Topic: Bore / hone thoughts

[Tom R]

Cb750 .75 over bore / hone just back from the shop. This doesn’t seem to be as nice of a finish as cylinders I’ve had done before. Seem Acceptable? I haven’t scrubbed them yet, but that won’t change crosshatching or finish. 

[bryanj]

Seen better and ocasionally worse but more important is what piston clearance they gave it

[willbird]

Total Seal piston rings have some good videos explaining what the surface finish should be like and how they actually measure it. There are tools designed to measure it, even the folks with the older manual equipment can still achieve a quantifiable result if they use the measuring tools. The best stuff is the Rottler type cnc machines and diamond stones. The Plateau finish which is put on after the cross hatch might only be 6 strokes or so to get the desired flat tops on the mountains and valleys :-). 

https://www.youtube.com/@TotalSeal

[Tom R]

The clearances are ok.  .0009 - .0011. According to my micrometer and bore gauge.
I’m using Honda rings.. which I believe have a chrome top ring.

[Stev-o]

I dont see an issue from here....

[Tracksnblades1]

What is your taper..?

[timtune]

I'd say the cross hatch angle is off, but I'd have no problem using them.

[Tom R]

Thanks for the replies. I’ve sent 6 or 7 cylinders and blocks out in the past that didn’t come back looking so inconsistent and sloppy. I’m sure it’ll run, and it’s a stock rebuild… I’m trying to decide if I’d use this guy again or not. He was $100 cheaper.

[Tom R]

What is your taper..?

No taper. He did do a good job of keeping them straight.
As tempted as I am to “fix”  the crosshatch with a ball hone, I think the best thing is to just scrub them up, and put it back together so I don’t have to look at it anymore.

[willbird]

What is your taper..?

No taper. He did do a good job of keeping them straight.
As tempted as I am to “fix”  the crosshatch with a ball hone, I think the best thing is to just scrub them up, and put it back together so I don’t have to look at it anymore.

I suppose you could ask if they are achieving a defined hatch plus plateau, I would hope so. From my limited learning both the mountians and the flat tops are key components of a working finish. 

[Tracksnblades1]

What is your taper..?

No taper. He did do a good job of keeping them straight.
As tempted as I am to “fix”  the crosshatch with a ball hone, I think the best thing is to just scrub them up, and put it back together so I don’t have to look at it anymore.

Do you know what grit stones were used for your chrome rings final finish..?
You can use a magnifying glass to see if it’s been plateaued hone as mentioned by Will…
It will look similar to a tiny pyramid with the top filed flat..millennium technology provides plateau honing..

[MauiK3]

Be sure to post some updates when it's running. Looks ok to me but I'm a real amateur.

[fire113]

http://forums.sohc4.net/index.php/topic,68869.msg761276.html#msg761276

14 Years ago I did my K1 engine, but I went to 836ccm with wisecos pistons and rings but You can see the crosshatch at the pictures.

Today I ordered a new wiseco head gasket because after 14 Yeas and hard driven kilmeters I found 5 oil drops under my K1 

 

[Tom R]

What is your taper..?

No taper. He did do a good job of keeping them straight.
As tempted as I am to “fix”  the crosshatch with a ball hone, I think the best thing is to just scrub them up, and put it back together so I don’t have to look at it anymore.

Do you know what grit stones were used for your chrome rings final finish..?
You can use a magnifying glass to see if it’s been plateaued hone as mentioned by Will…
It will look similar to a tiny pyramid with the top filed flat..millennium technology provides plateau honing..

He said 220 to 280 to a brush to finish it off.

[Tracksnblades1]

What is your taper..?

No taper. He did do a good job of keeping them straight.
As tempted as I am to “fix”  the crosshatch with a ball hone, I think the best thing is to just scrub them up, and put it back together so I don’t have to look at it anymore.

Do you know what grit stones were used for your chrome rings final finish..?
You can use a magnifying glass to see if it’s been plateaued hone as mentioned by Will…
It will look similar to a tiny pyramid with the top filed flat..millennium technology provides plateau honing..

He said 220 to 280 to a brush to finish it off.

280 is a more current chrome ring finish. The 220 is the old school standard. Hard just to turn it over with standard tension rings until it get broken in…

Is the brush to finish it off, a ball hone..?

[Tom R]

What is your taper..?

No taper. He did do a good job of keeping them straight.
As tempted as I am to “fix”  the crosshatch with a ball hone, I think the best thing is to just scrub them up, and put it back together so I don’t have to look at it anymore.

Do you know what grit stones were used for your chrome rings final finish..?
You can use a magnifying glass to see if it’s been plateaued hone as mentioned by Will…
It will look similar to a tiny pyramid with the top filed flat..millennium technology provides plateau honing..

He said 220 to 280 to a brush to finish it off.

280 is a more current chrome ring finish. The 220 is the old school standard. Hard just to turn it over with standard tension rings until it get broken in…

Is the brush to finish it off, a ball hone..?

Not a ball hone…. He said it’s a brush to finish it.
I’ve several ball hones I’ve collected over the years for prepping cylinders. I’d do 6-8 strokes with a 180 followed by another 6-8 strokes with a 320. They come out looking real nice and no smokers yet.
Maybe just a 280 would work better.

[Tracksnblades1]

Perhaps it the brush marks that the pictures are showing..

I like the 0.0009 clearance you measured so I probably wouldn’t do any type of aggressive honing that would increase the diameter. Plateau honing usually uses a few passes with a finer grit to get the desired percentage. US Chrome and Millennium advertises such, but  they specialize in chrome (hard) and nikasil bores. They do cast iron too.
Round and straight are important for long ring life too..

[MRieck]

I'd say the cross hatch angle is off, but I'd have no problem using them.

A little steep it'll be OK. Any idea what grit that was finished with. Sorry just read about the finish.