Want a “faster” bike without spending a ton of money? Hands down, the easiest and most cost-efficient way to a quicker accelerating motorcycle is to adjust your final drive gearing. By adding a smaller front sprocket or a larger rear sprocket to your bike’s final drive ratio, you can essentially “tune” the bike’s power band to be more accessible at lower RPM levels. Sure, you’re giving up some top speed, but how often do you really hit the rev limiter in top gear?
Take, for example, our test mule: the mighty Kawasaki ZX-14R. With a top speed easily north of 180mph, it’s safe to say riders of this beast can’t legally access its upper limits on any public road in the good ol’ U.S. of A. So why not add a little more grunt to the biggest Ninja’s already prodigious bottom end? Why not, indeed.
For this How-To installment, we’ll be dropping a one-tooth smaller JT front sprocket onto the 14′s final drive. To get started, we’ll remove the lower fairing to gain access to the sprocket cover and other bits packed around it. Next up, we’ll move to the side the clutch slave cylinder (careful moving this to avoid any kinks in your cables), the Nina’s speed sensor and the primary sprocket cover.
Once the workspace is opened up, mounting the new sprocket was a simple affair. First, you’ll remove the sprocket nut and lock washer (be sure to get a have a new replacement washer ready for remounting, as these washers need to be bent upon mounting). Once the nut and washer up are removed, loosen the rear axle nut so you can move wheel forward, loosening the chain enough to move it off of the sprockets. With the chain tension removed, simply remove the chain fully from the front sprocket and ease the sprocket off of its shaft.
Installation of the new sprocket is equally simple. Just follow everything up this point in reverse. Mount up the new sprocket on the drive shaft (make sure to mount the sprocket numbers-side out), remount your chain to both front and rear sprockets, then get some tension back on the chain by backing out the rear wheel chain blocks. Before tightening the rear axle nut back down, be sure to line up the swingarm wheel marks to ensure proper rear wheel alignment. Tighten up both front and rear sprockets to spec, and bend the front locking washer to hold the sprocket in place. Finish things up by remounting the sprocket cover, speed sensor, clutch slave cylinder and lower fairing. All done!
Once mounted, we were curious about the Ninja’s newly altered power curve. TO see how much effect the smaller front sprocket had made, we headed down to the CCPowerSports Louisville location for a quick spin on the dyno. Much to the delight of our power-addled brains, we found a jump of 5-15 usable horsepower between 40-100mph. The trade-off? A loss of around 10mph on the top end. A fair trade, we thinks.
Wanna try new gearing for your bike or race quad? Check out CheapCycleParts.com for a full selection of sprockets, chains and more.