Go the the Ninja250.org website and check out a tech article on installing a bike computer. Those guys say the Sigma wired bike computers are the best ones for the job. Ninja 250s are notorious for bad speedos.
__________________
John
'09 Cannondale CAAD9 - Team Latitude/ABRT Special.
'04 Lemond Victorie Ti
'98 IF Crown Jewel (dead)
'92 Trek2100 (TT)
'50 something Gino Bartali (fixer)
'02 Ducati ST4s (Moto-Ref mount)
My Blog