125-200cc Cr144 cold seize oh my back !!! Advice?!?

My friend Brian is an idiot. He asked to ride my bike today. It's 40 degrees out btw. So I said yeah sure choke it and warm it up real good before you wring it out so it doesn't seize. Well needless to say he didn't let it warm up at all he took off wfo. When he got back he said hey I was in sixth and it fell on its face and locked the back wheel up and I shifted down to third and it finally broke back loose and started up so I took it easy all the way back. He said it ran fine after that but it sounds a little odd to me. Like a temporary cold seize. Should I get my wallet out and order a new top end or could it have been something else? I haven't rode it after that because I don't wanna tear up anything any worse than it may be. Thanks for any input. This is my first experience with this situation as I always warm my stuff up before ripping off. Lol oh and some other info my bike is jetted perfect. Running 32:1 mix and I had a br7es plug in to kinda clean it out a little because the previous owner used klotz at 32:1 and never ran it hard at all. Plan on using a 9 again next ride though. Thanks again.

The only way to see what is what is to tear it down. It's probably going to need a new piston and the cylinder re-plated. Crank might be shot too as it was subjected to a lot of force.

Your friend isn't really a friend unless he steps up an pays for what he broke.

Take the barrel out and inspect it is all you can do!! You might get lucky that the bore isn't too heavily scored but a cold seizure can loosen up however, 9 out of 10 times you'll need a replate and piston/rings. I don't think you've harmed the bottom end but l would flush it out with diesel or kero should metal shavings find it's way in there - good luck!!

Yes daveyblueballs yor mate Brian is a mong. Tear cylinder off n inspect. I'm sure bottom end will be fine jus check it for play. 7 is a hot plug!

Thanks guys. I'll try to tear it down and inspect as soon as I can. I'll let you know what I find. I appreciate it.

at least he told you about the issue
he should at least chip in towards rebuild..

I haven't had time to work on my bike just yet because my wife and I are moving, and I'm workin 7 days a week right now but when I do get it tore apart I'm thinkin about maybe having the head cut and some port work done to it. To whom should I have do my port work and head work? I don't care about reliability because I only ride like 3 times a year. Oh and I'm kinda weird on how I like my power and too. I don't care if it has any bottom end at all I want a hard hit with midrange that will pull my arms off and a top end that never stops pulling. I plan on using a Husqvarna piston also unless I could get more power with a different piston. Thanks again guys. All comments are appreciated very much.

Racing mine below 40 degrees f, I'll use some thin cardboard to block off a rad. Fits under the plastic guards and lets the engine keep its heat.

Well, you may not want to cut the head. Cutting the head will increase compression and increase bottom end at the price of less top end rev out. Cutting the head will also most likely require race gas also.
If I run my 144 with a stock .5mm base gasket it requires 50% face gas and hot hard on the bottom (hard, for a 144 anyway!). and signs off early.

Call Eric Gorr and see if he is still doing 125 port work.

Okay so finally I managed to find the time to load my bike up from work and bring it home. Unfortunately though I only had time to pull the pipe off and have a look at the piston. It was scratched up a little. I could barely feel the marks when I stuck my finger through the exhaust ports. I used my phone for a light and I could also see some scarring at 10 o'clock and 2 o'clock if the exhaust port is 6 o'clock. I hope that makes sense. Lol I did get the chance to snap a picture just as my phone died. Bike still has compression and runs as it always did. I put the br9es back in. Should I rebuild before riding again or is it cool if I ride it this weekend? I don't want to take a chance of catastrophic failure but if it's not gonna hurt to putt around I would love to ride this little beast. Sorry the picture isn't the best but the ring seemed fine and I couldn't feel a lip on the exhaust port anywhere either.

From what I can see that piston is due for a trip to the scrap bin. Ive got better looking items with 50 hours on them,
Time to pull the top end or at least the head to look for damage.

I've tried to call Eric Gorr like 80,000 times and no answer. I called pro circuit about a replate and port work and they wanted 650 plus a piston and rings. The guy I talked to there was kind of a dick. Then I called finish line engines, this guy was about to dyno a bike but he stopped what he was doing and took the time to explain what I needed to do to send him my top end and walked me through all the powerband choices. He said I'd be lookin at just under 400 bucks and 2 and a half weeks worst case scenario to replate and port my cylinder. So have any of you guys heard of them? Any experience with them? I looked for reviews but couldn't find any.

Is that a crack between the exhaust ports? I can barely feel it. Other than the scarring that's all I've found so far. I can still see cross hatches and can't feel the scars with my finger nails.

I pulled the cylinder and piston. Piston is totaled and so is my exhaust port bridge.

Okay so I sent it to finish line engines in Wisconsin. He ported it and replayed it. I bought a wossner piston from halls. I put it together and and broke it in through 4 heat cycles. After I decided to let er rip after it was warmed up of course and the first time I got it up to full tilt in in sixth it seized again. I tore it apart and the rod is good no play except for side to side. The bike ran fine no bogs anywhere through the rpm range. The piston and cylinder looked the same as last time except the port bridge wasn't cracked. I had a 9 plug in with klotz at 32:1 93 octane. The coolant was circulating good. I checked the water pump and it fine. The plug looked a little lean but not super lean. Would that little bit of wot with a lean main jet cause this? I really need help.