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(Summary - too big bike feels smaller with a longer stem and higher bars, very slack bike only feels right with very wide bars).
So, years ago I rode a Cotic Soul for everything and it was pretty damned cool. Then I got a Banshee Spitfire which was totally awesome. Then I tried to get a hardtail that would handle like the Spitfire but I went a bit longer and lower because of... fashion? A lot of the experimenting gave results that made sense - like set up very low and slack the hardtail was a rocket downhill but a bit of a bear in flatter singletrack. And so on.
But two recent things have surprised me: The Zero AM was feeling a bit long, despite putting a 35mm stem on it (it's not crazy long, about 455mm reach sagged and I'm about 5'11). I preferred the steering feel with a 50mm stem, so swapped that back to see how it was, despite knowing it would make the reach to the bars even longer.
So I put the 50mm stem on, and raised the bars about 10mm too by swapping some spacers. And now the bike no longer feels a bit too long, it feels pretty much perfect! WTF?!!
And the other thing - the Spitfire has a Works -2 deg headset, so the head angle is 63.7 deg (not a typo) and until last week had been wearing 810mm bars. However they don't fit through the trees here. So I put on some 750s, expecting it to feel a bit smaller and a bit less confident when going fast. And yes, it feels smaller for sure and not so good at speed - but the biggest change was that it feels wandery and difficult to control at low speed, either up or downhill. The Zero has 750mm bars and they feel fine but it's much less slack, somewhere between 66 and 67 at sag.
Anyone else noticed this? Very slack bikes needing very wide bars to work at low speed.
Just put the 810s back on - will have to slow down for the tight bits and to hell with Strava* (better make sure I don't hold anyone up though!) *There's a whole other thread on this...
The bars thing is fairly obvious.
You get a lot of flop from headangles that slack - once you start the turn, the bike wants to carry on with it, so the wider bars gives you more leverage to counteract that.
The reach? If it's that slack, then raising the stem will bring the bars towards you some? Not the full 15mm, but definitely a bit. Did you maybe roll the bars back a bit as well when you refitted them?
"The reach? If it’s that slack, then raising the stem will bring the bars towards you some? Not the full 15mm, but definitely a bit. Did you maybe roll the bars back a bit as well when you refitted them?"
That's on the hardtail which isn't super slack. Bar roll is identical, I'm very precise/anal with stuff like that.
My best guess, is that because it isn't super slack and the bars are 'only' 750 wide, putting the longer stem on slows down the steering and makes me more confident to weight the front, so my body position shifts forwards a bit more and my arms have to reach forwards less far. But I could be totally wrong.
I'm glad the extreme slackness and bar width thing makes sense!
Interesting. I recently built a meduim Zero AM with 35mm stem and 780mm bars, as that's what came along and suited the build/budget. My main bike is a medium Mk1.5 Aeris with 40mm stem and 760mm bars. I'm not sure about the handling on the Zero, washed the front out twice on first ride. I'm used to weighting a longish slackish bike having ridden the Aeris for 18+ months. Could just be not used to the AM, also running DHF rather than the Mary I've been used to recently. However I was considering trying 40/760 combo the same as I have on my Aeris, or maybe just changing one thing at a time. Think I want a bit more time on the current set up to get a feel for the new bike first so I can better understand any changes in handling.
You get a lot of flop from headangles that slack...
Less fork offset could help counter that.
My best guess, is that because it isn’t super slack and the bars are ‘only’ 750 wide, putting the longer stem on slows down the steering and makes me more confident to weight the front, so my body position shifts forwards a bit more and my arms have to reach forwards less far. But I could be totally wrong.
Yes... ish. More confident to weight the front? That's down to the rider, as well as things like seat angle/reach, depending on whether sitting or standing. Wider bars increase the triangulation of the body over the bike, bringing it forward/lower; your weight will be further back with narrower bars due to the arms being closer together as they have to 'reach less far'.
A shorter stem and longer wheelbase / slacker HA also means your weight has to move forward to maintain grip with the front wheel – it's sticking out quite a way in front. It may be you were doing this anyway, or it could be you need to consciously think about doing it (I do).
