Not sure what size seatpost you have currently? There are a couple different ways to find out.• Most seatposts have the diameter printed somewhere near the bottom of the post. You'll need to remove the seatpost from the bike frame (mark your existing seatpost height with a bit of tape before you remove it so you can replace it easily), and look for a number like 27.2, 30.9, or 31.6 (etc.). That is the diameter of the post. Same idea as the Girvin Flexstem that I fitted to my mountain bike nearly 30 years ago and which was very effective in those pre suspension fork days. Nothing new under the sun. Fit: The stem only comes in a 6-degree angle and a few lengths which can be very limiting to some riders. In general, you'll find the +30 deg stem provides a more upright, comfort-oriented fit, whereas the +/-6 deg stem puts you in a more performance-oriented riding position (standard for a typical road bike).

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The five supplied elastomers are coloured and marked 50, 60, 70, 80 and 90 in relation to their durometer values. Improved handling: The suspension system of the stem can help to improve handling and stability, particularly on rough terrain or when riding over bumps and potholes. an average of the other scores: it reflects both a product's function and value – with value determined by how a product Elastomers (2 pre-installed, 3 additional) to customise the ride feel for your bike, weight, and riding style

During much of the test period I was riding 50mm carbon aero wheels with 25mm tubeless tyres – a rather radical departure from my usual 24mm alloy rims and 28mm tubeless. How does it feel?

Sadly I couldn't work out what the effect would be if tyres and pressures were already wider and lower. On my Al road bike, which is pretty buzzy (hence my burgeoning obsession with this) I'm on 28 mm and 70 ish psi. Any lower and a feeling of vagueness like Matt Lucas impersonating Boris Johnson comes in as the speed gets above 35 km/h (descending only, I seldom get a tailwind for that speed on the flat). The bottom of range Michelins might be a factor. So this might help a bit. is our standard size, but we added the 280, 400, 450mm to allow for a wider range of fits. Measure your current seatpost from the clamp collar to the saddle rail: Once you determine the length of your existing stem round to the nearest 10 mm and choose the closest match. Warming to a theme here (& it's a bit warmer than the weather), I found an academic paper (pdf) comparing a Redshift, a TranzX and a standard aluminium stem here: https://www.google.com/url?sa=t&source=web&rct=j&url=https://www.mdpi.co... Redshift suggests that riders up to 80kg should only use the main spring and those from 90kg to 110kg must install the inner spring as well. With the main spring fitted, my unit weighed 538g.

I preferred to go softer on the elastomers than suggested (10 on one bike and 20 on the other) but as said there's no sense of compression with normal riding and no diving under braking but going down hill above 30mph and the stem absorbs the impacts with little change on handling feel. Take control - customize your suspension feel to float over obstacles and maintain control over rough terrain Details:BMC claims the torsional stiffness is equal to a standard stem and that you’ll only feel the effects of the suspension when it comes to smoothing out rougher surfaces. The stem comes with five elastomer rigidities that can be mixed and matched to fine-tune the feel. In total, there’s up to 20mm of tunable suspension. Alternate method: Use a fabric or paper measuring tape (or print one at https://printable-ruler.net/ ) and measure the circumference of the handlebar right next to your existing stem. Alternate method: Use a fabric or paper measuring tape (or print one at https://printable-ruler.net/ ) and measure the circumference of the steerer tube. You will need to remove the compression cap and loosen the two pinch bolts to get access to your steerer tube so be sure you are comfortable in doing so and then reassembling properly. Should you put a front suspension and a Redshift stem at the same level when it comes to smoothing out trail buzz?

It's for people wanting more comfort/less hand and arm vibration from the roads, without going to wider tyres. It can feel a little weird at first until you get used to the movement, but it soon becomes normal, and with the firmer spring rate there is minimal 'bob' when riding on smooth tarmac or when you are out of the saddle. The Bike Computer Mount is an integrated mount that is compatible with your Garmin, Powertap/CycleOps Joule, CatEye, Mio, or Magellan computer. I was an early adopter of the stem and am a convert. I have one on my CX training bike and it provides just the right amount of comfort suspension. To me, it feels like the amount of “suspension” a perfectly inflated tire gives you. I’ve ridden mine where ever my bike takes me, from the road to riding my CX bike on mountain bike trails in the area.JamesWalker - I too have one on a Orro Terra C, it has did me proud on the Dirty Reiver and Yorkshire True Grit. Five durometers of elastomer insert enable you to tune the suspension to your own preference. Jérémie Reuiller BMC