2010 KX250F - back from the dead

Edited Date/Time 10/23/2018 3:29pm















Here she was the day after I brought her home. A 2010 KX250F with Akrapovic exhaust and Athena 290 kit. Unloved and forgotten. Didn't start, had little to none compression, oily and dirty and of course serviced every 5 hours. Or not. Although I must say the red spoke shields sealed the deal for me.

I set off with a goal to get the bike to start and take it from there. My goal was never to sink shed loads of cash in to it but to clean it up and restore it to its former glory while maintaining a budget. This was my first dirt bike in 10 years and my first thumper so I took the project as a learning as well.





Starting to take it apart:

























New seat cover fitted:









Here we go with the engine removal:










No wonder it didn't start. So much for the easy fix and maintaining a budget. Luckily, the valve hadn't hit the piston (at least not at speed).




The cleaning begins (the fun part):











Exhaust parts cleaned:





















Carb gets a polish:















Linkage gets a polish and new lower shock bearing installed:
















Rear caliper refurbished:



















Frame cleaned and polished (before photos lost):













Rear shock cleaned and shock spring painted:









New SS Intake valve kit fitted:









New 83mm piston kit fitted:











Putting it back together:



























































New tyres installed, letters painted and wheels dipped:



















Used plastic kit bought and installed. Bike finished!:























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10/23/2018 3:07pm Edited Date/Time 10/23/2018 3:19pm
So the issue with the bike not starting was that a valve collet had broken and lodged itself between the valve spring retainer and the valve bucket. I believe this was/is a somewhat common issue with the KX250F's from around this time and this bike was lucky that it seems to have broken when the previous owner tried to start it.

After fixing the valves and fitted a new piston the bike started up pretty much first kick. Although I had some fine tuning to do with the carb and the idle was set too low so before I figured that out the bike died as soon as I hit the throttle.

Parts replaced:

* SS intake valve kit and springs. All valves out of tolerance so shimmed all 4 to spec.
* Piston kit.
* Camchain.
* Top end gasket kit.
* Engine fill plug.
* Lower shock bushing.
* Front and rear sprocket.
* Chain block and swing arm chain slide.
* Front fork oil seals.
* Left side foot peg.
* Plastic kit incl. graphics.
* Grips.
* Tires.

Previously missing parts fitted:

* OEM skid plate and engine cover guards.
* Rear caliper guard.
* Rear disc guard.
* Hot Start lever.
* Various nuts and bolts.

Time spent from start to finish: around 1 month.

The bike looked to be in a much worse condition than it was on the inside. The piston in the bike had very little wear on it. Since I didn't know how the bike had been serviced before I replaced the whole top end as a precautionary measure.

The con rod big end, small end as well as the clutch plates measured well within service spec so I believe the bike was just un-cared for but not ridden very much/hard.

I sold the bike not long ago but the little time I used it was a blast. The 290 kit makes the bike feel so powerful.

Will post future builds later on. Hopefully someone finds inspiration in these "low-cost-hard-work" rebuilds. I try to manage on a budget without cheating on quality parts and doing all the work right, replacing what needs to be replaced and fix what can be fixed.

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