The gearing won't hurt you as much as other problems. You need to acquire
the tools and knowledge to take the clutches apart for adjustment and
cleaning.
As I mentioned in earlier post, the piston ported Kaw( results in weak
off-pipe HP) makes clutch tuning a little more critical.
If your CVT was tuned well for road racing, the secondary spring tension
with a torque button secondary was probably run fairly low around 8-12 # to
reduce overgripping the belt in order to help efficiency.
However, that low road racing secondary tension will probably work against
you in Solo.
With pipes that aren't at peak temp much, you will need more spring tension
to allow the upshift with less motor power. You will have good CVT
efficiency, but very low HP from the motor since it will not pull up on the
HP peak until the pipes are very hot.
Getting up into the 14-18 pound region is necessary with most Polaris
secondary setups. Use the lower end of that # range if a button type and
maybe even more than 18# if you have a roller secondary.
Measure tension with a fish scale clipped to the outer part of moveable
sheeve (no belt) Pull on a tangent-use the figure just after you barely get
it moving. BTW, a thin motorcycle tire iron is a pretty good tool for
getting a belt off.
The primary clutch engagement is essential to launching and both belt
clearance and spring/weight choice affect it. Shoot for 4500-5400 rpm
engagement
You can open up the belt clearance to maybe 45-50 thou before the clutch
will start slamming in too much coming out of corners and make it harder,
not easier to drive. 35 thou is a good starting point. Use a feeler gauge
between the belt and primary sheeves.
Increased primary spring pressure (not rate) will increase engagement point
RPM as well as less flyweight will. Use as much belt clearance as you can
stand first w/out "slamming", because doing it with lighter flyweight and
more spring reduces primary efficiency on the low end.
The combo of lower displacement (436cc vs 500cc) and inherently weak low end
from piston porting make this low range CVT tuning critical.
Expertise in CVT tuning alleviates a lot of the need for a lower final drive
like 4-5:1.
Leave it alone for awhile.
Lower final drive is a bandaid to some extent, but it does help CVT
efficiency to get out of the low range quicker.
A Polaris is inherently less efficient than a TRA in low range, but more
efficient than TRA as it shifts out, so the Polaris does benefit a little
more and TRA less from a lower final drive.
Chuck Voboril
From: john mensch <[EMAIL PROTECTED]>
Reply-To: [email protected]
To: [email protected]
Subject: [F500] Kawasaki cluch set-up....
Date: Mon, 4 Sep 2006 09:28:37 -0700 (PDT)
I'm having trouble with the seach engine on the 500.org site, so if this is
a well beaten horse....well accept my apologies.
I'm new to this f-440/Fmod business....
I picked up a Zink Z-19. It has been converted to a 4 link rear, I
hear I'm fortunate in that regard. Anyway, on to my question.
I had it out to a SOLO event last week, and the clutching seamed off.
It is geared for a road course (about 3.25:1), and it felt as though it
quite shifting at maybe 60-70 mph. Now there was some corrosion inside
the clutch (it hadn't been run in ? year), but a F-mod friend of mine was
helping and thought I had a pretty odd set-up.
Can anyone lend some clutch set-up info for a Kawasaki 440 with Polaris
primary & Secondaries?
Thanks,
John
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