TOPIC:

Anyone have experience with Flex Hone?

www.brushresearch.com/pdf/GB.pdf

Both the ball/bottle/brush/flex/dingleberry hones (whatever they call it in your area) I bought from amazon.com for my 550 and 750 are that exact BRM brand. They come in different grit sizes and both have proved to be indestructible.

Just general information for any one wanting to try this....
Get a rubbermaid storage tub or cardboard box to put your cylinder block down into, because even at slow honing speeds you will fling lubricating oil all over yourself and the garage. Because you are using some kind of lubricating oil aren't you.....of course you are.

loudhvx wrote: Anyone have experience with Flex Hone?

www.brushresearch.com/pdf/GB.pdf

This is the exact type of hone we used. Granted, as Daftrusty said, we didn't spend a lot of time trying to get it crossed hatched, we basically just went up and down a few times and tried to see if it'd knock the corrosion off enough to see if it'd work...obviously without a lot of luck.

Daftrusty wrote: The cylinders Steve posted will work perfectly, but they are cosmetically different than the gpz cylinder block. The fins are rounded and not squared angles like the gpz cylinder head. Not a big deal, but if selling in the future, its a dead give away that something went wrong.

You can't buy sleeves from Kawasaki, but you can take the sleeves out of another 550 block and put it in yours. All you have to do is stick the cylinder block in the oven @ 450 degrees and bake it for 45 min. The sleeves will literally fall out at that point. But I don't advise trying it ( I have tried it multiple times) and when heating the good block and inserting the "new" sleeve, upon cooling the sleeves will get squeezed out of the block from cooling aluminum leaving the sleeves improperly seated in the cylinder block. This option is best left to a pro and it will cost more than a used engine would.

I would remove the scuffed piston from the engine, remove the rings, clean it up and try to gently smooth down the scuffs with fine sandpaper or a scotch bright pad. I don't think the scuffs are terminal and the piston will still be usable. Try it at least before dropping $$ on a NOS one and using it in the corroded bore.

You need to google "cylinder hone cross hatch" and research it some.
You have indeed honed the cylinders, but not in a way you can ever run pistons in them again. It has to have a 45ish degree crosshatch pattern and not concentric circles. The proper honing is for future lubrication of the cylinder. Done incorrectly, your pistons and rings will eat themselves in short order.

These are exactly the same questions and answers I had to research when I was trying to make a usable cylinder block and matching pistons.
I ended up finding a used cylinder block on ebay, honing it and using new rings.
But your results may vary.

Roger. Ok, well, I really don't want to go to KZ cylinders since they are rounded - I hadn't noticed that until you mentioned it. Good eye!

So now I'm torn on whether I should buy a Flex-Hone and try to do it myself or just send it to my machine shop guy. He's real good - I could let him know what I'm looking to do with it I suppose.

So Rusty; you think this Flex Hone is a pretty easy/good way to do it? I've actually wanted to buy one before, but always doubt myself figuring I'd just booger up my bore. What grit would you go with for this kind of project? I'm guessing I'll want the size that's closest to 58mm...

By the way guys, I want to thank y'all again - I really do appreciate all your input, thanks for sticking with me on this project!

S/F,

-Matt

Welp, I did some reading and watched some videos and decided to take the plunge, I think I can do this. I bought a 2.5'' Flex-Hone in 180 grit and some cutting fluid.

Will be here Thursday, looking forward to this now actually!

You are on your way to mastering another useful skill! That's what I did, I watched videos and read everything I could find. Got a hone, some oil and went to work making a incredible mess in my garage on a junk cylinder block. (Seriously, set the cylinder on some wood blocks in a high sided tub so you don't fling oil everywhere. There are still oil stains on my garage wall.)

You beat me to replying to your question.
The 60mm (2 3/8") hone is the correct size for the 550 cylinders. The hones are actually bigger than the size listed. So a 2.5" will be about 2.75" in diameter. So I might be a tight fit shoving it in the 58mm bore but it "should" work.

Have fun and post your results.

Ball hones are only to be used to remove glaze and very light surface rust. You should not attempt to use them to remove rust pitting and/or deep bore scuffing.

For chrome rings like Kawasaki uses the proper hone grit to use is 320. 240 is safe as well, just use less passes. 180 is too rough I think.

I've tried to swap cylinder liners before and it's easily doable. You can heat the cylinder in your oven or BBQ and the liners will fall right out. When you swap in a different liner it's very likely to experience a level difference on the deck surface. I'm pretty sure that Kawasaki decked the block after the liners were installed.

There is an outfit in England that sells OS pistons/rings for the 550 for a reasonable price. Cruise Image sells a big bore kit for dirt cheap too. I'd make the jump up to one of these options and forgo the risk taking.

