'99- should I worry about the crank?
randygrein at comcast.net
Sun Nov 16 11:19:22 PST 2008
I've not heard of specific problems with the 1st gen bike that were
not attributable to extreme wear, rider mismanagement or lack of oil.
The early crank rumors appear to have been caused by poor downshift
management. There are a few things you can do:
First, listen to Zoran.
Second, remember that we ran a stock engined 1st gen bike at the 24
hours of Willow - and took 13th place out of 23. Zero problems aside
from Z running out of gas at 1hr 19min. (grin)
Third, there are a couple of things you can do to increase
reliability. Overreving has been implicated in some engine failures -
specifically banging multiple downshifts at the end of a straight and
NOT watching engine RPM. Recognizing the ideal shift points helps.
Unlike some modern multi cylinder bikes peak power for the stock bike
is around 9200 rpm with a considerable dropoff by redline. Of course
it depends on how the bike is altered - I've had bikes that followed
this pattern, and I've had bikes with absolutely flat power curves
from below 8,000 to 10 grand; paying for a couple of dyno runs to see
yours is well worth the money. If it's flat it doesn't matter where
you shift so long as you stay within that plateau, if it drops off
you're better off short shifting. Either way you'll KNOW what the
right shift point is. If there's no power advantage to wringing it's
neck, why do it?
Finally, the second gen crank can flex some at high rpms, which oddly
can walk the main bearings in to the center, cutting into the crank
and causing failure. These bearings are pressed in, and the press fit
does not always have sufficient hold. Zlock racing identified the
problem and has engineered a solution. The 2nd gen rods are also weak,
at least some years. Standard fix is to replace with 1st gen rods.
The second gen bike is definitely better. A bit more power stock, no
jetting to mess with. Just wished they would upgrade the suspension.
Randy Grein, WMRRA #41
On Nov 16, 2008, at 10:35 AM, Aaron Turner wrote:
> I'm hoping to start racing AFM in 650P next year and there's a
> race-ready '99 for sale on BARF (I'm sure most of you know the one I'm
> talking about).
> Anyways, other then paying two mortgages (anyone want to buy a
> townhome in SJ? :), the one thing I'm worried about is what I've heard
> about the early SV cranks not being up to snuff for racing/trackdays.
> Anyone care to comment on how real this issue is? Are there solutions
> other then being a pansy on the throttle? Or should I just wait for a
> prepped G2?
> Aaron Turner
> http://tcpreplay.synfin.net/ - Pcap editing and replay tools for
> Unix & Windows
> They that can give up essential liberty to obtain a little temporary
> safety deserve neither liberty nor safety. -- Benjamin Franklin
More information about the SV650