Self build gravel bike tiagra 4700 vs 105 5800

dl80

Hi,

Currently building up a gravel bike (which will be my best/non commuting bike) and have only had Sora before so looking for advice.

Have Juin tech F1 brakes so they are not required.

Hunting around the internet i can find a 105 group (in parts, without brakes) for £269 (50/34 11-28)
I can also buy the tiagra 4700 for £250 and sell the brakes, which gives more options on gearing (52/36, 50-34 11-32, 12-28)

Presumably 105 in this case seems the better value but would appreciate views on this as i have not used either.

What would you choose in this situation for a do it all bike?

roastie_cyclocross

Sorry I can't be any help as I run Sora on my CX bike, but I was looking at buying & building up a new CX frame. Where did you see 105 for £269 please, as I won't need the brakes anyway.

jp4urio

I've just bought a 5800 groupset myself, having done a tonne of forum hunting 4700 is to 95% of people's perceptions the same performance as 5800 with one gear less. The fact the 5800 series cables, which have a green hard coating around the wire cores to aid shifting, are marked on the box to also suit the 4700 series I think further demonstrates this.

However, whilst Tiagra is the only modern 10spd Shimano groupo, 105 is cross compatible with all 11spd Ultegra/Dura Ace gear. Which gives you a very broad range of cassettes/chain rings, and the ability to upgrade/replace parts later from those tiers as they develop.

Lastly for a £40 or so difference, the extra gear is likely worth it on any bike, let alone one designed for off roading.

If you were building a commuter/road bike on a tight budget then I'd lean more towards Tiagra. But for a halo bike that'll be tackling gravel I'd definitely be looking at 105.

One thing that may or may not be of use, British Cycling members get 10% off a £100+ purchase at Chain Reaction every month. I bought the 'Fan' level which is £19 on direct debit for the year, and then saved £38.79 on my basket. I bought the 5800 groupo, the cable kit, a hollowtech II BB tool, crank tool and some better cable cutters. You may also need a braze on clamp, I got the M Part one from Evans for £6.

alan_sherman

Previous advice is good. Only thing to add is that Tiagra do a triple so if you were looking at touring / wide ranging gearing spread, then that may be a bonus, or you like the middle ring for general riding!

dl80

Many thanks for the replies, 105 purchased (50/34, 11-28).

For info the shifters and derailleurs were £150, cassette and chain took it to £201 all form merlin, and the chainset with BB was about £70 from ribble, it depends what size you need, they all appear to be different prices.

roastie_cyclocross

Thanks for confirming

froze

I know you already bought the 105 but for future readers contemplating the same thing Tiagra is a very good groupset for the price, if budget is your main concern I would opt for Tiagra without question. It's a reliable groupset, it does weigh a small amount more then 105, and the brakes don't feel quite as good as 105 but that's a minor quibble. The only issue with Tiagra is that you can't upgrade to 105 when something fails later down the road whereas with 105 you can upgrade to Ultegra or DA. Tiagra does have one advantage over 105 in that it can shift a 34 tooth sprocket whereas the 105 will only do 32, so if having a lower gear is more important then Tiagra may be your best bet. The weight difference between the two groupsets is only 200 grams which is only 7 ounces which wouldn't even be noticable riding.

Speaking about brakes, quite frankly I don't like Shimano brake pads, they wear out very quickly and feel mushy in my opinion, once I wore out my set that came with a bike I bought I switched to Kool Stop and noticed a major improvement in feel and stopping power (true stopping power is all about the tires adhesion to the road surface, the better pads made that adhesion thing happen faster not better, this is a fact ignored by disk brake cultists). Of course this only applies to non CF wheels.