Nessism you are correct. He won't be able to repair the corrosion in the barrel, but he might be able to remove most of the staining from the barrel to assess if it is worth running. The worst spot is in the area where the piston stroke will not reach.
For $20 he can possibly "save" the cylinder block and bolt it back together if his budget is really tight.
I had a machinist do this for me and said "I honed all the cylinders, but I can't get the corrosion out of the one and I honed it until it's out of specs and useless. That will be $100 please!"
All his other options will be very expensive. Just trying to keep him from making expensive mistakes that I made.

I still have a resleeved block that I did in the basement. I could get the sleeves flush until it cooled and it squeezed all the liners out a couple of thousands. So there will be an air gap even if I had the head decked which would lead to the sleeves coming loose once run. I needed to try tourquing the still hot cylinder block down in a engine or fixture to prevent it from getting distorted and squeezing the liners out. Maybe one day I will try. Maybe not. I already have to many projects.

Food for thought.

In 87 I put in the 750 sleeves from the Z2 barrels. With a little heat I was able to drive them out using a block and a hammer. I had Clupper racing bore them out to 1015. They complained they kept spinning but got them done. Lots of material to take out. The sleeves were rusty inside and I thought the boring would get past the staining. NOPE There was still dark patches even with all that material gone. I ran them until 13 when I got 1015 barrels due to a oil problem.The cast iron sleeves are very porous. Didn't come apart though. I still think getting some used sleeves and pistons are your best bet.
Steve

Daftrusty wrote: You are on your way to mastering another useful skill! That's what I did, I watched videos and read everything I could find. Got a hone, some oil and went to work making a incredible mess in my garage on a junk cylinder block. (Seriously, set the cylinder on some wood blocks in a high sided tub so you don't fling oil everywhere. There are still oil stains on my garage wall.)

You beat me to replying to your question.
The 60mm (2 3/8") hone is the correct size for the 550 cylinders. The hones are actually bigger than the size listed. So a 2.5" will be about 2.75" in diameter. So I might be a tight fit shoving it in the 58mm bore but it "should" work.

Have fun and post your results.

Glad I checked my email! I was able to cancel the order before it shipped and get the right one!

Also, to Nessism's point below, I ordered a 320 grit as well! I figured I can do more reading between now and Thursday and either return one of them or just hit the cylinders with the 180 first for about 15 seconds and then the 320 for 30 or so seconds...can't imagine two grits could hurt...

Nessism wrote: Ball hones are only to be used to remove glaze and very light surface rust. You should not attempt to use them to remove rust pitting and/or deep bore scuffing.

For chrome rings like Kawasaki uses the proper hone grit to use is 320. 240 is safe as well, just use less passes. 180 is too rough I think.

I've tried to swap cylinder liners before and it's easily doable. You can heat the cylinder in your oven or BBQ and the liners will fall right out. When you swap in a different liner it's very likely to experience a level difference on the deck surface. I'm pretty sure that Kawasaki decked the block after the liners were installed.

There is an outfit in England that sells OS pistons/rings for the 550 for a reasonable price. Cruise Image sells a big bore kit for dirt cheap too. I'd make the jump up to one of these options and forgo the risk taking.

kzrider.com/forum/2-engine/372962-sleeve-installation

kzrider.com/forum/2-engine/392582-cylinder-sleeves-replacement

www.kzzone.com/blocks.html

www.mtceng.com/mtcproducts/products/cylinder-sleeves

Good Fortune!

The liners are a relatively light press fit in the block. After installing the liners in the block I was working on a couple of them popped up a little but it was easy to press them back down using a cheap hydraulic press. I even reset one of them with a 2x4 and a big hammer.

Interestingly, Suzuki GS bikes color code the liners and blocks so they could control the press fit.

All this said, I wouln't attempt to swap around liners that way unless you were planning to bore them afterwards. The press fit will affect the roundness and it's always best to start fresh.

On my 750 with only 11k miles I was surprised to see just short of .001" out of round and taper in the bores. The piston to cylinder clearance was large too - almost .004". I concluded that Kawasaki did a crap job of boring my block. I bottle brush honed the holes with a 320 hone and threw in new OEM rings and the engine is running great regardless. If I had to do it again though I'd be tempted to get those OS pistons from England and tighten things up.

The PDF says they have a specially formulated oil for the Flex Hone. You may want to order that too, if it's not too late. They say to wash it out with hot water and soap/detergent, and not to use solvents at all. Also, on the PDF they address the fine/coarse grit issue. Seems like If you are going to use synthetic oil, you will want the fine grit. Coarse grit might lead to higher oil consumption.