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Disclaimer: Isolation has been kind to my physical health, but I may be rambling, due to my conversation being limited to my wife and 5 year old twin girls. 3 weeks and counting.
So, definitely the biggest upside to this mess so far, are these empty roads!! Wow!!!! If it wasn't for the ridiculous speeds the remaining drivers still feel the need to drive at (how is that helping anyone??????), it would almost be like the 70s. Ahhhh.... those halcyon days of drum brakes and no seat belts, when drivers had a sense of their own mortality. 🙂
Anyhow, following the advice of no Gnar, I dusted down my Planet X RT80 and started doing a solo 20 mile road loop nearly every day. Bizarrely, but brilliantly, I'm now fitter than I was a month ago!!??
I know there are lots of roadies and half roadies on here. I'd really appreciate some advice/experienced feedback please.
It appears to be upgrade time, the RT80 has been great (nothing awe inspiring, just functional), but it has rim brakes. Which I now realise are wrong in many ways and not safe in the current situation (see how I'm justifying the upgrade)!!!
So I started looking at Gravel bikes and endurance road bikes, then I realised there's even 'normal' road bikes with discs now!! Had a look at the planet X offerings like the Space Chicken, then came across the Giant Defy (seems really popular on here) and the racier TCR. Anyhow, I stuck a few bikes in the geometry geeks comparison tool, as you do... That's when things got weird!
My 56 RT80 doesn't feel in any way big. I'm 5ft 10 with a 31" inside leg. Having just looked at PX website, they are saying I should have gone for a 54 (their current chart,don't know if this has changed).
Giant say I'm a medium plain and simple. That's for both the Defy and the TCR. Spesh and Cannondale say I'm a 56.
Viewing the numbers of my current 56 RT80 against the recommended 'medium' sizing of giant and the recommended 56s of the synapse and spesh Roubaix.... My RT80 is massive! I have to sdd the size down RT80 (54) into the chart to make the numbers feel like they are a comparison of similar bikes. My current 56 RT80 is almost 18mm longer in reach than the recommended Giant Defy Medium!
So anyway what's my question, stop rambling... Should I trust these geo numbers and ignore the experts at Giant ( I mean size up above their recommendations to match my current bike)?
Having just finished a ride on the RT80, I would never think "Oh I've got to get a smaller bike". If anything, the descents feel sketchy! Hanging off the back of the seat, arse on the rear wheel... But am I just too used to the Longer Lower Slacker graduation I've been through over the last 5 years on MTB? Is Road riding different? I mean it hasn't changed in the way MTB has. The road scene from what I can gather, moves along at a much more predictable pace with innovations... I mean the roads that I ride on haven't changed in 30 years. Unlike the trails I ride on! Most of which I would not have thought possible 30 years ago. Even 15 years ago, I wouldn't have known that at 50 years old I'd be flying down Welsh mountains doing the sort of drops and jumps that I do...
I would never have known to go longer and lower and slacker, unless the R&D guys had told me to. Now I'm immensely grateful they did. So Should I trust the industry and let my body mould to the recommended size? Will it happen slowly as I put the miles in?
For reference, I ride lots of different bikes regularly. I sized them as best I could for the jobs I thought they were for, whilst using the manufacturer's guidelines.
1) Canyon Spectral (medium) - Using their very specific online sizing tool. Feels ok, but I wouldn't complain about a large and sitting even more in the bike.
2) Spesh Chisel (large). Used their chart I could have gone med or Large. But I was influenced by the desire to use it mostly for fitness... so any extra length seemed a good idea. Happy with size
3) Ragley Marley (medium). Ragley's chart said med. It was my first foray into longer lower slacker geo. Took a week.... then I was in like Flynn. Couldn't ride my other mess around bikes after that, as they just felt stupid and stubby.
4) Cotic Roadrat (medium long I think) - It's a mk 1 so I can't remember much. It's set up with risers and used for shopping etc.
Thanks for anyone that got this far... Informative answers will be even more appreciated.
