[Ducati] wanted: 916 final drive ratio advice

[peter bonner]

Jules,
There was a time when the thinking was set gearing so that you topped out in
high gear on longest straight at the perfect time, but while that may make
sense riding a small bike with little horsepower, most folks have abandoned
the idea. Instead, consider how well the drive off the various corners
works, and if you only need four or five gears for a given track to get that
perfect drive, then you may be close to optimum gearing. Definitely try
changes, as that is the only way to be sure if you really want to set up for
a certain track. What you don't want is a situation where for several
corners, you had to shift just shortly before getting there, then downshift
again, or a corner where you exit and must shift while leaned over instead
of having a clean run of the throttle. Of course as your corner speed goes
up, then gearing changes may be required again.

Note on the 14/38 combo. Generally, the rule is one odd and one even tooth
sprocket, so the chain gets moved around on the sprockets. Two even tooth
combo means that the chain may create undesirable wear patterns. However in
track use or racing, it probably doesn't matter as much, since you would
change stuff like that more often anyway. (In the 70's, racer John Banks
missed winning the scrambles championship on his B50 BSA and got second when
all he needed basically was to finish, but a broken chain sidelined him).

Perhaps consider getting a 14/39 spares, you can then try the 14/36 and
15/39 ratios as well.......

Peter


Date: Sat, 26 Aug 2006 15:26:23 -0700
From: "Jules" <jules at popmonkey.com>
Subject: [Ducati] wanted: 916 final drive ratio advice

the last time I was at thunderhill on my 916 I realized I never shifted into
6th and rarely into 5th (only on the straight) topping out at around 140
indicated.

so I'm thinking of switching from my standard 15/36 final drive to a 14/38.
is anyone out there running a bigger ratio and if so why?  is 14/38 too much
already?

~j