Thomson X4 31.8 Bicycle Stem

Great product! Thomson always delivers.

The Thomson X4 stem is awesome. Its one of the most chiseled and purposefully built components in my opinion. It is one of my first 21st century bike products. I got it for my DF3 and it fits the whole look of the bike nicely. Its nice and beefy and cleanly machined unlike most of the other stems that look all soft and doe like. All the bolts screw in smoothly and it holds my 3T Scatto bars tight with no carbon sandy grease during my standing start efforts. I got it for my new Dolan DF3 frame so I had to try different stem angles and lengths until I got the right fit. I went through 3 stems before finding the right size and they were all Thomson X4s because I was so impressed by their build quality and clean edged look and I'm an industrial designer with impeccable taste.

I am using the X4 on a road bike although it's marketed as a mountain bike item. As such, there is about a 50 gram weight penalty over say a Ritchey or a 3T road stem. Thomson's X2, the road-specific stem, competes in weight but I can't recommend it due to flex and the clamp having only two bolts. Headscratcher there...the X2 is Thomson's only mediocre product. The X4 benefit however is vastly superior stiffness - noticeable immediately and, the large clamp in my logic will be inherently kinder to finicky carbon handlebars. A stem review by Fairwheel Bikes a few years ago actually measured "compliance" i.e., flex under a twist load as in riding. Out of a bunch of carbon and alloy stems, the Thomson X4 took second overall being bested only slightly the Shimano Pro Vibe sprint version seen on Cavendish's rig and Theo Bos's Keirin bikes. The Thomsons are the best made stems and seat posts available in my opinion. The machining is exquisite and the overall quality is without equal. I can also validate Thomson's claim as to their seat post clamp being superior. That thing is the best way to NOT crack your $160 carbon post as it holds securely at 2.8 Nm. (BTW, get yourself a REAL torque wrench - not the "clicker." I learned that after cracking two of them...ouch.)

Was looking for a shorter stem for my Cannondale Jekyll with 1.5 inch steerer tube. This is hard to find as most bikes are 1.25 inch. This fit perfectly and really changed the feel of my bike. I feel more stable on decents and steering is more responsive than with the stock stem. A shorter stem is a great way, relatively inexpensive way to change the ride characteristics of your bike. It also looks a lot better now too.Beware you may need to buy additional spacers to make this stem fit on your bike. Locating spacers was difficult but I found some Straightline spacers on CRC that fit perfectly.

It seems all my bikes will have a Thomson stem - I don't see buying anything else - they just work well.I'm a big guy and need parts to hold up and last - these do.Machined aluminum work of functional art.

While most of these Thomson X4 stems are used on MTB applications, they also work EXCELLENTLY on track sprint (velodrome) bikes. I have and X4 110mm on my Felt TK2. Super rigid - which is exactly what you want and need for the big gear standing starts. And, the top notch fit and finish are just the icing on the cake. As other reviewers have mentioned, this is the gold standard of stems and worth 5+ stars.

Thomson bike product! Says it’s all. As expected this is a great stem! This purchase and my Thomson seat post brings my bike closer to what I envisioned my dream bike would be! Great pickup!

Muy buen producto, se ve mucho mas robusto y resistente que mi vástago antiguo de mi bicicleta

On my 3 bike I have Thomson seat posts handle bars & stems, they are light, excellent quality & beautifully made.

poco que decir del material de thomson,yo en mi caso lo llevo en todas las bicis potencia y tija de sillin y esta ultima va a la bici de descenso para hacer el bestia y mas en trialeras y saltos,la seguridad que da thomson nadie lo hace,sera algo mas pesada pero es calidad maxima

Great stem, crappy steel bolts.Five stars for stem, One star for the bolts.I found the new Thomson bolts a much softer steel than my old Thomson Elite 25.4mm stem. The bolts are very prone to rounding out while torquing to spec (48 in/lbs) ... Note: I use only top quality, non-worn Allen, Knippix, Snapon, Mactool, etc. tools including an old bar-style non-click torque wrench. I immediately replaced the Thomson stock bolts with M5 18mm titanium bolts which worked great.Link to the To Bolts I used (color: black): https://www.amazon.com/gp/aw/d/B01G6ZXEWS?psc=1&ref=yo_pop_mb_yo_pop_mb_pd_t2Note: Ensure you grease the Ti bolt threads with a non-conductive grease or the bolts may galvanically weld to the aluminum stem over time

私の新車にぴったりです。大満足です。

正に芸術品ですね。👍