Fox Release New Transfer SL
Fox release a new and shorter travel version of their Transfer post - the Transfer SL
. Although it might share some visual similarities to its bigger sibling, it's a new post from the ground up which comes in 25% (128g) lighter than the standard Transfer.
Fox's goal was to make the lightest dropper post on the market for XC applications. The post starts at 327g
for a 27.2mm Factory Series model. There will be lever options for drop bars as well as flat and double shifters. The 1x lever is Matchmaker, Shimano GRX, and I-SPEC EV compatible. The Transfer SL will only be available with internal routing.Different Priorities Sees a Different Seatclamp
One of the biggest indicators that this isn't the regular Transfer post is the saddle clamps. If anything, it looks more like a previous generation of the Transfer. Why have they done this? Simply put, weight.
The standard Transfer’s saddle clamps are made to maximize travel for the post length that is exposed outside of the frame. However, the SL isn't held to the same design constraints. In XC applications exposed post length is not such a limiting factor therefore minimizing post length doesn't reap the same benefits. The design freedom allowed by this enables the Transfer SL's clamp to prioritise low-weight over a low-stack height setup.All-New Mechanical Spring
The Transfer SL offers a two-position system, as opposed to the infinite adjustment you may well expect. Fox say they do this for two reasons: weight and need. Typically in XC racing the post is almost always completely up or down and riders tend not to ride with it set to halfway. Because of this Fox claim there is no benefit to intermediate positions.
Another place where Fox may subvert your expectations is by using a mechanical spring. Although it might seem slightly counterintuitive, this is again done to reduce weight. Air is of course lighter than metal. However, the associated weight needed for adequate sealing to make an air spring airtight is where the grams mount up. Using a mechanical spring eliminates the need to create a sealed air chamber. It also foregoes the oil required in a hydraulic system. Again, this is another weight saving benefit to the mechanical spring.
Because the Transfer SL's spring is only used to extend the post and not support rider weight the required spring rate is very low. This means the spring can be lighter still. Fox say the SL post's have empty space where oil would exist in a hydraulic post.
Sizes and Pricing
The mechanism Fox use will also have a slight noise to it, and this is completely normal. This is because the locking mechanism has hardened steel balls that engage in internal grooves in the upper post to lock into one of two travel positions.
The Transfer SL uses an anti-rotation mechanism to keep the upper post from rotating in the lower post, which has a distinctly different feeling to other posts. The mechanism has two preloaded bushings so there is zero angular ‘free play’ at the saddle. Instead, there is a spring-loaded feel if the saddle is twisted. Most dropper posts use rigid parts (the regular Transfer uses brass pins) to prevent angular rotation of the upper post, which results in a small amount of angular free play until the rigid parts engage. It's worth nothing however that the 27.2 diameter post uses traditional anti-rotation pins so there is some saddle angular free play with hard rotational stops.
A highly preloaded low rate spring, combined with no speed decrease because of the lack of hydraulic oil flowing, means the post should compress easily but still return quickly. Fox say that the return speed of the SL is slightly faster than Transfer.
• 27.2 x 50mm
, 80mm min / 248mm max insertion, 350mm length, Starting Weight: 327g
• 27.2 x 70mm
, 80mm min / 248mm max insertion, 370mm length, Starting Weight: 338g
• 30.9/31.6 x 75mm
, 80mm min / 225mm max insertion, 355mm length, Starting Weight: 342g/352g
• 30.9/31.6 x 100mm
, 80mm min / 225mm max insertion, 380mm length, Starting Weight: 347g/359g
• XL 31.6 x 100mm
, 80mm min / 275mm max insertion, 430mm length, Starting Weight: 399g
Essentially, in a 27.2mm
diameter, there will be 50 and 70mm options. There will then be 75 and 100mm options available in 30.9
versions. There will be the Kashima Factory model, which also benefits from lighter titanium hardware, and the blacked-out Performance Elite model.
Fox will also make an XL version of the Transfer SL. This is because some bike and rider combinations will not be able to achieve correct saddle height with the ‘normal’ length post. For such riders, the XL exists. Most users will be happy with the standard length, but it's good to see Fox catering to people of different statures. The exposed length of the XL is 50mm longer and it's only available in a 31.6mm diameter.
The RRP for the post is $399 USD
for Factory models and $329 USD
for the Performance Elite line. Please visit their website
for more information.