Remember weight is important. Be sure to have the correct spring rate for you weight. This bike is fitted with springs suitable for a rider of weight around 70kg.
Having said that I found that the rear shock was too hard with the rebound damping seemingly non-existent. So I purchased a a cheap aftermarket shock (around 200usd) with the correct spring rate and only adjustable rebound damping. This made a world of difference both on track and road making the bike less bumpy or fidgety. I got my rear shock from a Taiwanese dealer who designed the part especially for the bike. WL motors
was the source for all my parts. He also ships overseas.
That was the easy part.
For the front you either spend a lot of money on customising the front end to suit easily available USD forks or slightly less money buying a fork and triple clamp set from a manufacturer here in Taiwan (around 900usd). As you can see I tested it pretty well.
The pics show a combination of the Fastace forks and rear shock.
OR
You could spend considerably less money (about 200usd) but more time tuning the supplied forks.
First you will need to change the supplied springs for some that have the correct spring rate to match your weight.
Next you will need to acquire a wonderful little item called a cartridge emulator. I got mine here. The company is Y.S.S and their product is the PD Fork Valve. The size to fit the CPI SM250 is 29mm the part is PD 290 it fits in perfectly. This is the same size that fits on the Ninja 250 since these two bikes have the same forks. Well, the bore and design (showa) are the same, I doubt the stroke is the same.
Installation is not too difficult requiring some machining and tuning takes some time too. Full instructions on fitting and tuning.
Once fitted and tuned the bikes personality changes completely. The ride becomes softer and the nosedives are reduced significantly.
Just a couple things and you are done. These forks, like any other of the type, will flex. This flexing contributes not only head-shake but also to the bike wanting to wander off a true line. To that end you should get a fork stabiliser/brace. Lastly, to mitigate the head-shake somewhat I dropped the clamps a few cm so the forks poke 5cm out out the top of the clamp.
Pics of Fastace rear combined with tuned standard forks. First pic has a blue circle around the stabiliser.
I got 1st and 2nd place racing two amateur races with this set-up and a I also use it to ride on a daily basis.
