Cylinder Question

[Rd]

I stuck a magnet in the exhuast port of my newly purchased 1990 K5 and it stuck to the back cylinder wall. I would assume this means that somewhere a PO has installed a cast iron  liner. Is this correct? The motor will probably be getting torn down this weekend.

[DoldGuy]

Rd,
If the magnet sticks it has been sleeved.

The name RD, Yamaha Twin guy too?
DoldGuy

[BDI]

Although there's a good chance your cylinder may be sleeved a magnet will stick to the stock plating.

[Rd]

When it is apart I will post some pics. Thanks guys for the info>

Doldguy
Yeah I raced RZ's in the 80's. A 500 RZ would be nice, but the prices are crazy now.

[BDI]

If it's sticking to the stock plating it will only be a light stick. If it's a cast iron sleeve it will stick with authority.

[Rd]

Got it apart today, it is sleeved and has a 87mm piston in it. I kind of expected stuff like this. The bike was in rough shape and I made the guy an offer, not expecting him to take it.

What are my option? Once a cylinder has been sleeved can you ever have non linered plated bore? I would not think so. Wiseco offers an oversized piston, but I would rather not have a sleeved motor. 

[cbxracer30]

As long as the sleeve was put in correctly and the ports were matched up , there is nothing wrong with a sleeved cylinder. The honda 5 always had sleeved cylinder . Also US Chrome can now nikasil the sleeved cylinders, my buddy had one done and raced it for years.CBX

[Rd]

CBX what type of bike was your buddies? I have seen Honda CR500s advertised for sale with plated cylinders.
I saw on the US chrome website that they could plate a sleeved cylinder. One of my concerns is heat transfer issues.
If you plate a sleeved cylinder do you set up the clearance for the plated finish or the steel liner?
I need to split the cases and check out everything in the bottom end before spending money on parts, so I will have some time to decide which direction to go.

The ports seem to transition to the liner well and the PO said he never had an overheating issue. He also rode the bike with the pipe cracked so bad it should have broke in half and he seemed suprised when I told him the pipe was busted. The cloud of smoke coming from under the fuel tank should have been a clue something was wrong.

[BDI]

Just make sure you warm it up good before riding to avoid cold seize.

[blueoval]

Rd, where are you from?  California?  B.O.

[Rd]

Rd, where are you from?  California?  B.O.

Clemson  South Carolina