Ok I know this is an ATV forum but I already have an account and several other overhaul project threads on this site. I picked this up today for $50 plus the trade of a BMX bike I would value between $100-$150. So I basically got it for under $200, I think I did alright.

The kid ran it too lean, on top of the fact the person he bought it from told him it needed top end work and he rode it anyway. Only thing that scares me is the fact the kick start lever moves back and forth when you rotate the crank shaft by hand. I have all the pieces it's just a matter of labor, has an FMF Power Core II and Gold Series fatty on it.

I'm 50/50 between investing to make a running machine to sell or parting it out. I tried to take the best top end photos I could, a buddie told me that it can not be honed out because it ate through the coating (assuming the chrome?) and that the head needs to be sent out to be rechromed, the good thing is it hasn't been bored as we know of. Does not look like the sleeve can be pushed out so it would need to be put on a lathe correct? Piston looks like its toasted There are a few drops of water in the head from moving it in snow those are not burn holes. If I dropped $125 on a new piston, rings, and a few gaskets what is the downside of installing it in a bad jug like this besides performance loss? Would I damage the new piston and rings or wear them faster in this jug? I'm assuming it would give me enough compression to get it running and sell it.

My brother has a 1997 CR125R, and supposedly 1997 was the last year the frame was steel and the motor was better than the 98' and up. Is this true for the CR80's? Are there any good things about this year that will help me sell it? Not sure if this is an 80R or 80RB

Mind the mess in the background, this month has been hectic.

 

 

I would slam it together and don't look back.

Are you sure the jug is coated? From the pictures it does not look like it?

You just don't need a ton of compression to make a two stroke run great like you need with a 4 stroke.

Looks like a cool little project!!!

 

Maybe not, but if it is coated or plated then I can not bore the jug out and reinstall a new one can I? I've requested some quotes on having it put on a lathe, but are the sleeves machine pressed in with hydraulics or can I install a new one myself once the old one is removed? Still debating weather to just replace the piston and not touch the head.

 

The first thing you need to do is find out if it is coated. If not I would just hone it, re-ring it, put a new piston in it and put it back together and go have fun.

Or you could re-coat it or buy a new jug. I would do whatever is cheaper. It won't have a sleeve (or I'm 90% certain it won't).

I bet a used or new jug would not be that much. It just depends on how involved you want to get.

 

What is a good way to determine weather it's coated or not? Ebay replating prices for my model are $200

All the jugs on ebay say they need to be replated. I'm willing to get as involved as it takes to get the job done for the least amount of $ = largest profit. This is a profit project so I have some $ to spend on my LT250R

They sell "sleeves" for CR80's so I'm assuming it's sleeved.

 

You can take it to a Honda dealer and see what they say. Sounds like they are coated though if that is what they say on Ebay.

It's hard to tell from the pictures but from what I can tell I would just hone it and go if you just want a return on your $$$'s.

 

Looks like I just need to measure my piston tomorrow and then buy a new one which is around $125, and the "flex-honing" tool is $25. So I just may make my $200 budget after all. I will spend a good hunk of time tomorrow trying to get some really good photos of the inside of that cylinder for better opinions on weather it's honable.

 

Measure the piston, if the cylinder is gouged pretty bad go 2sizes up from whatever size piston is in it. Bring the jug with the new piston and rings to a machine shop. They will bore and hone it for 50.00 or so slap it together and ride. It ain't that bad. Try to get a better pic of the numbers on the top the piston so we can see what size it is.

 

$50 you say? That would be sweet, but if these cr80 cylinders are plated I thought you can not bore them without replating after? Looks like the piston kit sizes I have available to purchase are 46mm, 47mm, 47.5mm, 48mm, 49mm, & 52mm (DennisKirk)

This one service on ebay wants $240 to install a new sleeve (sleeve & shipping included)

Pictures are coming tonight for sure, it's a good thing you will be able to identify the piston from the numbers on top because I don't think I have a micrometer here.