kz650b2A revs and redlines

I've seen some speedos here with both MPH and KPH on them. The older bikes will only have MPH (ones before we converted to the metric system). Mine only has KPH and goes to 220!



Post edited by: rstnick, at: 2007/08/05 22:43

Put a Dyna2000 ignition on the KZ650 the other day. As mentioned in another thread, I always rev the pee out of the thing, and the tach seems only slightly more accurate than the speedo, which is hilariously far-off. I set the rev-limiter to start with @ 9000 (Factory redline). Noticed right away I hit the limiter before engine was peaking-out. Put it @ 10,000, which feels about right; if I hit the limiter now, I was a bit too slow shifting. This bike has a 16-inch wheel on the back I stole off my 900, with a 130/90-16 tire I measured @ 78" around, marking my driveway and lining-up the valvestem with the brake-stay and the ground. This divides to 24.84" diameter. Using the only formula I paid attention to in college trig and the gear ratios from the factory manual, changing the final to 15/42 like I have on it, I get 69.83mph @ 6000rpm. Today, coming back from Cassoday, I hit the rev-limiter in top gear. That's 10,000rpm to the ignition and 11,500 or so on the tach. 10,000 in 5th would figure to 116.37mph. Hmm... I like the gearing like this, but it was pretty easy to hit the limiter @ top-end. Maybe I need some cams to let me bump-up my "redline"...

BTW, this bike is stock except for the turnout mufflers and the 29mm slingshot carbs from a first-year GSXR750.