KDX250SR...
Hi Scotty,
I also have a 1992 KDX250SR. While there are many similarities between the SR model and the 1991-94 model that the Stateside guys refer to... there are also some significant differences.
1. The SR model has an oil pump for the 2T oil... no need to run pre-mix unless the oil pump has been disabled.
2. The SR model uses a 33mm Keihin carb - the US version uses a 38mm (I think) - I'd love to get my hands on a KDX200 35mm carb to see what improvement it would make on my SR.
3. The SR can not use the Wiseco replacement piston kit for a US version KDX250 - it is the same diameter but the wrist pin hole is located at a different location. By the way, I have a brand new Wiseco 607PS piston kit for sale - anyone with a 91-94 KDX250 (US version) interested?
4. I put in a set of Boyesen power reeds (#639) and really like the performance.
5. I replaced the stock fork springs. Just like the US version they are too soft if you weigh over 130 pounds.
6. I run an NGK B7ES plug.
7. If you've got stock gearing on it (14/45) you'll be happier with 14/48. It is not a bad compromise for dirt and street. Top speed is still 135kph.
8. The motor does not have the same KIPS set up as the US version. The SR model only has the small side valves. It does not have the large main valve.
9. It may be difficult to put an aftermarker pipe on the SR model since the stock pipe is held on with a flange and bolts, not springs.
10. I drilled my air box lid full of 1/2" holes to get better airflow into the motor.
11. The US version is heavy, but the SR model is heavier due to the streetable gear - turn signals, horn, etc...
12. The bike turns a bit better when you pull the fork tubes up out of the top clamp by 10mm.
Scotty, I hope these things are helpful for you... stay in touch...