Kindergarten geometry playground
Posted: Fri Nov 27, 2020 1:56 pm
Enough thread hijacking.
Here's our own kindergarten playground.
for my trip across the Puna de Atacama I rode the above mentioned fatbike. The front is long enough, the seat tube angle steep enough to put quite some load onto the wrists.
I agree with
Unless, I use a higher riser bar. It's that easy and exactly what I did and have mentioned before too.
Infact, I've dropped the additional 5 mm rise back to where it was before with removing spacers from below the stem so the bar height is were it was before.
The way the bar input translates into bike behaviour is fantastic.
I remember riding a mate's Bombtrack (Beyond+ IIRC) with Jones' H bar - the first time I felt comfy holding an H bar (as his bar ends pointed downwards) and found the steering sensation quite different, special, even exciting and suddenly saw the appeal.
The pivot was about level with my hand position.
This translates lovely across other bikes, also one with a 7.6 cm(!) longer reach since a stumpy 20 mm stem, a 9 ° backsweep has a much related feeling, yet is super easy to control when things get rowdy.
Then there's the often fashioned (on mtbs) short seat tube topic.
I'd be happy with a 480 mm seat tube on a bike I don't use for steep stuff, but more the kind of offroad riding of everyday use or some irregular (except perhaps for 2019) offroad travelling. Yet, why bother with a long seat tube, when I can go short on it and get it out of the way for the steep bits and but use a long seat post instead with will also add to comfort which may have gotten lost with a steep seat tube angle (especially in the era of dropper posts with > 180 mm stroke).
31.6 mm seat tube diameter (which will allow almost all available seat posts, dropper or not) and use a 27.2 mm thin one (eg Waltly, they make some lovely ti posts which are reliable) with a plastic reducer sleeve for touring comfort.
I'm at a point where I feel like this about my Krampus (2017, same geo as today's)
Thankfully things can be tweaked and when I ride only this bike for a week or two, it begins to feel mostly okay again.
The power of habit.
I've seen a few to just roll across the car park and come back to describe how the suspension behaves.
The bike I can ride fastest doesn't feel good in a car park, it feels harsh. Once on single tracks at a certain pace it comes to life, builds grip, holds lines.
So I had a look at the numbers of the old Pugsley and the newest version.
2011, 20" 2018, 18.8"
Seat tube [mm] 508 478
Top tube actual [mm] 582 591
Top tube effective [mm] 610 620
Head tube angle [°] 70.5 69.5
Seat tube angle [°] 72 72
Bottom bracket drop [mm] 55 65
Chainstay [mm] 448 460
Wheelbase 1097 1127
Head tube [mm] 130 145
- 3 cm for the seat tube.
+ 1 cm for the top tube
- 1 ° for the head angle
no change in seat angle
- 1 cm for the bb
longer chainstay, but that's to accommodate larger tyres.
+ 3 cm for the wheelbase
+ 1.5 cm for the head tube
That's a conservative change over something like 7 years or so. Yet we see the frame got longer and a little slacker.
Then, for more extreme changes, look what Salsa has done to their trail bikes (which seem to be loved by bikepackers unisono).
This also applies to oh so many other brands. Be ready to embrace the changes and ride bikes which will become longer, lower and slacker.
I'm warning you, you might even like it
From another thread:
Here's our own kindergarten playground.
You may want to re-read and find that perhaps you have taken my words out of their context:
Alpinum wrote: ↑Wed Nov 25, 2020 8:37 am[...]
I have a Surly Krampus and a Pipedream Moxie. Both will take a 27.5 x 3" tyre.
My Moxie will just about take Maxxis 27.5 x 3" tyres on i35 mm and the newer Version have 10 mm longer chainstays, so have a tad more space. I can highly recommend this bike. A real 3" on a 40 mm rim may not fit though.
Most will be fooled by the numbers of the Moxie, but they just don't know it better and haven't tried how it actually rides.
10 x more fun to ride on any terrain than the Krampus. Frame finish is a different class too.
Surly is just cheap made stuff sold expensive thanks to good marketing and courage.
I know a few who ride Nordest Sardinha and say good things about it. Same for Kona Unit and Honzo.
A mate rides a Stanton Sherpa, likes it too.
Another got a Tumbleweed Prospector, but isn't too happy with it, huge amount of clearance with 27.5 x 3". He might sell it.
I rode some of the above and Kona Honzo amd Stanton Sherpa where by far the best feeling bikes. Fun inducing, simple and pure fun and comfy geo for long rides. Especially with Kona you get loads of bike for the money. The Tumbly Prospector rides awful and is expensive for what you get.
[...]
