Best paint option for a CR125 rider rebuild?

Frame? Powdercoat it

Yes I would say powder coating is one way to go, or you can paint it yourself using auto quality base and 2k clear coat. Now you can buy it in cans from a auto paint supplier or paint store and get really good hard surface, oil and gas resistant results at home, it is also easier to "touch" up when it gets scuffs on it and has a nice factory looking shine. This way is much more work than taking it down to you local powder coater however and not for everybody.

There are many high heat engine paints for sale at your local auto store and they may work great; But I have only used PJ1 case paint on my stuff because I just like how it looks and it is very tough stuff if you apply it right. I use the "satin" finish for what I think is a very nice look, they also sell gloss and flat if you prefer. Make sure the temp is over 70 degrees and you shake the can well or it will spit and make it very hard to get a smooth job, also let it dry for like 2 weeks not the 1 day the can says. I have this on all my "retro" bikes and my 03 yz 125 rider has been holding up well except for the under cases and front of pipe but those areas will get worn no matter what paint you use, just touch it up.

Wow - nice job MXM!
Dan I agree with the guys, powdercoat it. Its just a tougher, harder finish.
And post us some pics guy!

I prefer automotive grade single stage urethane applied over an epoxy primer. It allows for easy repairs or refinishing in the future if it is a bike you plan on riding and racing. It holds up just as well as a clear coated finish. Also, it has a better appearance for a proper restoration as you can still see the details of all the welds and such if that means anything to you.

But, by the time you get your frame sandblasted and purchase the necessary materials, you will have spent as much if not more than it would cost to have it powder coated. Powder coating is extremely durable but an absolute pain in the ass to do any repairs to should the need arise.

Newmann, so you use a single stage (base and clear together) urethane instead of base then clear. I always avoided the single stage stuff because I thought the base then clear was more work but was stronger in the end; Does the single stage really go on that much thinner than two stage jobs even though the single is thicker to start? Also we may be talking about different ways of painting, if you are using a spray gun system or rattle cans; I have been using the urethane base with the 2k clear from cans.

Single stage is just that, a direct gloss catalyzed urethane finish. You can clear over it to add additional UV resistance but as far as durability and chip resistance, more paint/clear isn't always better. Metallic colors will benefit from clear, but most solid colors that you would be painting a frame with will be just fine. Single stage urethane will have the same basic viscosity as clear so it sprays similar. Painting a frame takes a good bit of effort, in and around all of that tubing, gussets and misc. brackets. Being able to avoid additional unnecessary coats of paint isn't a bad thing....

Which clear are you using from a rattle can? BASF makes a 2K clear in a can that works great. Expensive, but it's a real urethane clear.

Also, having a mixing room full of auto paint at your disposal may have me a bit biased. Having to go out and buy everything to paint a single frame would not be cost effective.

Ya every frame I have to paint is a on off and requires supply's for each as separate units. I can get what I need for about $100, 2 cans of custom mix or oem urethane base put into a can for about $30 each and two cans of the spray max urethane 2k is about $25 per can. After you add in the sand paper, wire brushes, cleaner, supply's to make a temp paint booth and all the hard work to do it, it would be cheaper and easier to powder coat, but I really like to see my own work after it's done and feel proud of what I accomplished. I always do things the hard way, one habit I wish to break.