Should I run these cylinders or not?

[Guest]

Hello, I am currently restoring my bike and have come to the point of engine reassembly. The head has been completely rebuilt by APE, new rod bearings,crank balanced and new bearings, I am using the stock Pistons as they measure in tolerance and good shape, using new rings. Took my cylinders to the local shop to be ball honed. I was concerned about the condition of these cylinders and so was the shop. This is not going to be a race bike, just an old girlfriend. I have a couple photos showing marks I can feel with my fingernail. The shop said one jug had a crack? My question is this, should I run this thing, or hit eBay for another? Options? I thought about bore to 771, or put new jugs? I am not a rider with deep pockets. I need experienced minds to help me take a next step. Tired of this thing in pieces. Thank you

[Glendeco]

This is the other pick since I can only post one per post. Well, trying to post it anyhow.

[Glendeco]

image.jpgI got it up now. What I'm pointing at can be felt with my fingernail, the other ugly stuff is smooth.

[tkent02]

Rust damage from sitting forever with the outer pistons down and the inner ones up. Probably sat with the head off open to the atmosphere and moisture, or at least with the spark plugs out.
I'd run it if I was on a budget or in a hurry. The rings will smooth it out somewhat. Probably run OK for a while.
If I wanted it to run perfectly forever, then not. If it's cracked, then definitely not.

Throw a set of 850 jugs and pistons in it. Cheap and easy 15% increase in displacement, or thereabouts.

I have both 750 and 850 cylinders here.

[Steve]

I thought about bore to 771, ...

One might rightfully assume that your bike currently displaces a bit less than 771, but some clues would certainly be nice.

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[Glendeco]

Yea, the cases were destroyed when someone before me was hammering to split them apart during their "rebuild" I'm thinking I should probably not cut a corner at this point. Fellow riders say run that money pit like you stole it.

[Glendeco]

One might rightfully assume that your bike currently displaces a bit less than 771, but some clues would certainly be nice.

.

Sorry, it's a 1986 gsxr 750. I have a friend that posts here advised me that there is some Yoda knowledge on this type of thing. Just didn't want to say it was for a GSX for obvious reasons Harley riders don't like Buell 1125r which is my main steed currently. Been working on the GSX for about 3 yrs. Little by little.

[tkent02]

Sorry, it's a 1986 gsxr 750. I have a friend that posts here advised me that there is some Yoda knowledge on this type of thing. Just didn't want to say it was for a GSX for obvious reasons Harley riders don't like Buell 1125r which is my main steed currently. Been working on the GSX for about 3 yrs. Little by little.

Haven't looked, but I bet used GSXR 750 cylinders are easy to find as well.

[Steve]

Knowing that it's for a newer 4-valve 750 negates tkent's suggestion to use 850 cylinders.

Again, details are handy. We may cater to and specialize in the GS line, but there are several here who also know about the GSX line and can help. The problem is when we don't know what bike we are discussing, so it's possible that some wrong suggestions might be made.

At least you have a location listed, we know not to send you to some European vendor.
Now, please take a moment or three and generate a signature that lists your bike(s). We are not afraid of you also having your Buell listed there. If you notice in my sig, there are three bikes that are not GSes, it's nice to see the variety sometimes.

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[Glendeco]

Noted. I have changed my profile a bit, gonna go for a ride now as willmrx already has his helmet on. Thanks everyone in advance for the info.20161001_154025.jpg