Crankset Sizing and Bottom Brackets
Are you looking to upgrade your drivetrain but unsure of what specs you need to suit your style of riding? Mountain bike specs are often only millimeters different in size, yet those tiny differences in specs can make a huge impact on your riding. Cranksets are a perfect example of this. The standard size of cranksets usually ranges between 165mm, 170mm and 175mm. Minimal difference, right?
That 5mm difference is actually huge in the world of mountain biking. That 5mm could be the difference of you clipping a rock or root and flying over the handlebars. Having a shorter crankset definitely gives you more clearance on the trail but it also takes away from your pedalling efficiency. Typically a downhill rider doesn't need to pedal as much so having the extra clearance of a 165mm crankset can be a big help on the trails. Those who enjoy cross country and want to maximize their pedal strokes get more advantage from the longer 175mm crankset. Then of course there are those who are right in the middle, wanting a bit of clearance but also don't want to sacrifice all of their pedal strokes who fit in the 170mm category.
The next big question is- "What size of bottom bracket do I need then?" There are two main sizes for bottom brackets, 68/73mm and 83mm. If you are riding a 170mm or 175mm crankset, you are best suited for a 68/73mm bottom bracket. Those who ride a 165mm crankset benefit more from riding a 83mm bottom bracket. Since generally a DH rider is riding rougher terrain, it is more important to have a wider and therefore stronger bottom bracket in place.
For all of your crankset and bottom bracket needs, spend less and ride the best with TBS Bike Parts! Most cranksets available at TBS Bike Parts include bottom brackets unless specified otherwise.