LH Thomson introduced their dropper seatpost to great fanfare at Eurobike last year and have been hard at work making sure it meets expectations when it launches in April 2013.
I just visited their factory in Macon, GA, (separate post on that coming soon) and their PR man Dave Parrett spilled the beans on its progress and some upcoming variations.
While the recently introduced handlebars are coming from Taiwan, the dropper post is an even more international product. Parts are sourced from France, Malta, Taiwan and the US, among others. By the time it’s final assembly occurs in Taiwan, all external visible parts will be made in-house by Thomson, but internals are outsourced. Parrett says it’s essentially half of a suspension fork, and while they’ll eventually bring some more parts in house, probably not the suspension internals. That’s because their supplier had to ensure they last for two years minimum, and if Thomson started making some of the parts (valves, etc.) and something were to fail prematurely, the finger pointing would commence. Better to let the experts in their respective fields do their job.
Parrett says the cartridge is actually strong enough on its own to hold the rider, but for obvious reasons, it’s kept safely inside a sliding post. One such reason it to prevent rotation, and the original design we saw at Eurobike has changed a bit. They originally shaped the sliding faces into a dodecagon (12-sided polygon) to prevent saddle rotation. Parrett said it worked great, but after a few months of use, starting making a bit of noise. Now, they’re using a four-section keyed shape that, unfortunately, wasn’t on hand for visual inspection.
The internals are nitrogen charged and non-adjustable. But, the lever rotates a graduated cam, which depresses the release button gradually to give the rider fine control over the rate of drop and rise. The mechanism opens a valve, which moves oil from one side to another. When you release the lever, it cuts off flow between either side of the valve, and since oil won’t compress, it’ll stop at any point in its 5″ of travel and hold position. The nitrogen cartridge pushes it back up when it’s time to hammer. Nitrogen is used because there’s no moisture in it (versus air) so the internals won’t corrode, and it’s a bigger molecule so it’s less likely to leak.
Rotation and accidental drop are two of the most common problems associated with dropper posts, and Thomson’s taking large measures to ensure theirs won’t fail in either department.
“If you do what you’re supposed to do, it’ll last for years,” says Parrett. “But we have to figure out what riders are going to do that they aren’t supposed to. We’ve taken it through a car wash, driven in the rain at 80mph, tested it in -40°F to 140°F temps, and ridden it halfway compressed, among many others.
“That last one actually tore it up pretty good, which was a surprise. But something good to know before it got released.”
Right now, they’re on track for an April launch. One final change is that they’ll ship only with the remote cable actuated lever. Originally it was going to ship with that and the manual lever at the post, which could be swapped in with simple tools. But cost concerns and the fact that only about 10% of riders don’t use a remote meant it didn’t make sense to add cost for something most people aren’t going to use.
While we wait for that to hit shops, LH Thomson is already working on some pretty sick new versions and technologies…
STEALTH DROPPER POST
They’ll follow up the regular dropper post with a stealth version that’ll flip the internals and use a hydraulic nitrogen-over-oil mechanism to reverse the cable pull into a hydraulic push to actuate the post. Goal is a June 1 release date.
27.2 MOUNTAIN BIKE DROPPER POST
A 27.2 dropper post is also in the works, which will probably be limited to 3-4″ of travel versus the 5″ of travel for the larger diameters. ETA is Eurobike.
ROAD BIKE DROPPER+SUSPENSION POST
“We got beat to market pretty bad on the mountain bike dropper post,” Parrett said. “But our road one will be the first of its kind.”
It’ll have various drop capabilities that are tuned for different types of rough road riding, using similar internals as the 27.2 mountain dropper post but with unique features.
“When we make the 27.2 mountain bike post, it’s only going to be a dropper post. Our road one will have that capability, but it’ll also have a “Pavé” setting that’ll drop it about 5mm and add a bit of suspension to take the edge off rough roads. The amount of suspension travel isn’t determined yet, but the rider will be able to fine tune when the suspension starts working. The plan for now is to only have it move about 2-3mm through its travel, but that could change after testing. The goal is primarily to reduce vibrations and make the rider more comfortable, which should make them faster and last longer in the saddle.”
They’ll do this with a dual action lever. Push it down and it’ll drop through it’s travel, push it up and it’ll switch to Pavé…but this design, too, is subject to change. They’re pretty early in the development process on this but have stated Eurobike as a release date. We could see a post mounted lever being a good option here, keeping the bike’s aesthetics cleaner.
BLUETOOTH REMOTE CONTROL
From there, things get pie-in-the-sky, but Parrett says they’re actually working on a Bluetooth controlled circuit that can remotely actuate the post. One of the benefits is that it could potentially eliminate two SKUs (stealth and standard) for just one wireless remote version, eliminating the cable without sacrificing convenience…which is the ultimate goal. The immediate plan is to have a standalone Bluetooth switch that can be placed anywhere on the bike, but eventually they’ll have a smartphone app capable of controlling it.
By integrating the GPS, accelerometer and computing power of a rider’s smartphone, the app could automatically control the seatpost height based on incline/descent. Or, you could program it to learn a course and adjust the height based on location. No ETA on this, but they’re working on it.
NOTE: As I was finalizing this post, got word from Parrett that they just received the last of their test results and everything’s looking like production is set to start! We should have our hands on one before the April launch, so stay tuned for first impressions!