Topic: My K8 re-conditioning

[grcamna2]

Left my cylinders/new pistons at a different machine shop today.  Talked with the guy that said "I do all the cylinder boring here, and have done a lot of motorcycle cylinders".

I gave him the target spec for clearance after honing is .0008", he said "sounds tight, but will do if that is what you want".

Hopefully will turn out ok, will find out I guess.

I think that's an encouraging response from the machine shop.
I used to live in Toccoa,Ga. I found a good machine shop in Athens,Ga. where I was seeing an Audiologist Dr. for my hearing.I brought a small single cylinder w/ new OEM Honda piston into the machine shop and specified a factory Honda clearance of "about .001" piston to cyl. clearance,no more" to the machine shop to which they said the same exact thing to me 
They did the job and it turned-out great;I had plenty of compression and did a proper break-in and that little 2-stroke 50cc bike ran great with plenty of compression and power for a long time. I rode it from Toccoa,Ga. to Athens,Ga. a few times a week back and forth for a while as long as I lived in Ga. I was also getting my allergy shots down there,etc. Athens,Ga. is where Partzilla is, so getting Honda parts from them.
I rode that little bike at 25 mph(close to top speed & I'm 225lbs)the entire journey;a 1977 Honda Express 
They did the engine machine work 'to my spec'    !
I was very pleased with the shop following my specified instructions. 

[denward17]

Got my cylinders back from the machine shop and the best I can tell using the measurement devices that I have, it appears he came very close to the number I asked for.

I'm using this to get inside measurements:

https://www.amazon.com/dp/B08MQCTTM3?psc=1&ref=ppx_pop_dt_b_product_details

Not the most accurate but probably close enough.
All the new pistons are snug while sliding through the cylinders.

[PeWe]

Do not forget to check ring end gaps.
They can be too tight in need of filing.
My CI rings needed some.

[denward17]

Checked all rings today in each cylinder and aligned each set to a hole.

Had to file all 4 top rings to get .008" end gap.

Hopefully next week I can start putting it back together.

Pic of cylinder after paint.

[Stev-o]

Looks good!

[BenelliSEI]

Nice work, we’re pretty much at the same stage!

[PeWe]

Look like new

[denward17]

I used sandpaper of different grits on a board to grind off each end of the dowel pins in pic so they would sit flush on cylinder.

My cylinder was milled ~ .003", so I ended up taking about the same off of each pin.

Trying to get everything in order to start putting it back together next week.

[grcamna2]

Make sure to get every last bit of grit out of each one of those cylinders;the hone leaves very fine stone-grit in the cross-hatch marks and it takes plenty of washing to get all that out.

I have used non-abrasive GoJo hand cleaner and completely(sometimes more than once)rubbed all the surfaces of each cylinder grit-free. I would apply something like WD40 after each cleaning so the cylinder wouldn't 'flash rust' after each rinse.

[denward17]

Make sure to get every last bit of grit out of each one of those cylinders;the hone leaves very fine stone-grit in the cross-hatch marks and it takes plenty of washing to get all that out.

I have used non-abrasive GoJo hand cleaner and completely(sometimes more than once)rubbed all the surfaces of each cylinder grit-free. I would apply something like WD40 after each cleaning so the cylinder wouldn't 'flash rust' after each rinse.

Thanks for the reminder, I did wash it in a utility sink with a mixture of Dawn soap/simple green aircraft cleaner.  I then hit each cylinder with acetone until the paper towels did not stain.  Plan to wipe it several more times before assembly.

[grcamna2]

Make sure to get every last bit of grit out of each one of those cylinders;the hone leaves very fine stone-grit in the cross-hatch marks and it takes plenty of washing to get all that out.

I have used non-abrasive GoJo hand cleaner and completely(sometimes more than once)rubbed all the surfaces of each cylinder grit-free. I would apply something like WD40 after each cleaning so the cylinder wouldn't 'flash rust' after each rinse.

