Question for the Honda guru

[atc500x]

I saw this a long time ago but never take time to take a picture.I changed the timming chain on my friend 250es and finally took a picture.Why the 250es and sx case have the slot ready to switch the chain slider? The slot is already molded to fit the rear slider on the front and bolt the front to the rear.For me it's like another model use the same case...but....if you change the slider,the engine must turn on the counterclockwise.The cam must be different......The automatic chain adjuster mus be behind of the cylinder instead of front
Or the case was used on a chain drive model???

???????????????????????

161674

[Hurricane635]

Not claiming to be a guru, but the sx, 350x, and I think trx350 share clutch cover and center case gaskets. Also the right center cases appear to be the same castings.

[atc500x]

Thanks you !