Ok so I have my 86 trx pretty well built. I race xc. I noticed a crack right behind both bottom motor mounts when I first got it. So I tore it all down and welded the cracks and installed a puma gusset kit and had it fresh powder coated. After a few good rides on all this I believe there is a very small 1/8 crack starting right behind the bottom mount where it was befor. I didn't even run it as hard as I could of. My question is can you give me any advice on a aftermarket frame? Are they strong? Can I get one for 1500$ will all my stuff fit it ok? Like my 450r rear end? Should I just retire my 250r and make it a show piece or will an aftermarket frame be way better? Would love to do a 330 kit but not in a 33 year old frame.
Aftermarket frames are strong - much stronger than stock, but they are still metal and with abuse they can still crack as well.
Hard punishing racing and weight will still stress it, especially if you happen to be over 180lbs.
Can you find one for 1500? - not likely - your best bet is to find one complete its usually cheaper that way, but don't forget most aftermarket
frames are still 15-25 years old unless you buy new. IMO it's all about budget. If you can afford a new frame, I'd go that way because even if you
retire the 250R and go to any 4-stroke, those frames are stock mild steel as well and starting to get older as well.