220 Piston Skirt Exploded

[Jones]

Hey fellow riders,

My 2001 220 got stolen last year so I saved up enough to replace it with a nice 1997 220 recently. On my 4th or 5th ride on this new bike I heard a ding and the bike went quiet. Unfortunately I was miles from the trailhead and between pushing and getting towed by a UTV it took a few hours to get back to my truck.

When I opened up the top-end the piston skirt had completely exploded and shards of metal were everywhere, the connecting rod won't budge. I dont have a case splitter, so I haven't opened up the crank yet, is it likely completely hosed? I'm wondering if replacing the crank is a job that's relatively straightforward and something I can do myself, or if I should try to ship it off somewhere to get it done perfectly. I saw a few posts on KDX Rider and Thumpertalk referencing various crank specialists like Cooksey Crank. I've done all maintenance and most of the repairs for the KDX i owned in the past, nothing more technical than replacing top-end and replacing clutch plates / basket. Is this something I could do?

[Jones]

Sorry I realize this probably shouldn't be in the introductions section, even though its my first time posting it's not really an intro.

[KDXGarage]

Welcome to kdxrider.net.

Sorry to hear of your bike's troubles.

You may want to look around on here at older threads, as several people have shown tips and advice on splitting the cases.

If the crankshaft halves are not damaged, then it may be a great time to have the crankshaft rebuilt with a new connecting rod, bearing and washers.

Cylinders can be repaired and replated by PowerSeal USA or Millenium Technologies. They can sell you a new piston and rings kit to match it properly.

Read up on what others have done and see if it is a task you want to do.

And one last thing, a service manual will be a huge help, whether OEM or Cyclepedia.

[SS109]

Welcome to kdxrider.net.

Sorry to hear of your bike's troubles.

You may want to look around on here at older threads, as several people have shown tips and advice on splitting the cases.

If the crankshaft halves are not damaged, then it may be a great time to have the crankshaft rebuilt with a new connecting rod, bearing and washers.

Cylinders can be repaired and replated by PowerSeal USA or Millenium Technologies. They can sell you a new piston and rings kit to match it properly.

Read up on what others have done and see if it is a task you want to do.

And one last thing, a service manual will be a huge help, whether OEM or Cyclepedia.

I agree 100% with what he said!

The only thing I'll add is to NEVER use a cast piston in a KDX220! Oh, one other thing, Cooksey doesn't do cranks anymore unless he's doing a full engine rebuild for you. I now recommend Crankworks in AZ.

[Tyl3r]

I had the same thing happen to my 220. I split the cases and had the crank rebuilt by Millennium Technologies who also repaired and replated my cylinder. When I did mine, it was the first time I had ever went that far into a motor before only top ends...it wasn't as bad as I thought. There is a thread on here that takes you through all the steps and it really is a breeze. The FSM is definitely good to have too if you can get one (found fairly easily through a google search). I also had to replace my head, it got chunked up pretty good from the piston pieces in there. This is how mine looked if you are curious: viewtopic.php?p=178350#p178350

[bufftester]

Getting the engine apart is relatively easy. Still a few places that can rebuild cranks as mentioned above. You will need to replace the main bearings and seals. Even if you think you can get them cleaned out change them. I alsways advocate that if you have to tear the halves apart, its a great time to replace all bearings, seals, water pump seal, O-rings, etc. It's already apart, and the last thing you want to do is rebuild part of the motor only to have to turn around a week later to replace some other old part.

[Molly's 70]

Millenium did a fantastic job of repairing my cylinder.

[doakley]

Sorry to hear of the piston failure but if it was a stock piston, it is a known problem. If you can rebuild a clutch and remove/replace a top end, you can split the cases and do the reassembly yourself. A few special tools needed but worth the investment in tools. I'd strongly recommend replacing all seals, bearings, etc while you have it apart. FWIW my preference is Millennium with a Weisco piston, but that's just my preference based on a history of good service. I wouldn't attempt this without a good service manual and a torque wrench though, if I didn't already have them.

[kdxdazz]

I know not an apples to apples comparison but 20 years ago I had a wr200 that broke the skirt off the piston, it was only at idle when this happened, I pulled of the top end, turned the bike upside down and hosed out all the aluminium with high pressure kerosene, but it back together and rode it for the next 3 years with zero issues

[Jones]

Thank you all for the advice, its much appreciated! I'm ordering a case splitter today and will get to work.