New guy with a seized 97 kx 250

Well guys I'm fairly new to dirt bikes and completly new to working on dirt bike engines. I bought a 97 kx 250 from my dads friend for 900. It was well maintained from what he said. I cleaned the air filter and made sure every time that I premixed exactly 32:1 with 91 octane shell gas and Kawasaki 2 stroke race oil. I rode it maybe 10 hours throught 5 days. It ran amazing. I was going down a gravel road in 5th gear when it just died and locked up. The kick starter wouldn't budge and it only rolls in neutral. Me and my friend took the engine out of the bike and started to tear into it. We're at the point now that we need to take the flywheel off and get the cylinder off to split the case. We can't get the flywheel off because we don't have a puller and we cans manage to get the cylinder off either. My friend thinks the piston is stuck to it. I'm thinking of taking it to a local shop to get the flywheel off and see what he I thinks about the cylinder. I'm also curious as to what I should replace. I'm thinking the cylinder needs bored or re-sleeved or some thing, a new piston kit, crank shaft, maybe a clutch kit, all new gaskets, and maybe all new circlips? I know weve screwed a few up already.

Any input on parts I'll need and where to get them or any input at all would be greatly appreciated. Also anybody know why my bike locked up? When we drained the oil it was a milky brown.

Well I got the cylinder and flywheel off. The guy that took the flywheel off said the cylinder needs replated. He also said it was the crankshaft that failed. I found a wisco complete bottom end kit for $261. Anybody have any luck with this? Also what's a good piston to put in it?

If your crank is OEM then have it rebuilt with a PRO-X rod kit. Do a search and you see plenty of wiseco crank failures.

Keep scouring ebay  for an OEM crank and I am sure you can find a good used one if you do not want to rebuild yours. 

dont touch anything wiseco.
for replating you can either steel sleeve your cylinder orrrr you can get it plated either works well.

The mechanic I took my engine to to get the flywheel off made it sound like my only option was to replate the cylinder. Would a bore or sleeve be cheaper or better? He also said oem was the only way to go. He told me wisco pistons are horrible. As for the crank he said oem would be best as well.

How are the hot rods cranks? My buddy has one in a yz 125 and it's lasted forever but I've seen stories where they've failed after a few hours. I want to rebuild my bike the cheapest possible way but I want it to be reliable as well. If my engine will last as long with a hot rods crank and wisco piston I'd much rather do that than spend twice as much on oem.

Any input is greatly appreciated I'm new to all of this.

It is cheaper to have your OEM crank rebuilt than buying a new crank...It will cost about the same to replate vs sleeve. Replate is the way to go. 

Ok thank you. How would I go about getting my crank rebuilt? I'm not even sure if it's oem. I havnt split the case yet

Oem Prox then hotrods I've had one in my ember all year it seems to be staying well within.tolerance

Is MrCrankshaft a good company to go through to get it rebuilt? He said it would be about 160 to get it rebuilt and sent back ready to drop in.

Any idea how good Racers Toy Store is a good company. I just got off the phone with them and they said they could rebuild my crank, re plate my cylinder and get me a cast piston that's oem quality for around 500-600 with shipping. This seems like a good deal to me. Any opinions?

if thats with all parts and labor it's not horrible.

if thats with all parts and labor it's not horrible.

Best deal I've found any way I look at it. I'm just wondering about the quality of their work. I'd rather spend a little more for reliability if I have to

$100 variation in pricing? I would want to know an exact number. $500 is good $600 is just what it can be done most anywhere.

$300 for a replate

Rebuild crank $150

Piston kit $110

 

Add another $65 for crank bearings and seal kit.

$100 variation in pricing? I would want to know an exact number. $500 is good $600 is just what it can be done most anywhere.

$300 for a replate

Rebuild crank $150

Piston kit $110

Add another $65 for crank bearings and seal kit.

He said it depends how bad the cylinder is and if I remove the head studs or not

He said it depends how bad the cylinder is and if I remove the head studs or not

Well they will just send it out to plater...cut out the middle man and save a few bucks to buy your crank bearing/seal kit.

Why do you guys seem against going through racers toy store? Is their work not good? I like the idea of sending everything to the same place and getting all my parts back at the same time. And the pricing is close to what you guys are posting..

Standard cylinder plating- $195

Wisco piston kit- $125

Crank rebuild- $145

Thats $564 with a wisco piston. I think I'm going to go with the pro x piston but they dont show the prices on the website. That will be cheaper. But price isn't the reason I want a cast piston. I want a cast piston because a long time family friend that owns his own shop for power sports is so against forged pistons that I don't want to run one. He says they seize easier and something about a pin always coming out and destroying the cylinder.

If wisco is truly superior(reliability wise) feel free to change my mind haha. Thanks for all your input guys.

Thats $465.

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