Your hardtail's angles will all also alter through the fork travel, pivoting round the back axle – something else to add to the equation.
Blimey Alex ...810mm bars on our local trails!! I'm just about managing with 750mm.
too big bike feels smaller with a longer stem and higher bars
Both stem length and bar height affect cockpit. You can fit a longer stem and raise the bars and your body ends up in the same position.
If you want lower bars for aeroness, but it feels uncomfortable, you can shorten the stem.
A shorter stem and longer wheelbase / slacker HA also means your weight has to move forward to maintain grip with the front wheel – it’s sticking out quite a way in front.
But the further out in front it is the less force it needs to exert to turn you around.
Both my Prime and my Fast Forward have 800mm bars. It can be a bit 'row, row, row your boat' in the secret singletrack, but that's part of the fun IMO, and those trails are so tight it's all slow work, trackstanding and thrutching about anyway.
All other things being equal, triangulation with your shoulders means that on shorter bars you will make space for your arms by being a bit more upright.
I suspect the bars being higher but further forwards has modified your weight distribution a touch and you prefer it. More weight on the front pins that wheel better too, so you might be getting confidence from that.
FWIW, I found the same.
Narrower bars means your body is slightly further back than with wider bars (blame pythagoras for that). Considering how important balance is on tech climbs I can imagine a small change can be enough to upset your muscle memory for a while.
But the further out in front it is the less force it needs to exert to turn you around.
True. But if the tyre isn't gripping that's pretty irrelevant. 😉
But it needs to grip less, because it needs to exert less force.
But this depends on the type of corner. The physics of different kinds of corner is different, these discussions never seem to acknowledge that.
Quick update. I've put the big bars back on the Spitfire. And just offered to buy a secondhand 2017 in a large, which has a short enough seat tube to fit my 170mm dropper and about 30mm more reach so maybe would feel right with the 750mm bars for the local trails. Will try it with the stock headset as the wheelbase and front centre will be slightly longer than my 2014 medium with the -2 deg headset.
Problem: Bars too wide for some local trails
Solution: Buy a larger frame!
Only on STW 😀 😀 😀
I wonder if lots of people over analyse Geo settings on bikes nowdays ?
"must have a XYZ top tuber..." really ? 3mm difference and you can notice ?
or "seat tube angle needs to be ..." Why ? does it really affect you ?
I tend to find I need to get used to the bike before I can really ride it - I'll chop and change bar position etc. a bit early in the life of the bike, then get on with riding it.
Nothing I have is super slack - but I can see why wider bars might work better the slacker you go (gaps between trees excepted).
muscle memory
A big part of why stuff often doesn't seem to make sense on bikes. Logic is logical, geometry and gravity is maths but muscle memory, perception and feedback loops are all subjective and variable.
I have a bike where a 20mm longer stem makes it easier to get the front up. Probably because my lever over the BB/RC area is now longer. How many of us ever look at how our bars are positioned relative to the rear axle?
Edit to add, I've had good results trying to adapt myself to a current project bike. It has geometry clashes that mean it does some things well but the fit and handling technique didn't work for me at first. No way to balance up those variables though so I did some stretching and worked on adaptation of how I initiate a corner. Now it works really well for me. My Jones was like that, demo bike felt odd to ride at first, all wrong. Then it felt interesting, then promising. Then I adapted to the bike well and found I was riding better overall (OK not 'enduro pinner' better, but a rewarding rigid bike flow and subtlety sort of better).
Part of me now thinks that subtle changes are far less important than the ability to cope with or stick with and evaluate larger changes, rather than homing in on minutae. I also think that a clever bike engineer (PVD) was right when he said that when you get close to the ideal, that's when the small changes seem big.
“Problem: Bars too wide for some local trails
Solution: Buy a larger frame!”
It was also a conspicuous bargain! 😉
I do also wonder if me getting heavier (I’ve been enjoying powerlifting) has tipped me over the cusp in terms of frame size. Obviously I haven’t got taller but my CoG has moved higher! Most people my height would have been on a large to start with. And I’ve now got more strength and weight to manhandle the bike.