29er sizing

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OP
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2pies

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Location
Brighton
Im 5ft 10 and a 17" 29er frame just about fits - stand over height is right on the limit

Should have had a 15" one really

Interesting. Like you, I plan on using it to commute on it, as well as single-track.

Thanks for the advice all.
 
OP
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2pies

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Location
Brighton
Really struggling to find a bike that is a suitable size and has decent components on it. I don't like to compromise!

The bike that I like the most is the Boardman 29er Pro. Its spec is heads and shoulders above every other bike on the market that I can find e.g. Rockshox Reba fork, Deore gears and brakes, carbon post, Mavic wheels etc. Its also in stock, the other bike that caught my eye is the Trek X-Caliber 9 but that is completely sold out in the UK.

However, it only comes in Large, not X-Large. That said, Boardman Large isn't far off most other brands X-Large. The Top Tube, which I'm lead to believe is the key measurable, is 630mm, compared to 610-620 on most other manufacturers Large size. X-Large is typically 640-650.

So I wondered, is the extra 1cm or so really going to make that much difference? And, if it did, would replacing the 70mm stem with a 90mm suitably compensate, or would that have an impact on the ride?

What I really want to know is, what would be the impact of riding a bike that is slightly small for me in a) commuting scenarios e.g. 30 miles a day on roads and b) light to medium off-road e.g. 3 hour blue/red trails.

Or, is the difference in components on something like the Spesh. Rockhopper (own brand wheels, Tektro brakes & Suntour fork) pretty marginal?

Apologies for so many questions. I just don't want to feel compelled to buy an inferior bike just because the manufacturer has labelled it as X-Large.
 
The Large Boardman is quite similar in dimensions to the Large Kinesis ff29, a spec page I'm used to looking at. You could almost certainly tweak things like bars, stem and stack height (Boardman seems to have about 2cm of adjustment maybe more). It's a lovely bike but I'm partial to the Boardmans.

The issue I would have with using one for dual purposes is that the setup I'd want for road riding, tyres, stem length, bars, stack height would be quite different to what I'd want off-road. On road I'd like the bike to be longer and lower and off-road shorter and higher. Personally I think it's a circle you won't square, you'll have to compromise.
 
OP
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2pies

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Location
Brighton
The Large Boardman is quite similar in dimensions to the Large Kinesis ff29, a spec page I'm used to looking at. You could almost certainly tweak things like bars, stem and stack height (Boardman seems to have about 2cm of adjustment maybe more). It's a lovely bike but I'm partial to the Boardmans.

The issue I would have with using one for dual purposes is that the setup I'd want for road riding, tyres, stem length, bars, stack height would be quite different to what I'd want off-road. On road I'd like the bike to be longer and lower and off-road shorter and higher. Personally I think it's a circle you won't square, you'll have to compromise.

I can't imagine changing tyres and stem would take too long. I could live with half an hour of adjustments before taking it off-road every other weekend (which is what I'm likely to be doing) . If that's all that was needed.
 

young Ed

Veteran
I can't imagine changing tyres and stem would take too long. I could live with half an hour of adjustments before taking it off-road every other weekend (which is what I'm likely to be doing) . If that's all that was needed.
if you had the money you could get a separate set of wheels for off road and one wheel set for road
have wheels suited for each rather than a compromise and makes changing for the weekend quicker
Cheers Ed
 
I can't imagine changing tyres and stem would take too long. I could live with half an hour of adjustments before taking it off-road every other weekend (which is what I'm likely to be doing) . If that's all that was needed.
Young Ed makes a good suggestion but in answer to your earlier question, a smaller frame just puts you more upright and combined with a slacker head angle on the mtn bike will just make it all feel a bit slower on the road, quite different to a road bike. Going for a more stretched ride on a larger frame will make it more difficult to move the bike around off road, that's your main compromise. Within either of those two scenarios you have the ability to fine tune the setup.

If I was going to do a lot of mixed trail riding on choppy routes I'd want the smaller frame whereas fast flowing stuff I could probably get away with a bigger frame. There is no hard and fast though, practically you might find one size just fits and the other feels wrong, this is all just theoretical.
 
OP
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2pies

2pies

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Location
Brighton
Young Ed makes a good suggestion but in answer to your earlier question, a smaller frame just puts you more upright and combined with a slacker head angle on the mtn bike will just make it all feel a bit slower on the road, quite different to a road bike. Going for a more stretched ride on a larger frame will make it more difficult to move the bike around off road, that's your main compromise. Within either of those two scenarios you have the ability to fine tune the setup.

