Although the concept certainly isn’t a new invention
, dropper seatposts may be the most important innovation to emerge from the new century. I am a dropper post fan for sure, but there are a lot of times when I am Enduro-style riding and only use the dropper once or twice, which makes the weight and complication (and the $150 to $350 cost) of a telescopic seatpost seem redundant. Often, the best descending option for aggressive trail riding is a half-way position, with the saddle’s height reduced just low enough to get the center of gravity down, but still high enough to facilitate an occasional pedaling section. It was one of those rides that got me wondering, ‘Could there be a Ghetto solution to the dropper post that weighs next to nothing, costs less than 20 bucks and could be made at home?’ Well, it turns out that there is – sort of.
Welcome to another edition of Ghetto-Tech Tuesday, where we will learn to craft a few parts and make modifications to household items that will enable us to quickly and accurately drop the saddle and then return it to a specific ride height. Before you get all excited, though, the end product of this experiment will not perform anywhere close to a RockShox Reverb or a KS Lev seatpost, but it will allow you to get the job done on the fly and reasonably quickly. If you are living on the cheap, or don’t want to commit to an expensive dropper post, this Tech Tuesday is for you.
Ghetto Level One: Make a Seatpost Travel Limiter
I met a guy named Harold a few years back who crafted a limiter ring from an unused plastic reflector bracket. He clamped the ring half-way up his seatpost so he could unclamp the frame’s quick release while he was riding and lower the post to exactly the same spot every time. I made one the next day and it is quite useful – and free, providing you can scrounge up a bracket at your local bike shop.
Tip: Rear reflector kits usually mount to seat posts. Many front reflector clamps, however, are designed for handlebars – and those smaller-diameter clamps can often be used to make limiters for telescopic dropper posts.What You’ll Need:
• The correct diameter reflector clamp.
• Sandpaper or a medium-tooth file.
• A fine-tooth hack saw or similar cutting device.
• Phillips screwdriver.
• Vice or suitable clamping device.
• Sharpie marking pen or similar.
Step One -Locate a reflector assembly with a clamp that will fit your seat post. Best practice is to bring your post to your LBS on a slow Wednesday and ask them to poke around for one. Discard the reflector assembly and then snug down the clamp screw to firm up the band.
Step Two -Clamp the band in a vice or similar and cut off the excess plastic material from the clamp with a fine-tooth hack-saw blade. Use a file or abrasive paper to smooth the clamp profile.
Step Three -Remove the seatpost, clean any residual grease or oil from the post and then slide the clamp onto the post. Replace the post into the frame and then set your saddle height to its cross-country position. Raise the clamp to approximate how low you want your saddle to drop and clamp it snugly in place. (I set it about 2.5 to 3 inches for starters). Tighten the clamp screw and you are ready to ride.
Tip: before you set out, drop the saddle and put your weight on the collar to check that it is tight enough to stay put.
Ghetto Level Two: Complete Your Dropper Post With an Up-Leash
Clamping a ring part way up your seatpost allows you to quickly and accurately drop the post on the fly using the quick release lever – but you will probably have to dismount at the bottom of the descent to return your saddle to its proper ride height. Armed only with off-the-shelf bits that you probably have laying in the back of a drawer, you can fashion an upward travel limiter that will ensure your seatpost will return to the same height every time. Of course, you still must move the post by hand, but you won’t be moving it more than once – and with practice, you will be able to return your saddle to ride height while you are rolling. Watch and learn.What You’ll Need:
• A derailleur cable.
• 3/16-inch copper tubing or two 12 / 10 gauge wire terminals.
• 8 inches of plastic cable-liner tubing.
• Cable cutter.
• Wire crimping pliers or similar.
• 3 inches of ¼ inch shrink tubing.
• Heat source (a butane cigarette lighter will do).
• Fine-tooth hack saw.
• Abrasive paper.
• Measuring tape or ruler.
• Sharpie marking pen or similar.
• A previously installed Ghetto travel-limiter clamp.
Step One -Ensure that your saddle height is set in its correct upper position and the seatpost clamp is secured. Mark the position of the limiter collar.
Step Two -Using the fine-tooth-blade hack saw, cut two lengths of copper tubing about 3/8 inch long (10mm) and sand the edges smooth. Now, cut two 5/8 inch (16mm) pieces of shrink tube. Set them aside.
Step Three -Observe and make notes. You will be using the derailleur cable to fashion a leash that loops around the top tube where it intersects the seat tube. If your frame's top tube has a forked reinforcement like Specialized and Cannondale, your leash will run forward of the seat tube. If your frame is conventional, single tube design, the leash will run behind the seat tube.
Step Four -Make a trial loop leaving enough slack to allow the leash to slide comfortably back and forth on the frame tube. Your wires will need to overlap three inches or more so there is some working room. Mark where the wires cross to form the loop with the Sharpie. Using your marks, cut a length of plastic cable liner about 1/4 inch shorter than the length around the loop.
Step Five -Slide one piece of shrink-tube, one piece of copper tube and then slide the plastic liner onto the cable. Next, loop the assembled cable around the seat tube and then slip the loose end of the derailleur cable back through the copper tube to make a loop. Pull the cable through until both Sharpie marks line up with the end of the copper tube. Crimp the copper tube with the wire terminal crimp pliers towards one end then check to see that the loop does not bind or catch on the frame tube. Good? Crimp the copper tube a second time on the opposite end and you should have a sweet looking loop.
Step Six -Loosen the seatpost limiting collar enough so that the derailleur cable can be slipped under the clamp and then turn the clamping end so that it lines up with the cable leash assembly.
Step Seven -Slide the cable under the clamp where the gap is and then thread it back through the copper tube. Tighten the collar just enough to keep it in position, while allowing you to pull the derailleur cable through the gap. Pull the cable tight and then slide the copper tube up the cable until it sits about 5/8 inches (16mm) away from the collar. Mark the wire at the top of the copper tube.
Step Eight -Slide the seatpost down an inch or so to give you some room to crimp the copper tube. Slide the copper tube until it lines up with your Sharpie marks and then crimp it in two places.
Step Nine -Grab your cable cutters and trim the derailleur cable as close to the ends of the crimps as possible. Slide the shrink tubing over the crimp, making sure that it overlaps the cable ends and then use the cigarette lighter or a similar heat source to shrink it in place.
Step Ten -Your Ghetto dropper post should look something like this. Check that your seatpost limiting collar is tight and then give your bike a ride to ensure your saddle height is correct at full extension. If it needs an adjustment, loosen the limiting collar and add or subtract the distance you need to get it right. Most riders who manipulate their quick-release seatpost clamps on the fly, run the lever facing forward because it is more natural to twist the wrist that direction when in the saddle.
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