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A few months ago I moved from a 2010 Yeti ASR-5 (small frame, 26" wheels, fairly upright and racy) to a 2020 Stumpjumper (medium frame, 29" wheels, pretty slack). To say they are different would be an understatement, but it's all good.
I've spent the last 3 months making small adjustments, so far really just saddle position and handlebar length. It took me probably the best part of a year to get the Yeti just right so I'm expecting the same with this one, and they are different enough that I don't want to set the Stumpy up the same as the Yeti.
So question - on previous bikes, with steeper head angles and shorter front-centre measurements, I've always gauged reach by whether the bars obscure my view of the front hub. With the stumpy, the hub is very slightly forward of the bars, which I've so far assumed is OK since the angles are so different, wheelbase longer, etc. However I had a lunch time spin today and noticed some aching in my hands and forearms so am wondering if I've got too much weight over the front now.
I recently raised the saddle another ~5mm so that explains why now, but should I be able to see the front hub through the bars? I could either drop the saddle height a touch (but it feels OK otherwise), or try a shorter stem (currently 50mm, 35mm would be the obvious step). I'm a short arse and right between the small and medium so I'm leaning towards a shorter stem but wanted to check with the hive mind.
Ta
I’ve always gauged reach by whether the bars obscure my view of the front hub
This was never a useful gauge.
Setting up a bike is really a matter of trial and error. Try moving the saddle forward and back, spacers under or over the stem, different length or rise stems, different width bars, etc. Ten or 20 mm change can make a big difference to how a bike feels, you just have to try different setups and find what works for you.
This was never a useful gauge.
I’d maybe give it a pass on a road bike, it’s got no place off road
What the OP seems to be talking about is Effective Tube Tube, which can just be measured from saddle to bars with a measuring tape.
Reach is horizontal distance from BB to top of the head tube. If you want to measure that then a plumb line from each to the ground would do it
Can you just raise your bars a bit, the longer reach puts your weight further forward meaning you won't need bars as low as you would on a shorter reach frame to keep the front weighted
Thanks all.
Try moving the saddle forward and back
I could but saddle position is about right I think - no idea if it's correct but I've always adjusted bikes starting at feet with cleat position, heel on pedal axle for saddle height, then plumb line to front of knee for saddle fore/aft, then on from there. (micro adjustments depending on feel of course)
spacers under or over the stem
No back pain so I think saddle/bar height is OK
different length or rise stems
Not sure rise is an issue, see above, but definitely considering shorter stem
different width bars
Already taken the bars down in 10mm increments to where they feel just right. Also made sure sweep and roll is comfy.
Ten or 20 mm change can make a big difference to how a bike feels, you just have to try different setups and find what works for you.
Agree, just a 3-5mm change in saddle height is what appears to have triggered the aching!
What the OP seems to be talking about is Effective Tube Tube, which can just be measured from saddle to bars with a measuring tape
Kind of, effective top tube is the eventual measurement I'll record, and point taken on what reach actually means, but I'm just talking about whether I am stretched (reaching) too far and putting too much weight through my arms/hands as a result.
Can you just raise your bars a bit, the longer reach puts your weight further forward meaning you won’t need bars as low as you would on a shorter reach frame to keep the front weighted
I could, but at the moment it doesn't feel like bar height is an issue - I'd expect some lower back discomfort if it was too low as well as too long.
Thanks for the input all - very helpful. I think I'll see if I can borrow a 35mm stem to try for now.
Before looking at the settings, i'd ask are you just slouching on the bike, it's easily done, the way i was always taught was that you are holding on to the grips, but if you were to suddenly take your hands off, you wouldn't fall forward, so minimal pressure into the grips when in the seated position, are you needing to use your core a little more to remove the strain from your hands and arms?
Or have you got the forks set up a little hard, is compression up or too much air, so more shock going through the arms?
As always, loads of ways to look at it, but if you've exhausted all the tweaks in geometry then this might work, it is something i suffer from when going from my XC hardtail to full sus enduro, you feel a little more slouched over the bike, so easier to just let the bars take more of the weight, rather than your core and how you bend from the waist over the bike.
I’m a long way from exhausting tweaks but you make a good point. The only thing that has changed in the last 4 rides is 10mm off the bars and a 5mm or so raise of saddle height. Saddle height was changed prior to today’s ride so I’m pretty sure that’s what’s triggered it, throwing me forward just a bit more than before. Maybe I need to give it a while and see if this is either a one off, or my core picks up the load. I’m generally not slouchy as I ride a fair bit of road so core is strongish and I am usually in a more aero/aggressive position for that.
I usually have 3-4 rides between very minor tweaks just to let things settle down.
Thanks
plumb line to front of knee for saddle fore/aft,
This is another traditional setup trick that tells you nothing useful. The point of modern geometry MTBs is they have a steeper seat tube to put you further forward over the pedals for climbing, plus a longer reach and shorter stem. If you set your bike up using the knee-over-pedal method, you'll need a layback seatpost to slacken the effective seat tube angle enough to get it back to where you're accustomed to. If you manage to achieve that, you'll end up with an effective top tube that is much too long so you'll have to stretch forward to reach the bars.
Ignore the old ideas of knee over pedal and the bars lining up with the hub, they were never useful setup guides for MTBs and they won't work at all with a modern geometry bike - you'll probably have to buy a frame that's two sizes to small. If the bike feels too long, move the saddle forward and see how it feels to ride. If it still feels too long, try a shorter stem.
That's really interesting, thank you. It seems the world has moved on without me realising, I must be getting old 🙂 I'll take the saddle forward a touch and see how it feels.
I went looking for more info and found this which is very interesting, the section on effective seat angle talks a little to what you explained above.
https://www.bikeradar.com/features/the-ultimate-guide-to-bike-geometry-and-handling/
I'm interested to know if there is anything more to consider on overall rider efficiency, along the lines of saddle fore/aft/height affect the amount of power you can deliver. Just out of interest rather than looking for tiny marginal gains. If anyone has any links please share.
I’ve always gauged reach by whether the bars obscure my view of the front hub
I can see my headtube badge on both of mine!(just)
Bar height. As has been said, long bikes don't need you hunched over the front.
Your 'feels just right' is based on what it should feel like on a short, tall, twitchy bike from 11 years ago. Its old skool dogma that is difficult to break. Been there.
Next, despite being able to pin the corners, and 'feeling just right' you'll wonder why it feels a bit dead and slow in flicky, high speed left-right scenarios.
Next, despite being able to pin the corners, and ‘feeling just right’ you’ll wonder why it feels a bit dead and slow in flicky, high speed left-right scenarios.
Yes. I think I’m there already. So what’s the answer in your opinion? Also move saddle forward?
Just in case anyone is interested..... I took the saddle forward 5-10mm and got out today for a ride, it felt like I was pedalling more efficiently and I think also felt marginally better on twisty flat singletrack with seated pedalling.
I was also quite conscious of the other comments about raising bars and shorter stem and was trying to imagine how those changes might feel. I'll not make any more changes just yet but I do have a 5mm spacer on top of my stem so might move that under as the next change. I've a 35mm stem ordered too so will try that once everything else has settled down.
Thanks again for the feedback folks.