YXR223 build

[Rat_ranger]

So since I ended up rebuilding the RM to stock, I picked up a cheap no motor YZ250 to stick an XR motor into.

I'm building a 2000 xr motor, 8mm stroke, 66.5mm crf230 piston, atc cylinder for the bigger fins, and undecided on cam.

Starting this out by tearing down the spare crank, and offsetting the rod pin 4mm. I turned a steel plug, pressed it in and welded in 2 spots. Then made a nice fixture from a 6" OD aluminum round 3" long and got to work.

 

[Rat_ranger]

Some slow progress. I think the engine is sitting where I want, made a super basic stand out of scrap to line things up. Cylinder is off getting bored, maybe it'll be ready by spring.

 

[Rat_ranger]

Rear motor mounts are done. Next up are the fronts and when the DOM shows up I'll redo the cradle.

 

[Rat_ranger]

It's a tight fit, but the neck brace clears the head. Tube showed up so next step is to remake the cradle and set up the front mounts.

 

[Rat_ranger]

Cradle is partially welded in, and one side of the head steady is done.

 

[Brodie]

Looks good

 

[Rat_ranger]

Thanks! This should be about my ideal trail bike. Plush suspension, with linear predictable power.

 

[Rat_ranger]

Front mounts are 75% finished. Once that's done its time to start assembly on the motor.

 

[Rat_ranger]

It's been a while but there are updates. Ended up with a stock xr200, swapped better suspension on, and have been riding it.
The stroker build has the motor together, and in the yz chassis. Yesterday I built a stepped header for it. Waiting on an intake boot to figure out the intake set up.

 

[Rat_ranger]

It's a tight fit, gonna have to convert to a cable choke.

 

[Rat_ranger]

Adapted a newer 18" WR wheel with some custom spacers.

 

[Rat_ranger]

Starting work on the airbox and fuel tank. Gotta make templates to figure out size to get the right size of aluminum sheet.

 

[Rat_ranger]

Made a pattern for a custom tank. Used 1/16 backer board since I plan on using 16ga aluminum.

 

[Hurco550]

loving this man. I regret selling my xr200 often. This seems like a best of both worlds project

 

[Rat_ranger]

loving this man. I regret selling my xr200 often. This seems like a best of both worlds project

I've got a stockish xr200 in the background, because I also regretted selling one I had in the past.

The tank is almost ready to test for leaks now. Once that's done I'll mod the airbox to connect to the carb.

 

[Maritime]

Nice progress. looks great.

 

[Rat_ranger]

Thanks, the tank ended up higher capacity than I was thinking at 3.5 gallons. I think I'm going to put fuel cell foam in it to reduce slosh since it won't hurt capacity.

 

[Luugo86]

The tank looks good man, nice work

 

[Rat_ranger]

The tank looks good man, nice work

Thanks, I learned a fair bit making it so I can probably do better in the future.