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Did I get the wrong size, if not, back pain ideas?

1446 Views 11 Replies 5 Participants Last post by  Bug74
Loving the general ride of the Rune (rear sus performance blows away my old coil horst Devinci), but still getting a load of lower back pain.

Always liked to ride smaller bikes (feel more nimble), and bought the Rune mainly for it's efficiency. I was hoping that my lower back pain would go away (I've already taken 4months off riding). Wondering if I'm riding too small a frame size. I'm 5'10" and riding a medium. Wondering if the slack seat angle is keeping me hunched up over the pedals, and maybe I should have gone for a large. Only problem there is the 18" seat post.

On the recovery side, I've been stretching (physio's instructions), doing Pilates and swimming. Any other ideas?

Many thanks in advance. A rather worried Rune owner, as I love the bike, but don't want to have to restrict myself to short gentle rides.
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Hey Bug,
What length stem are you running? If you are doing longer rides, than a fairly long stem is a good idea (70-90mm). Aything over 100mm tends to make you feel a little less confident while riding generally as it puts you over the front wheel more.)

Also, you should try different bar height if you have enough stearer left on the forks to use some spacers under the stem.

Also, it might be worth experimentling with saddle position by adjusting where the rails are clamped. A sore lower back tends to mean either that the TT is slightly on the short side, so maube try moving the saddle back a couple of cm and see how that feels.

I would try a few different options of stem length (maybe try swapping with a couple of mates), saddle position and stack height and see if you can find a more comfortable fit.

It will be worth putting a bit of time into finding the right setup, as you will enjoy riding so much more when you are not worrying about back pain. I really hope you find a good solution.

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Your pain from wrong saddle setup, imho. Find propper angle
Everything BTR said and adding to that.....check your saddle angle and height. In a long ride, it could spell backpain.

Does your backpain start immediatley(minutes) or after a certain hour into the ride?
Are you doing any exercises that actually strengthen the muscles in that area? You need some muscle to hold your spine up, but cycling does not develop those muscles much.
Cheers for help

Thanks for all the input.
Keith, I'm running a 75mm stem, don't want to go much longer for those pointy downhill bits.I'm also running it at 7degree rise with 2" rise Easton bars.Even at that height I still feel like I'd like to get lower to get more weight on the front for cornering.

I've pushed the saddle back in the rails, so unless I get a layback seatpost, which seems a bit unnecessary on a 71degree seat angle, it's as far as I can get.

Thanks for the input though. Bike's great, just looking forward to getting that new lower link!:)

I've tried rotating the saddle nose down to try in turn rotating my hips forward. Seems to help a bit, but still suffering. Also currently doing Pilates exercises to strengthen core muscles (not just stomach muscles!).

When playing around with back positions to feel comfortable I'm between being bolt up right (great for watching world go by!) and rotating forward but keeping lower back with a slight scoop in it. However, doing the later pushes my hands beyond the current handle bar position... quite a way beyond.

Keith, would you say that the large frame is too big at my height? Cheers.
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Looking at the Rune geometry numbers... I think the 71 degree seat angle (w/ 6" fork) is slack enough that few would benefit from moving the seat back: at least I would be too far behind the BB for comfortable pedaling.

I think you, and I, would be pretty typical height for a Medium Rune. Having long legs or long torso, or long or short femurs, might change things, though.
Everyone is different, nd what might suit one person of your height, may not suit you, there are a lot of factors to consider, not just body dimensions, but also muscle strength and flexibility. I think Pilates will help in the long term, anyone who thinks that is girly has obviously never had a serious injury and had to do some to regain core strength... it can be brutal!

If I were you I would try out all the different options as mentioned above, and also give it some time for pilates to make a difference before considering getting a large frame. however you are right... a large frame may just fix the problem right away.

One thing I would suggest is that you do not keep riding a bike that might be causing you damage.I don't want the wrong size frame to cause you long term back pain!
I agree I'll have to ramp up the Pilates to get the full affect.

Getting a large frame seems a bit extreme to me, although I'm getting fed up of riding 'lite'!

The only thing about the large frame is the stand over with the 18" TT.

I wonder if the Spitfire might help out! Any news on it?
Now seriously thinking of trading in for a large frame (although Freeborn don't currently have black Ano... and I'm away for a weeks riding in two weeks). A bit worried about stand over height with the 18" seat tube. I've got a 33" inseam. Would that be ok?

I've been testing a few bikes, just sitting on them, and it turns out that my back is actually quite long for my height. Dam more gene pool!
Hey Bug.

The standover on the large is about 25mm higher than on the medium. I hope that whatever you choose to do works for you!
I know, but ta for that. Also, sorry about the question of the headtube length, I found it on the Mythic UK site.
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