BARE BONES: THE INS & OUTS OF SHORTENING YOUR SUSPENSION BY BONES BACON
From time to time I am asked to shorten suspension for people. Mostly it’s due to the rider’s legs not being long enough to reach the ground. But, it is more common to do this for offroad riders than it is for motocrossers. I also get requests for shorter suspension for riders doing Supermoto or dirt track racing.
Whatever the need may be, shortening suspension is popular; however, there are ways to get your bike lower to the ground other than doing it mechanically within your suspension components.
First, you can work with the chassis. For example, depending on what kind of bike you have, you may be able to slide your forks up through the triple clamps to lower the front end and then install a longer link arm to lower the rear. This will lower your bike as much as 10mm at both the front and rear, but will also firm up the linkage curve initially.
Second, you can look into getting a lower seat or running a cut-down seat. Don’t laugh. Many factory riders have seats that have been trimmed to the bare minimum. Keep in mind that if you go this route, you will be sitting down into the bike, which is what you want, but you might have to run lower bar mounts or lower bars to balance everything out.
Third, you can have the subframe lowered. This requires some welding and a modicum of math skills. Moving the lower subframe mounting holes up 5mm will lower the rear fender as much as 15mm. This is also very common on factory bikes.
“I’VE SEEN MANY SHORT RIDERS LOOSEN THEIR SHOCK SPRING UNTIL THERE IS NO PRELOAD ON THE SPRING SO THEY CAN TOUCH THE GROUND.
THIS IS A BAD IDEA.”
If none of these suggestions are your cup of tea and you want your suspension components shortened, keep in mind that if you are using your bike for motocross, you don’t want to get too carried away. The shorter you make your suspension, the shorter the shock’s stroke, which translates into less wheel travel. Luckily, most modern bikes have plenty of suspension travel that they can afford to lose a little without any major performance loss. And, actually, in some Supercross applications, a little less stroke can be a good thing. But, for most racing applications, I would start with chassis changes first and then look into getting your suspension components shortened if you’re still not satisfied.
For play riders and trail riders, suspension travel isn’t such a big deal, and the ability to touch the ground with your feet in difficult sections of trail may be worth the trade-off. Additionally, shorter suspension will lower the center of gravity of your bike. A lower center of gravity can make the bike more maneuverable and easier to turn down tight, twisty trails. It goes without saying that Supermoto and dirt track racers need to have the center of gravity as low as they can get it, as they don’t really need a lot of suspension travel.
I’ve seen many short riders loosen their shock spring until there is no preload on the spring so they can touch the ground. This is a bad idea, as your sag will be way too much, shock performance will suffer and your bike’s head angle will be kicked out so far that the bike won’t want to turn. Balance between the front and rear of a bike is very important. If you lower one end, you must lower the other—this way the bike will continue to handle properly.
handlingDifferent bikes may require different methods of shortening the suspension. Most shocks can be lowered with a few simple methods. A different stop plate can be machined. A simple spacer can be installed between the stop plate and seal-head bumper, or even some plastic washers can be installed in the same spot. Obviously, care has to be taken so you don’t block off the shock shaft’s bleed hole, but for the most part every suspension shop can handle the job with ease. Be forewarned that a shorter shock spring may be required, depending on how short you are going.
Forks are more complicated to shorten, as there are many different styles of sealed cartridge forks. When adding a travel-limiting spacer in your forks, you will end up with much more fork spring preload. At this point you can’t just reduce the preload like you can on your shock spring. Depending on the fork, you may need to machine a new spring perch circlip groove, alter the spring spacer or run a shorter spring.
If shortening your suspension is something that you think will help you and your bike become a perfect fit, it can be done. And, although I’m 5-foot-17-inches and don’t have this problem on my bike, I sympathize with riders whose feet don’t touch the ground.