Piston ring compression tool

[Stralya]

Hello yet again,

Well today should have been the day pete and I finally installed my Wiseco big bore kit.

Pete came over bright and early on his highly polished '81 Special, I had the motor torn down ready for the new pistons to be fitted.

They went on easily then.......

Anyone know of a good substitute for a piston ring compression tool? We were using oversized hose clamps but could only get two pistons fitted into the block, there wasn't enough room to fit the other two between the bottom of the block, the top of the hose clamps and the top of the engine case.

I still haven't located the missing three litres of oil either.

What a waste of a day, it was beautiful too! Mid 20's, no wind and a cloudless sky

[TopCatGr58]

Hey Stralya,

I thought you Aussie's were big tough guys? You don't need no stinkin' ring compressors!!!!

When I did mine, the jugs had a nice taper at the bottom. I just put the jugs on, had the pistons/crank positioned so that the outer 2 were up, and slightly tilted the jugs to fit one in at a time, used my bare hands to squeeze the rings with copious amounts of oil in the jugs, rings, and worked the jugs down onto them, then slowly rotated the engine enough to bring the center pistons up and repeated the process, got them in just fine with "maybe" a little pinching of my fingernails, but that was it!
T.C.

[79XS11F]

When I did mine I failed to ask the machine shop to chamfer the bottoms of the bores and it was a NIGHTMARE to get it together alone. I did however manage to get the rings in with hose clamps. I set all 4 pistons at middle position for my effort. The problem I had was that the hose clamps would not stay put and the top ring would pop out. It took several tries to get every thing in. I did not make any of the piston support blocks shown in the manual but would if I were doing this sort of thing again. I would also have the machine shop put a NICE chamfer at the bottom of the bores.Rob

[petejw]

Hey TC
Us aussies are big tough guys,
with weak little fingers. lmao :-)

This is the second rebuild of this
motor in as many weeks,
the first block we used had the taper on the bottom,
the pistons slid in very nicely, unfortunately the parts
were crap and now the second time, using another
block which had been bored out for the new stuff
doesnt have the taper on it.
We tried using hose clamps, this didnt work.
So now, stralya's taking the block back 2 c if they
can put the taper on the bottom of it.

[Stralya]

I took the cylinders to the machinist this morning. No problem he said, I was almost going to suggest you get that done when you brought them in for the re-bore he said.

Thanks I said.

Watch this space.

[Shappers]

A trick I use is to cut up old beer cans (or Fosters tinnies in your case). Oil it up, wrap it around the piston and secure with cable ties (zip ties).

The best part is making the cans empty first

[Stralya]

No Fosters cans here

Thanks Shappers.

I don't drink Fosters but luckily, the boxes and boxes of empty Tooheys New cans I have lying about here in Blotto Grotto are exactly the same size

I'll keep that trick in mind.

Finland eh?

Who owns the Pub there now?

Dan.

[Shappers]

Well...

My favourite is Lapin Kulta made from the wild sparkling waters of Lapland.

But I like to drink Fosters when I'm thirsty

I'm going to have to search out some Tooheys...

[Stralya]

Three weeks later....

Yipee!!!!

My big bore kit is now installed. Here's what myself and Pete learned.

Always have two people do the job. One person, no matter how lithe and nimble, just can't get from one side of the bike to the other quickly enough. (I can hear Pete laughing at lithe and nimble, I'm an immense fat freak!)

Do pistons 2 and 3 first. Turn the crank until they are uppermost on the stroke. If you use hose clamps like we did snug them up fairly tightly, just enough so that you can still move them but with a fair bit of effort. Snug isn't firm enough.

If you don't have the tool that stops the pistons dropping down, a narrow piece of clean wedge shaped wood will do the job, place the pointy end under either of 2 or 3.

When you have all the rings compressed, mate the very top of the pistons into/with the the block. Make sure the bottom edges of each cylinder sleeve is beveled.

Once you have that done, stand up on either side of the bike (which needs to be on the centre stand) and count 3..2..1, then gently apply downward pressure on the block. The sleeves should push the hose clamps down and the piston and rings slide into the piston like the proverbial finger in a dyke.

Don't try tapping the block down onto the pistons. All that does is shake the bottom or top ring free of the hose clamp and all you'll do is bend or break a ring or two. (I said bad words and threw stuff)

Remove the wood wedge and slide it under 1 or 4 and remove the hose clamps from 2 and 3. Rotate the crank just enough to make space for the wedge.

Clamp 1 and 4, do the stand up on each side and the 3..2..1 thing and gently apply downward pressure to the block and bingo!, job's done.

On Friday I'll be finishing the assembly, carbs, exhaust etc and starting it up.

Oh, make sure you smear new oil (dosen't matter what weight) inside the cylinders and make sure the rings move in their grooves freely and the ring gaps are 180 degrees from each other.

I know most of the experienced members know all this already, I just thought I'd share with those who might struggle with the project like I did. Pete only struggled with his assistant.


Dan.