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Shimano's Tiagra FC-4700 chainset isn't going to set the world alight, but in this 48/34-tooth guise does make for higher cadence in your top gear and, depending on the terrain, less need for changing to the small chainring. If you live/ride in a fairly flat part of the country and you're in need of a new chainset it's one to consider; personally, I'd prefer a lower climbing gear too.
When we first looked at the newly designed Tiagra back in 2016, David was generally very impressed. His review was about the groupset as a whole, but he had this to say about the chainset: "This is the biggest component in terms of visual appearance when viewing a bike from the side, and it's here that Shimano has made the biggest stride forward. It has taken the same four-arm design as debuted on Dura-Ace all those years ago.
"It's available in 52/36 and 50/39/30 configurations but I suspect the 50/34 compact option I tested will be the most popular chosen by bike brands speccing new bikes. The new four-arm design has a 110mm bolt circle diameter (BCD) and allows you to swap the chainrings to any configuration, which saves swapping chainsets if you want to adjust the gear ratios. Different crank lengths are available too."
What's changed since then is that it's now available in this slightly odd 48/34-tooth pairing, which is what I've been testing.
The chainset went on my 2014 Vitus, which – contrary to what your thoughts might be regarding bike journos and all the new kit we get – was still running its original FSA Gossamer Pro compact 50/34-tooth chainset.
The Vitus had a bit of a mish-mash of parts from new – FSA chainset, Shimano 105 shifters and mechs, Tiagra cassette and Tektro brakes.
I'd changed the 10-speed cassette from the original 12-30 to 12-32 (what a difference those two teeth make), and upgraded the brakes to 105. For a while I ran some secondhand shifters, but 'upgraded' to the latest Tiagra along with new mechs at the same time as fitting this chainset.
The difference in performance between old and new chainset is, I'm afraid, hard to detect. I can't tell whether the chain moves any more or less easily from one ring to the other, and I can't say I've noticed the 93g difference in weight – the old FSA chainset it replaced was 757g, compared with the Tiagra's 850g. The latest 105 chainset is 713g.
The only 'noticeable' difference – and I have to remember to concentrate – is that I don't need to change from big ring to small as often. It depends on the terrain you're riding, of course, but it's given me a more usable range in just the big ring, with the mid-sprocket ratios lower than they were previously.
I have to say, in all my leisurely riding I haven't noticed the lower top-end ratio. I don't mind spinning along at speed but I'm not a demon racer type, and 48x12 is fine for my liking.
It didn't occur to me until afterwards, but on one stage of last year's Ride Across Britain I found it a struggle to keep up with a group who had seemed to be riding at my kind of pace, despite it being flattish, and I wonder whether that was simply down to me spinning a slightly lower gear than the rest of them. Good excuse anyway...
One thing I do really like is that the new chainset has 165mm cranks, whereas the old one had 170mm (170, 172.5 and 175mm are all available too). My custom-built Paulus Quiros has 160mm cranks, as advised by Jonathan Paulus, and short definitely suits me.
Fitting the chainset is really easy – you just need a Liam.
Liam says: "Fitting this chainset is just like fitting any Shimano crankset. It's incredibly straightforward and requires only one special tool. You'll need Shimano's tool for the bearing pre-load cap and a 5mm Allen key.
"Simply slide the driveside part with the attached axle into the bottom bracket, then place the non-driveside crank on the other side. Before you tighten the clamp bolts, you'll need to add some bearing pre-load. That's a fancy way of saying tighten the plastic cap on the non-driveside. Don't go mad, finger tight will do. Then secure the clamp bolts to 12Nm, spin the cranks to check that they're moving freely, and away you go."
Tiagra is possibly the best-value groupset in Shimano's line-up. You're getting great performance for a fraction of the cost of the higher-end ones, with just a little extra weight.