Thanks for the reminder, I did wash it in a utility sink with a mixture of Dawn soap/simple green aircraft cleaner.  I then hit each cylinder with acetone until the paper towels did not stain.  Plan to wipe it several more times before assembly.

  very good. I've made the mistake of not getting them clean before;it wore the pistons/rings prematurely.
Be sure to blow-out each cylinder with compressed air when it's complete to remove the lint from the paper towels.

[HondaMan]

I've "trained" my machine shop to post-wash the cylinders after boring in their parts-washer machine, then spray each bore with a protectant. That way, I don't have to do it, nor worry if other parts are taking too long and holding up the reassembly. Now they don't even charge me extra for it, and have started doing it to all the smaller blocks they bore (mostly car engines).

But then, I'm bringing something to them very frequently, lately, which makes for a good relationship!

[denward17]

Starting process of putting the engine back together.  Waiting on a couple of o-rings between the head and cylinder.

New pistons with rings installed on connecting rods, used assembly lube on wrist pins. 

Rings installed with letters up, silver ring in top groove.  No lettering on oil scrapper rings.

Do you guys put the rings in the bore dry?

[PeWe]

I use oil or a little assembly lube so it will glide on. Especially at the bore bottom where rings need to go in first.

When all are in, I rotate crank carefully and look at the oil film on bores for scratches rings might do if having sharp edges.

When all are good wipe off some lube in bores.

[denward17]

Installed cylinders over the pistons, left just off the seat so I can use some permatex on the base gasket.

Hopefully will receive the o-rings (between the head and cylinder) by the weekend so I can button up the cylinders/head.

[BenelliSEI]

Looks great!

[PeWe]

You do not need permatex on base gasket.
It will make next cylinder lift to a pain.

[grcamna2]

You do not need permatex on base gasket.
It will make next cylinder lift to a pain.

I use Permatex Copper Spray-A-Gasket;let it set-up and dry first.

[denward17]

You do not need permatex on base gasket.
It will make next cylinder lift to a pain.

Thanks, I was going to put a thin coat just were the oil returns are.  Is that a bad idea?

Think I read Hondaman does that.

[BenelliSEI]

You do not need permatex on base gasket.
It will make next cylinder lift to a pain.

I use Permatex Copper Spray-A-Gasket;let it set-up and dry first.

I do too. The one I have is a red spray that goes on very thin (Felpro?). It completely dries and I usually tie the gasket to the underside of the cylinders with a few thin rubber bands. Cut them off and drop it when the head is ready to go on.

Another thing I like to do (probably a waste of time) is torque down the head, leave it a few days, and then do it again (before installing the cam towers).

[grcamna2]

You do not need permatex on base gasket.
It will make next cylinder lift to a pain.

I use Permatex Copper Spray-A-Gasket;let it set-up and dry first.

I do too. The one I have is a red spray that goes on very thin (Felpro?). It completely dries and I usually tie the gasket to the underside of the cylinders with a few thin rubber bands. Cut them off and drop it when the head is ready to go on.

Another thing I like to do (probably a waste of time) is torque down the head, leave it a few days, and then do it again (before installing the cam towers).

The red spray you use,what brand? is it called High Tack ?

[BenelliSEI]

You do not need permatex on base gasket.
It will make next cylinder lift to a pain.

I use Permatex Copper Spray-A-Gasket;let it set-up and dry first.

I do too. The one I have is a red spray that goes on very thin (Felpro?). It completely dries and I usually tie the gasket to the underside of the cylinders with a few thin rubber bands. Cut them off and drop it when the head is ready to go on.

Another thing I like to do (probably a waste of time) is torque down the head, leave it a few days, and then do it again (before installing the cam towers).

The red spray you use,what brand? is it called High Tack ?

That sounds right. I’ll find a can tomorrow and let you know.

[BenelliSEI]

Here is the spray I use, The can is at least 15 yeas old! 

[newday777]

Here is the spray I use, The can is at least 15 yeas old!

I remember having some of that, might have some still.....

[grcamna2]

Here is the spray I use, The can is at least 15 yeas old!

Yes,the Permatex company has had that spray for quite a while;it works well on valve cover gaskets,etc.