3T Ionic LTD seatpost review

Secure carbon post that comes in three guises

Our rating 
3.0 out of 5 star rating 3.0
GBP £199.99 RRP | AUD $325.00 | USD $270.00

Our review

Rock solid and easy adjustment once it's setup, but 3T's other seatpost options represent better value
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Most of 3T’s components come in three ‘tiers’, and its Ionic seatpost is no different. What you see here is the high modulus carbon fibre LTD version. It’s also offered in an aluminium Pro model and in a carbon fibre Team guise.


All models are available in either zero or 25mm setback, in a variety of lengths, and with either a 27.2 or 31.6mm diameter, two common sizes that will suit many – but not all – conventional road and mountain bikes. 

The 3t ionic difflock almost guarantees the seat won’t slip, while allowing for 0.5 degrees of angle adjustment – if you’re patient!:
David Rome / Future Publishing

The 3T Ionic Difflock coupling almost guarantees there’s no chance of the seat slipping while allowing for 0.5 degrees of angle adjustment – if you’re patient!

From the outside, this seatpost looks like any other single-bolt post, but there’s plenty more going on inside. The key part of the Ionic is the splined alloy DiffLock coupling, an interlocking toothed design that enables easy saddle fore-aft position adjustment without affecting the saddle angle.

Additionally, it provides a low torque clamping of the saddle rails with no chance of the saddle angle slipping.

Unlike other seatposts, the saddle needs to be removed before the saddle angle can be changed. The toothed clamp took plenty of trial and error before we found a comfortable angle, luckily you can find the right angle without fully installing the seat, instead you can just rest it on the clamp until you find the position you need.

Luckily once the ordeal of setting the saddle angle is over, back and forth saddle adjustment is a cinch. Loosening the opposing side clamp bolts lets the saddle slide along its rails and once it’s tightened, it isn’t going to budge. There’s no signs of creaking and no matter how poor our cyclocross mounts are – it doesn’t move a millimeter.

The ionic ltd features a full carbon construction; even the heads teeth that mate with the aluminum ‘difflock’ are carbon fibre :
David Rome / Future Publishing

The Ionic LTD features a full carbon construction – even the teeth that mate with the aluminium Difflock

A stiff construction means there’s no sign of flex or movement under power, but there’s also no noticeable difference in ride quality. If high comfort is a priority, there are smoother choices available.

Our zero-offset, 420mm x 27.2mm sample weighs 202g. For such a long post, this weight isn’t unreasonable, but it’s no flyweight either. Most of the weight is situated at the head in the form of the large aluminium teeth and two stainless steel bolts, so cutting the post’s length won’t save much.

The full carbon construction of the LTD is arguably stronger than the cheaper Team carbon model, which features an aluminium head bonded to the carbon post. But even with this key difference, the Team is US$125 cheaper and just 20g more than the LTD, so you wouldn’t be wrong if you’re thinking the Team is the better buy.

The 3t ionic ltd seatpost has an aggressive aesthetic :
David Rome / Future Publishing

As we’ve experienced with other side clamping seatposts, the clamp can protrude from the sides of the narrowest saddles. The saddle clamp is 57.85mm at its widest and isn’t an issue on the saddles we use, but is worth noting for narrow stance riders.  

Even at its premium price, the Ionic LTD isn’t compatible with 7x9mm oval carbon saddle rails and will need an additional item (sold separately) to make it so. It would be nice to see these small parts included, considering this is the flagship model.


Adjusting the saddle angle is a nuisance, and is the trade-off for simple back and forth adjustment. The Ionic LTD is a great looking bit of kit and is plenty secure, but at such a premium price we expected an even lower weight. With most of the weight in the clamp, the cheaper Pro and Team versions aren’t that much heavier and represent far better value.

Product Specifications


Name Ionic LTD seatpost
Brand 3T

Weight (g) 180
Independant Fore/Aft Tilt Adjustment Yes
Road/Performance Compatibility All conditions
Diameters Available 27.2mm 31.6mm