If I was going to do a lot of mixed trail riding on choppy routes I'd want the smaller frame whereas fast flowing stuff I could probably get away with a bigger frame. There is no hard and fast though, practically you might find one size just fits and the other feels wrong, this is all just theoretical.

Appreciate all of your advise. You've obviously got a fair amount of experience and knowledge on the matter.

I'm not quite sure what you're ultimately suggesting though:

  1. Roll with a smaller 29er frame, with better components, and make adjustments as and when
  2. Compromise on the finishing kit, in favour of a 29er frame that is a more suitable fit
  3. Look at a more dual-sport focused bikes
 

ScotiaLass

Guru
Location
Middle Earth
As I don't ride technical anymore I went for the slightly larger frame and more upright position.
I think you have to go with what's comfortable and suits your style of riding :smile:
 
Appreciate all of your advise. You've obviously got a fair amount of experience and knowledge on the matter.

I'm not quite sure what you're ultimately suggesting though:

  1. Roll with a smaller 29er frame, with better components, and make adjustments as and when
  2. Compromise on the finishing kit, in favour of a 29er frame that is a more suitable fit
  3. Look at a more dual-sport focused bikes
I wasn't really coming down in any direction because I think that's ultimately your call, just trying to present as many sides of your options as possible.

If I have to make a call I'd say you're buying this because you want to ride off-road so you're already compromising your road riding for that reason, therefore go for the large frame with the Boardman sizing as from what you've said this will probably be the best fit. The extra large size in other makes, like your shirts you mentioned will probably swamp you for reach. As ever, it would be best to try one if you can and if not, be guided by what you've already ridden and found comfortable i.e the 650b you mentioned.

Ultimately, provided it fits you it won't be wrong just different. I had a 1997 Marin bear Valley which was a long low mtn bike, a rigid one. I used that for blue and red trails and general XC. Only last year did I move to a new 29er with suspension which is far better for today's trails and the Marin will become a tourer as it's perfect for it. So no matter which bike you get you'll still be able to use it for either purpose. There is no wrong decision, just a choice.

As for the bike, provided the budget fits and there's no major spec differences, be guided by what you'll look forward to riding, ultimately that's what I bought, the bike I fancied.

Last point, a lot of mtn bikes will not take a rack except a seatpost one. That Boardman for instance, has no rack fittings on the rear stays or dropouts. Dunno if that matters.

For spare wheels, look at Superstar or Chain reaction. A spare set of 29er wheels could be had for about 130ish.
 
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2pies

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Location
Brighton
The comment about not comprising was more about the components than a particular style of riding. I bought a road bike a few years back in a hurry, because the one I wanted wasn't available at the time and I really regretted it.

I take your point on other matters though.

I popped into Halfords on Saturday and they were surprisingly helpful and, while not as knowledgeable as someone who might work in a smaller LBS, was able to answer most of my questions.

I sat on the Large Boardman and it felt OK. Probably just about right for off-road, though its hard to say without going over a few bumps. I then asked to put a longer stem on it and the salesman happily obliged. The reach felt better, but still not perfect. I then asked him to remove all of the spacers to drop the bar by about an inch. That felt much more comfortable for general road riding, which I would use it for immediately. I'd imagine that some gentle rides in parks will help me find a comfortable position for off-road, whether its with the shorter or longer stem.

All in all, I just really like that bike for a number of reasons - good components, nice finishing, gear ratios that appeal to me and simple to buy a Boardman bike using the Halfords C2W voucher that my company uses.
 
When I bought my Boardman from Halfords they set it up on a turbo for me so I could get the feel of "riding" it. It's not leaving the shop so in theory no reason why they wouldn't do this for you. I suppose it depends on how helpful they feel like being!
 
OP
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2pies

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Location
Brighton
When I bought my Boardman from Halfords they set it up on a turbo for me so I could get the feel of "riding" it. It's not leaving the shop so in theory no reason why they wouldn't do this for you. I suppose it depends on how helpful they feel like being!

Yes, its an odd policy not to allow customers to take a bike out even if its just in the car park. I even offered them my iPhone & credit card but they didn't budge. I suspect they have had their fingers burnt too many times. That said, it was quite a large shop so I road up and down a couple of aisles (felt a bit silly doing so) but gave me the chance to stand on the pedals and put some force on to the forks, after which they adjusted the air pressure to match my weight.

All said and done, the chap I spoke to went out of his way to be helpful. I had expected an apathetic youth with no more than a basic understanding of components & frame sizes.

Perhaps he enjoyed talking to someone about decent bikes. Most of the people in the shop were looking at toddlers bikes with stabilisers or the absolute bargain basement Carrera and Apollo hybrids.
 
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