- Customer: Greg Wurster
- His Ride: '81 CB900F
- Customer Since: 2018
Hello,
This is my single family, 2 owner 1981 CB900F original AMA Pro 1025 SuperBike class race bike. I say original because all modifications, with the exception of porting and break component replacements were done in 1981/82 by my father who bought, modified, and raced in the Rocky Mountain Amateur AMA league at that time. He also ran around with AMA Pro Dr. David Kieffer in the pits. I'm told Kieffer is who introduced Dad to Dennis Zickrick.
Starting up front the chassis modifications are:
Fork dampening rods ported.
Fork springs: progressive for 165lb rider.
Focci(sp?) Break disks and pads - recently replaced with EBC rotors & H-H pads.
Brembo Stainless break lines.
BMW RS40 bars
Altered rake & trail
Altered petcock & lined tank
Strengthened frame & engine mounts
Sport Kit rear sets
Bol D'or stylized strengthened swing arm
Racing Werks rear shocks
Engine & Drive mods:
Bored 3rd over to 1010cc, not sure about stroke
Cammed
Valved
Ported (done mid '90's)
Weisco high compression pistons 13:1
Blue printed & balanced
Barnett heavy clutch pack
Zickrick Shaved & beveled transmission gearing
Mikuni VM33 smoothbore 4 pack with K&N individual pod filters
Mikuni push/pull throttle
Dyna 2000 coils
Yoshimura 4-1 custom exhaust with individual cylinder tube O2 ports for dyno tuning.
18/44 final drive 530 chain; 15, 16, & 17 front and 42, 43, & 45 rear also on hand. Note: front sprocket cover does not fit with the 18t sprocket installed.
Engine work done by HRC Engine mechanic, Dennis Zickrick, yes, THAT Dennis Zickrick, again, back in 1981/2.
Dyno spec at 3,360(ish) feet altitude in third gear on a tire/drum style dynamometer:
96.6rwhp, 102.2lbft @ 9,000 RPM
We (I & the dyno tech) set 9,000 as a safety margin, not knowing where safe/unsafe was. Come to find out later, under full racing conditions red line is actually around 11,000 according to Mr. Zickrick.
My dad transferred the title to me in 2011 when he finally realized his dream of owning a Ducati. Mom put the foot down and said only one bike at a time... I wasn't about to let this un-wrecked original era racer leave the family, & Dad agreed. Cost was transporting his new Duc from Eraldo Ferrucci's shop (Thank-you, Keiffer, R.I.P.) back home to Montana.
Thanks,
Greg W.