1982 XS650 Heritage Special highway RPMs.

[aldo5468]

PamcoPete shared an interactive spreadsheet for tire size, sprocket size and road speed some time ago that you may be able to find and download. I couldn't attach it to this reply, but playing with your info shows that a 17/36 sprocket combo and 16" rear would expect about 4650 rpm at 100kmh (61.6 mph). Similarly, 17/34 sprocket combo would show about 4400 rpm, and 17/32 combo would show about 4135. His spreadsheet uses mph, so these results are ratioed up from the 60 mph values to 61.6. So this also suggests that 5000 rpm at 100kmh is too high, even for the 17/36 combo. Make sure you're using motorcycle-specific oil - some of the automotive ones have friction modifiers that may promote some clutch slippage. Also ensure that your tach cable is well lubed.

 

[itsseanjohn]

It wouldn't be exactly 5k, but the tach is so shaky at those speeds that you can't tell exactly anyways. I need to get a new gasket for the tach I think

 

[Phail]

I'm running 18/30 on mine but it's a stripped down chopper and I'm pretty light. I love the combo. I was cruzing down the road at 90MPH the other day (gps) with no problem. I usually cruze at 70mph. 55 feels like 25.

 

[pamcopete]

Here is a Excel spreadsheet with all combinations of sprockets, gears and wheel sizes. No cookies! This spreadsheet uses rolling distance instead of wheel diameter or circumference because there is no way to measure the effective diameter or circumference of a motorcycle tire.

www.amckayltd.com/xs650revs.xls