New Cylinder ??

[MattScott]

I’m new here so bear with me. I recently bought a used 98’ KDX200. The starts fist kick every time almost but runs ok, not great. I want to rebuild the top end just to give me peace of mind. I ordered a weisco top end rebuild kit with 66mm stock piston. I was wondering if I can buy an oem cylinder instead of sending mine off to be replated, and if so where? If not where do I sent for replating and how long does it take? Also, while I have the top off, is there anything I can do to the bottom end to freshen it up without rebuilding it? Im not ready for all that. Thanks for any info. Also any suggestions on a decent bore gauge that’s not too expensive??

[SS109]

Ok, I'll try to address each question...

"I was wondering if I can buy an oem cylinder..." Sadly, no, unless you just happen to stumble across an NOS one in someones stash of parts somewhere. They've been out of production for a while now.

"If not where do I sent for replating and how long does it take?" Millenium (https://www.millennium-tech.net/) is my go to place for my plating needs. I've used them many times and always been happy with the work. Normally takes a few weeks but last I heard things are backed up a bit (busy season + covid) and could be 6-8 weeks. Call to know for sure.

"...is there anything I can do to the bottom end to freshen it up without rebuilding it?" No, there really isn't. All the bearings, bushings, and thrust washers that wear can't be accessed without splitting the cases. You can replace seals that can been seen from the outside, check/service your clutch, water pump, kick start mechanism, and shift mechanism but that's about it.

"Also any suggestions on a decent bore gauge that’s not too expensive?" Sorry, I do not.

[KDXGarage]

PowerSeal USA or Millenium

Get the bottom end checked by a pro or just go ahead and bite the bullet, getting the crankshaft connectind rod, bearings, etc. replaced.

[MattScott]

Ok thanks. Looks like I’ll be sending it off for a replate.

[KDXGarage]

I'd rather have a good condition used cylinder replated than a new one. The aftermarket plating from the two companies I mentioned is often regarded as better than the stock plating.

[pumpguy]

To answer your question about a bore gauge, a set of telescope gauges and a 2 to 3" micrometer will do the job and are not really that expensive. Shop around, you can find decent quality import tools. You don't need to get top quality, you're not measuring parts for the space shuttle or a nuclear submarine.

If you see yourself messing around with motorcycles for the foreseeable future, these tools will come in handy more often than you'd think.

[billie_morini]

I, too, prefer modern plating formula from Millennium. But, new OEM cylinders are available. They'll cost you two or more times the price of a modern plating job.

Anyone interested in OEM cylinder can get one here for about $700 (US)
https://www.cheapcycleparts.com/oempart ... d-cylinder

[KDXGarage]

billie_morini, do you know for sure that they have them or can get them?

[GOT WOODS?]

I'm stuck on the cylinder replating thingy.... Do you know that you need a replate or are you assuming that you need one because you are replacing the piston? If the walls are good and they are in spec, you don't need to get a replate every time you throw a piston and a set of rings in there. You may already know this but just checking.... Usually the plating questions are preceded by a great story of woe and misery about how you fried the top end and had to push the bike home 10 miles and up 3000 feet to your mountaintop abode..... I'm not hearing this here..... are you holding out on us?