KDX 220 Project Bike

[Lunchbox]

Hi guys! So in my English class, we started a project called 20 time, which is based off a concept pioneered by Google where they give their employees 20% of their time at work for their own projects. Every week, we take a class period to work on these projects. Those of us that can't do their projects in class, such as myself, do the work outside of class and then do the documentation during class. That's where this forum comes in. I decided to rebuild the engine of a bike my dad (umberto on here) had. It's a 2001 KDX 220 engine in a 2003 KX 250 frame. It recently wore out from lots of use and poor maintenance by the previous owner,  so my das recommended I fix it to learn how to. It sat there for a while due to me being busy, and then this project came around. It was the perfect opportunity for me to do this. I did most of the work, my dad simply handed me tools and told me what to do when I didn't know. So here goes:

The bike as it sat:

Most of the goodies from it (suspension, rims, seat) were swapped with other bikes we have, so it's not as pretty as it used to be.

Part way through the process:

Fuel tank, shrouds, seat, pipe, silencer removed, subframe disconnected and set back.

With the engine removed:

Chain and radiators have also been removed

The engine:

Other than being a bit dirty, it's not bad from the outside.

Engine apart:

I had to pull the side off to get the KIPS linkage off. My dad had never taken a KDX engine apart, so it was a bit of a learning experience for him too. The cylinder is worn but not scratched. We've sent it off to Millenium Technologies to get it honed and recoated. It'll get a new piston and rings as well as the other important stuff like gaskets, clips, and bearings.

[umberto]

Child labor is good, you should try it.   

[kmc14]

I have a Kdx 220 cylinder at millennium for replate, porting and head cut. I'm told the porting makes a big difference on the Kdx. I'll let you know the difference.

[umberto]

Please keep me posted on the results. 

[Danger4u2]

If you want to paint the frame I'll offer a free sand blast.

[kmc14]

We have a group of friends that are still riding and I'm usually the guinea pig on things but I paid $280 to have a frame done with a $40 discount for a bad job. I didn't know you could get dry spots and runs with powder coat. It actually flaked off with little to no rub. Would like to find someone to do a decent job?

[Lunchbox]

If you want to paint the frame I'll offer a free sand blast.

Thank you very much for the offer, but when my dad bought it he stripped the frame and repainted it. It's still in really good shape.

[umberto]

We have a group of friends that are still riding and I'm usually the guinea pig on things but I paid $280 to have a frame done with a $40 discount for a bad job. I didn't know you could get dry spots and runs with powder coat. It actually flaked off with little to no rub. Would like to find someone to do a decent job?

I'm not sure if he's still doing it, but alward25 was powder coating frames for a reasonable price. You might shoot him a PM.

[Lunchbox]

The cylinder is on its way back. We actually ended up sending two that we had, one from the bike and one from the extra parts we got with it. The extra one had been bored out, worn out, and is no longer circular, but the one from the bike was in fairly good shape and is getting replated

[Lunchbox]

While the cylinder is out, I worked on the radiators. There was a piece of galvanized steel pipe connecting two hoses where the hoses had to be zip-tied to the frame, and it was causing corrosion.

I washed out the radiators to clear the corroded material from them, but luckily there wasn't that much. Here they are drying:

They're not in amazing condition, but it's hard to find any that are for a good price.
While they were drying, I cut a new piece of aluminum pipe to replace the steel one.


Pipe cutter:

[sandblaster]

Nice job 

[Lunchbox]

Nice job 

Thanks!

[Lunchbox]

Not much progress on the bike so far. New rims came in the other day, as the others were pretty ratty. I'll be taking the old spokes and hubs and putting them on the new rims this weekend. The cylinder has not arrived yet. Other than that, I've just done a little minor cleaning to prep to put it back together.

[Lunchbox]

Part 4: The Great Rebuild
The main part of the project is here: the engine rebuild. Everything finally came in, and I was able to put it back together.

Here are the parts:

Bearing and clips:


Brand new gaskets:


The rings:


The new piston:


Freshly sand blasted cylinder:


The old ugly piston:

I removed the clips, pulled out the rod, removed the piston, and then took out the old bearing.

The new piston (neither old nor ugly):

Same process, just reversed. I put in the freshly oiled bearing, put the rings on the piston, put the piston on, put the rod through, and the attached the clips to hold the rod in. Then, I slid the gasket over the cylinder.


After that I added the cylinder (after oiling the inside of it). It went on surprisingly easily.


Some corrosion from the electronics side, which I cleaned off.


The head:

The head gasket was a total pain to put on, but at least I won't have to worry about it coming off. After putting the head on, I torqued all the nuts to the value specified in the manual.

All assembled and ready to be washed:


Mid-wash. The magical foaming de-gunker stuff is great.


Back in the bike:


I couldn't start the bike because somebody forgot to order a coolant pump gasket

Additionally, I rebuilt the wheels, because they were ugly. I popped off the the tires and tubes, then I unbolted the spokes:


They were covered in this ugly car undercoating, so I cleaned them off with a Scotchbrite pad. Then I polished them.


Afterwords, I put them into the new Tusk rims. I trued them up so that the wheel didn't wobble, and then torqued them to 19 ft lbs.


I put in the bead lock, the rubber strip, and then remounted the tubes and tires. Then I put them on the bike and aired them up.


Notice also the '09 kx250f fork guards.

[umberto]

I couldn't start the bike because somebody forgot to order a coolant pump gasket

Ouch!