Cycle News is a weekly magazine that covers all aspects of motorcycling including Supercross, Motocross and MotoGP as well as new motorcycles
Issue link: https://magazine.cyclenews.com/i/128382
do you a damn bit of good if you don't know how to set it up properly. Related to that is the experience of interpreting the rules and choosing the best components and modifications to get the most out of the bike. This leads to another thing: the manpower to first build and then keep these bikes running perfectly and performing at their peak level all the time. Everything else you can buy, because these bikes are just big Supersport bikes. Experience is one thing that the Graves Yamaha team has a lot of. From its humble beginnings, the team developed an alliance with Yamaha that has grown for the past eight years. So what can you do to a Superstock machine to make it race-ready? Here is the basic rundown on the modifications that are legal for AMA Superstock competition. All of the street equipment, including the lights, signals and any other DOT-required street equipment, can be tossed. The bodywork is obviously changed to lighter aftermarket stuff; Graves uses Sharkskinz. The hand and foot controls can be changed to suit the rider's preferences - in this case, Graves rear-sets and a combination of CRG (Constructors Racing Group) and Yamaha levers. The braking system can be upgraded with the use of aftermarket brake lines and pads (Ferodo on these bikes). Graves also attaches an Ohlins steering damper to keep the beast from throwing you off, though I'll come back to that in a bit. The suspension is one area where the team's experience is critical. The front fork is a stock 43mm inverted KYB RI unit with an Ohlins "factory" spring kit inside; the rules do not allow the fork to be swapped. Out back there is a little more freedom, and an Ohlins rear shock with a hydraulic preload adjuster and piggyback reservoir slots into place. This shock also allows the team to change ride height to get more weight up over the front of the bike and to improve the steering. No modifications can be made to the frame. The Graves Superstock RIs run on Dunlop slicks mounted on stock rims as per the rules. As for the motor, there are very few modifications that can be made, not that the Yamaha needs much help in the first place. No porting or polishing is allowed to improve airflow into the cylinder head, but the compression ratio can be altered by milling the head, block or cases. The camshafts must be stock, but slotted cam sprockets may be added to fine-tune the cam timing. The stock crank, rods and pistons must be used. The ECU may be replaced with a unit such as the programmable Dynojet unit that Graves uses, which allows it to adjust the injection and ignition mapping. The RIs run Graves' own full-titanium exhaust system with titanium canisters. The bikes are set up to run on VP Racing fuel. The rules allow the use of an ignition-kill speed-shifter, which allows wide-o en upshifts. The clutch springs arid plates may also be upgraded, as can the final drive sprockets and chain; the team uses AFAM sprockets and D.I.D. chain. I rode Ha king's bike first and immediately noticed that the suspension was a little soft for me in terms of preload settings, but the damping was really nice, so it wasn't a big deal. At first, I planned on just cruising around and getting a feel for the bike, but I got comfortable on the bike fairly qUickly. I did have two good scares on Hacking's bike early in the session. Exiting Willow's fast turn nine, I rolled on the throttle and spun the rear Dunlop slick up a bit, which I didn't think was a big deal. However, I chopped the throttle a little too abruptly and was still leaned over, which sent the bike into a serious tank-slapper. I was trying to get the bike completely vertical and at the same time trying to stop the shaking. I probably shouldn't have gotten out of the throttle in the first place, so I tried going full throttle again, and the headshake got really bad - like trying to rip the handlebars out of the hands bad. Finally, I picked the bike up vertical, shut the throttle off and and I never really felt like I was pushing it. As a matter of fact, I was riding carefully in order to bring it home in one piece. I could have sliced a second to a second-and-a-half off easily just by riding a little harder through the track's tight stuff (sure, Blake, sure... Editor). However, at the time it didn't seem prudent to highside the bike to the moon while others were waiting for a chance to ride it. When you break it all down, there are really only a couple of things that separate these bikes from the average privateer bike. The problem is that those are items that can't really be purchased from Graves Motorsports and bolted onto the bike. The most important is a very experienced team. After all, an $1 IOO-plus Ohlins shock won't CYCLE NEWS • JUNE 15,2005 47