses - very helpful.

I must have spent a couple hours on cycle x web site - amazing what they have done w/1970s technology.

Once I came back down I realized that I have limited funds available to build those type of bikes(super cool).

I have a lot of serviceable parts that I'm just going to have to make due with & several builds to do.

I currently have 3 complete (1973-1975) CB750s - 1ea 750 & 2ea 836. None of these have been ridden since the early 90s & scream "refurbish Me".

I'm probably dreaming, but the plan was/is to tear them apart, clean them up, replace whatever is needed, put them back together, & ride or sale what I don't need. So far I've got 2 of them in pieces & they appear to be in really good condition. No bent valves, warp heads/cylinder blocks &/or broken this or that internally. Mainly just cosmetics issues of old paint, broken fins, & rust.

I tried to post pics & couldn't for some reason? Any tricks to that?

 

[dirtdigger]

If you are lucky enough and you have new enough 836 wiseco pistons then Cycle X has them in stock normally. you will have to do a little looking to see if you can determine what the pistons are. I have a set on the shelf I can measure the ring grooves once you get yours measured.

 

[GearHD]

OK dirtdigger, this is what I have;

Piston OD: 2.535"
Top grove: .060" or 1.529mm
Mid grove: .059" or 1.478mm
Oil Ring: .099 or 2.52mm

The actual rings themselves:
Top & Mid: .058"
Oil ring: .195"

I got these measurements with a feeler gunge & a micrometer. The measurements are of the Hi-compression piston. Apparently I'm missing one of the other set.