Indeed. After some riding (3 years) with bikes with both, more laid back (72 something °) and a steeper (I have three bikes with ≥ 76.5 and 77 °) seat tube angle I find the steeper STA a prime example for how touring bike's geo can benefit from mountain bike's geo;jameso wrote: ↑Thu Nov 26, 2020 5:56 pm The steeper STA aspect of LLS bikes for longer, more seated MTB/off-road touring riding can be tricky, or at least by the time a STA is steep enough to aid climbing it's putting me out of balance on flatter open trails that make up enough of my riding for it to be influential in comfort
for my trip across the Puna de Atacama I rode the above mentioned fatbike. The front is long enough, the seat tube angle steep enough to put quite some load onto the wrists.
I agree with
Unless...
Unless, I use a higher riser bar. It's that easy and exactly what I did and have mentioned before too.
For the first two years on the Moxie (size Longer, 510 mm reach, 76.6 ° seat tube angle) I rode with a 32 mm stem and 20 mm riser bar at 770 mm width. Not too long ago, I changed to a 20 mm stem and a 25 mm riser bar at 800 mm (which might get cut down, but currently too comfy with it...). Besides the not so subtle changes in handling, the bike has become absolutely long distance capable. Riding it before stumpy stem had required a lot of core, shoulder and upper arm strength. With only backing reach + stem length off by 12 mm I get both, an agile feel and stable ride at high paces.Alpinum wrote: ↑Thu Nov 26, 2020 12:45 pm Rode this for most of the time during a 6 week holiday. Fully loaded, high handlebar position. I've never ridden in so much comfort. Lovely.
Rode it later lightly loaded, lower handlebar position. Still lovely.
Thanks to the short ht I can adjust bar height freely (opposed to most touring bikes) and fit any type of fork to the bike.
Infact, I've dropped the additional 5 mm rise back to where it was before with removing spacers from below the stem so the bar height is were it was before.
The way the bar input translates into bike behaviour is fantastic.
I remember riding a mate's Bombtrack (Beyond+ IIRC) with Jones' H bar - the first time I felt comfy holding an H bar (as his bar ends pointed downwards) and found the steering sensation quite different, special, even exciting and suddenly saw the appeal.
The pivot was about level with my hand position.
This translates lovely across other bikes, also one with a 7.6 cm(!) longer reach since a stumpy 20 mm stem, a 9 ° backsweep has a much related feeling, yet is super easy to control when things get rowdy.
Then there's the often fashioned (on mtbs) short seat tube topic.
I'd be happy with a 480 mm seat tube on a bike I don't use for steep stuff, but more the kind of offroad riding of everyday use or some irregular (except perhaps for 2019) offroad travelling. Yet, why bother with a long seat tube, when I can go short on it and get it out of the way for the steep bits and but use a long seat post instead with will also add to comfort which may have gotten lost with a steep seat tube angle (especially in the era of dropper posts with > 180 mm stroke).
31.6 mm seat tube diameter (which will allow almost all available seat posts, dropper or not) and use a 27.2 mm thin one (eg Waltly, they make some lovely ti posts which are reliable) with a plastic reducer sleeve for touring comfort.
I feel many don't get this. Feels odd – is rubbish.
I'm at a point where I feel like this about my Krampus (2017, same geo as today's)
Thankfully things can be tweaked and when I ride only this bike for a week or two, it begins to feel mostly okay again.
The power of habit.
I've seen a few to just roll across the car park and come back to describe how the suspension behaves.
The bike I can ride fastest doesn't feel good in a car park, it feels harsh. Once on single tracks at a certain pace it comes to life, builds grip, holds lines.
Interesting, lets pick the conservative numbers of a Pugsley and compare old vs. new.
So I had a look at the numbers of the old Pugsley and the newest version.
2011, 20" 2018, 18.8"
Seat tube [mm] 508 478
Top tube actual [mm] 582 591
Top tube effective [mm] 610 620
Head tube angle [°] 70.5 69.5
Seat tube angle [°] 72 72
Bottom bracket drop [mm] 55 65
Chainstay [mm] 448 460
Wheelbase 1097 1127
Head tube [mm] 130 145
- 3 cm for the seat tube.
+ 1 cm for the top tube
- 1 ° for the head angle
no change in seat angle
- 1 cm for the bb
longer chainstay, but that's to accommodate larger tyres.
+ 3 cm for the wheelbase
+ 1.5 cm for the head tube
That's a conservative change over something like 7 years or so. Yet we see the frame got longer and a little slacker.
Then, for more extreme changes, look what Salsa has done to their trail bikes (which seem to be loved by bikepackers unisono).
This also applies to oh so many other brands. Be ready to embrace the changes and ride bikes which will become longer, lower and slacker.
I'm warning you, you might even like it


From another thread:
I understand this as a rhetorical question and like the statement behind it.johnnystorm wrote: ↑Fri Nov 27, 2020 11:40 am Perhaps the trail geo of the other two aren't a barrier to traipsing into the wilderness?