Five feet ten is normally where manufacturers change over from med to large. Do you have normal body proportions? Particularly long legs or particularly long back/arms?
If you are happy with current bike fit, measure stack and reach and buy something with similar figures.
I’ve just bought a PlenetX Carbon Evo disc road bike in medium. I’m 5’10” and I feel I’m at the top end for that size.
I don't get the obsession with reach figures when it comes to road bikes. You (generally) don't ride them standing up so for me ETT is a far more useful measurement when sizing up a road bike.
I'm 5'10 with ~32.5" cycling inseam (short legs and torso of someone more typically ~6'1"), my 58cm Cube Attain GTC Pro Disc has 388/610mm reach/stack with all spacers under stem {so really 570mm stack}. 110mm stem with -6 degree. The BR505 brifters add extra reach compared to the newer 7020 brifters.
If I bought a PX Pro Carbon Evo Disc frame, I'd go medium with a 120mm stem, which would then allow me ~20cm of carbon seatpost as seat tube is 53cm centre to top. This would offer far more flex/comfort over the large frame with a 110mm stem and ~17cm of carbon seat post.
Go to a shop and try some bikes for size?
Thanks Simondbarnes, that's very useful re reach and standing up... I didn't realise that was the crux of that measurement. Makes sense as to why it's so important on mtb.
cynic-al?? Find me a shop that'll let me do that in the next 3-6 months???
Bristol is closed, for all but drop you bike off for a service, or buy online.
I’m the same measurements as the OP. I found that a 53 Kona Haole needed a 130mm stem to get the right reach. That felt great for having a small reactive bike, but at the same time I never felt confident descending. I switched to a 55 cm BMC with a 110mm stem which feels great. Technically a 56cm Cannondale would fit me but when I tried it in the shop car park I found it felt cumbersome.A 54cm C’dale felt great (as it should as it was similar to the Kona) but again would have needed a long stem to get the reach and I felt that wasn’t enough of a difference to the existing bike. In short if you have short legs and a gibbon torso then a cm or two can make a lot of difference to how the bike feels so you need to try the bikes and see. For me a 55cm bike gave me the best compromise.
Hanging off the back of the seat, arse on the rear wheel…
You're doing it wrong.
That's a much bigger issue than a few mm in size or degree of geometry.
Larger frames might leave you with little seatpost showing which might affect comfort. And also a high stack height which is a problem if you like to get low (of course you do). Hanging off the back is not the recommended way to descend on the road, weight over the front for traction and control!
Firstly there is much less variety in frame shapes in road biking because it's only endurance riding on tarmac. The most important bit is to get the seat height right, which you do by buying the right size frame and fine-tuning the saddle. Once that's sorted you can mess around with stem length, angle and bar position to get a position that suits you kind of riding and your age, hence your arm and shoulder strength and back flexibility.
As to the type of bike, I always lag behind technology - I was probably the last mountain biker to get disc brakes and suspension forks and I never made it to big wheels or any of the other fashions before moving over to the road. Where road biking is concerned I have only just sold my 2014 Roubaix SL4 with 23mm tyres and bought a 2020 Roubaix with 28mm tyres and disc brakes. The difference is gob-smackigly amazingly huge; the 2020 Roubaix is the most comfortable, smooth riding, good handling, efficient, aerodynamic bike I've ever owned. On club rides it is noticeably faster on the flat and down hills than the rest of the group; you don't need to make an effort but you just seem to pick up more speed and pass people going down hills. Even other riders have commented - I can only say it must be more aero as Specialized claim. So road bike technology IS moving on.
My only gripe is the shoddy quality of the basic level DT Swiss wheels; I've already had one new rear wheel on warranty.
Get something that’s about the right size for you that you like the look of. If you’re buying online and not sure then email the shop and ask.
Ride it for a bit. You probably won’t be out for too long on it (right?) so perfect fit isn’t the highest importance. That’ll give you a few months of getting used to it before you go and get a proper bike fit when the shops open.