It also compares well with other sub-compact chainsets – the Miche Graff 46/30 chainset that Steve tested is lighter at 789g (though it does have fewer teeth) but costs £130, and the Praxis Works Alba M30 is lighter still at 749g, with 48/32 rings, but costs £150. FSA's 46/30-tooth Energy Modular 386Evo chainset, meanwhile, is £269.95.
Tiagra is good value for what you get, and here that's a nicely made chainset that gives you a few more usable gears in the big ring by sacrificing some top-end speed. It strikes me as quite a niche product, and debatable whether it's worth the effort to change just your big ring without lowering all your gears. That said, if you're happy with your climbing gears and don't find you're using your 50x11 (or 12) combo very often, it could be worth considering next time your chainset needs replacing. I prefer it to my old 50/34 FSA chainset, but ideally I'd like lower climbing gears too.
If you don't mind losing some top-end speed this provides a few more usable ratios in the big ring but no extra climbing gears
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road.cc test report
Make and model: Shimano Tiagra FC-4700 chainset
Size tested: 48/34, 165mm
Tell us what the product is for and who it's aimed at. What do the manufacturers say about it? How does that compare to your own feelings about it?
Shimano says: The new SHIMANO TIAGRA FC-4700 crank balances weight and efficiency without sacrificing stiffness. It is offered in 52-36, 50-34T, and a new 48-34T chainring options and 165, 170, 172.5, and 175mm crank arm lengths.
Optimum power transfer motivates riders to pedal further and faster
Optimal balance between stiffness and lightweight
Reinforced 4-arm construction
Optimized gear shape for HG-X chain
Gear combinations to match more riding styles
Additional gear combination: 48-34T
Gear combination: 50-34T, 52-36T, 48-34T
Crank arm length: 165, 170, 172.5, 175
Far too early to tell for sure, but Tiagra's not known for wearing out quickly so I'm hedging my bets that it'll be pretty long lasting.
The latest Shimano 105 chainset weighs a claimed 713g, so a little more heft here.
The Miche Graff 46/30 sub-compact double chainset weighs 789g (but both rings are smaller...).
In terms of pedalling comfort... you have more gears to play with in the big chainring, less changing between chainrings.
Cheaper than the Miche Graff 46/30 chainset at £130; and the Praxis Works Alba M30 at £150; and FSA's Energy Modular 386Evo chainset at £269.95.
Tell us how the product performed overall when used for its designed purpose
Performed well, did the job.
Tell us what you particularly liked about the product
Having lower gears in the big ring than if it was a 50/34, meaning at times I didn't have to change to the small ring. I also like the 165mm crank length, which feels more natural for me than the 170s it replaced.
Tell us what you particularly disliked about the product
That the 34T ring isn't a 32...
How does the price compare to that of similar products in the market, including ones recently tested on road.cc?
Tiagra is always seen as good value, offering the performance of 105 but for less money and just a little more weight.
Did you enjoy using the product? Yes
Would you consider buying the product? If I moved to somewhere less hilly – but I'd prefer 48/32.
Would you recommend the product to a friend? Yes
Use this box to explain your overall score
It's a well-made chainset that gives you a few more usable gears in the big ring by sacrificing some top-end speed. If you're happy with your climbing gears and don't find you're using your 50x11 or 50x12 very often, it could be worth considering next time your chainset needs replacing. It's typically good value too.
About the tester
I usually ride: Vitus Venon My best bike is: Paulus Quiros
I've been riding for: Over 20 years I ride: Most days I would class myself as: Experienced
I regularly do the following types of riding: commuting, sportives, general fitness riding,
Tass is our production pedant, who boldly goes hunting for split infinitives, rogue apostrophes and other things up with which she will not put. She joined road.cc in 2015 but first began working on bike magazines way back in 1991 as production editor on Mountain Biking UK, then deputy editor of MTB Pro, before changing allegiance to road cycling as senior production editor on Cycling Plus. She's ridden off-road but much prefers on, hasn't done half the touring she'd like to, and loves paper maps.