“Building a SBK Factory ZRX has been an awesome experience, even though I tried to build one in a VERY short period of time, less than 2 months! Without James Compton being so generous with his time and knowledge there’s absolutely no way I could’ve gotten it to this 90%-complete state for a track ride before theMinnesota winter sets in. All the parts and fabrication James provided has been top-notch, and at a very fair price for the level of quality you are getting.
The end result is an incredible track bike that has surpassed my expectations in the way it performs; it actually works better than it looks, if that’s even possible. It is a completely legit track weapon that doesn’t have any handling quirks or deficiencies that I could find, and I’ve ridden mine pretty hard over two days on two very different tracks. Obviously SBK Factory’s Pike’s Peak performance (2nd & 3rd in class / 3rd and 6th overall) leaves little doubt as to what these bikes can do. And it must be said all this performance is very accessible. Probably the easiest roadrace bike to ride fast that I’ve thrown a leg over. Direction changes, turn-in, trail braking, stability (without a steering damper) immense rear grip when you put the power down… this thing really boggles the mind with how capable it is.
With all of this performance I’m also completely enamored with the character of this thing; the rattle of the flat slides at idle, the wail of the exhaust, just sitting back and looking at it… Like James’ said “These things are like a ’69 Camaro, they’ll always be cool.”. And he’s spot-on with that assessment, but I’ll take it a step further; these bikes will run with their modern counterparts in a way an old muscle car never could! A perfect blend of modern and retro in my eyes.
Some details: I went with all the suspension mods James reccomended: Late-model R6 forks with GP Suspension internals built to his spec. Penske 8983 shocks, again built to James’ specifications. Chassis numbers are all to James’ spec except for the triple clamp offset being stock-R6 30mm compared to James’ 28mm using his full triple clamp assembly. I currently have an aftermarket top clamp (hence the 30mm offset) which will allow a superbike bar, but after riding with the upside-down and reversed clip-on setup James recommends, I realize this seating position is right on the money and comfortable enough should I put lights on this thing. SBK top clamp incoming!
For fueling I followed James’ recommendation for FCR39 flat slides, these absolutely transform the engine’s character and turn what is a dip-filled, underwhelming power band into a huge wave of power that starts from the very bottom and pulls hard all the way to redline without a single dip that I could feel. Not bad for a stock, 50k-mile motor! Throttle response is also better than any fuel-injection system I’ve ever felt. This thing urges you to get on the power hard and early. Exhaust is James’ combination of Muzzy and custom pieces, the sound is amazing.
SBK Factory’s gorgeous carbon tail section and number plate slim down the bike’s profile tremendously. Using this tail piece requires cutting a sizable piece off the subframe and welding in a support-hoop sold by SBK Factory. Figuring this part out wasn’t actually as tricky as I thought, of course a competent welder/fabricator is required to tie everything together. I’d highly recommend going with both the billet battery box and countershaft cover/clutch slave support. Both allow you to remove several unsightly and/or heavy parts, the battery box in particular will save you from having figure out your own solution, plus it’s trick!
How much did all of this cost to get the bike to this point? Well, I was almost afraid to start adding up everything I’ve spent since first picking up the bike a couple months back. Let’s just say I exceeded $10k not including the cost of the $2,600 stock ZRX. No small amount to be sure, but as you can see above, I didn’t skimp on the big items: suspension, triple clamps, fueling, brakes (Brembo and SBK Factory), master cylinders, bodywork, magnesium wheels and plenty of little expenses here and there definitely add up. Is it an expensive build? For me yes, yes it is. Is it expensive compared to building a modern liter bike for track use, or buying something like a Panigale S for the track? Well now it’s starting to look like a bit of a bargain… and I wouldn’t trade this thing for one of those bikes anyway. The SBK Factory ZRX is that cool and performs beyond expectations. Easily the coolest bike I’ve ever owned.
SBK Factory, you have my gratitude.” -Nick J. from Minnesota