an air dropper with a blow off valve
There's already a blow off valve at the top of my seatpost.
lovewookie, thanks for that link to Coast. WANT!!
Assuming a veritcal 90kg load thats 26.3kg perpendicular to seat tube.
I get 1.8mm deflection.50% more for a 27.2mm with 2mm wall thickness
Thanks, I appreciate the actual numbers but in real world terms and effect, compared to the amount of movement in saddle flex, padding clothing, skin and muscle: sweet FA.
Thanks, I appreciate the actual numbers
They're not "actual" numbers, they're educated guestimates.
lovewookie, thanks for that link to Coast. WANT!!
No worries.
I believe the rest of the range are the same as brand x, do if you want one, pressgang CRC into bringing them in. 🙂
To me, it'd be perfect for a hardtail, but in a fan of suspension posts anyway. 🙂
“Thanks, I appreciate the actual numbers but in real world terms and effect, compared to the amount of movement in saddle flex, padding clothing, skin and muscle: sweet FA.”
They’re not actual numbers and once you include dynamic loading and the big horizontal component of forces when you hit bumps, there’s no doubt that a small diameter “rigid” post will reduce a useful amount of the impacts and vibration. Any benefits are in addition to absorption from everything else.
The usual suspects here will insist that the benefits of frame and post (and wheel) flex are negligible but they’re just proving they have a poor understanding of the subtleties of engineering and the sensitivity of humans to tiny improvements.
I’d still rather have a dropper post though!
on what you want from it, super steep seat angles will suit super steep climbing, but not so just riding along the undulations.
I've never ridden a HT or FS which wasn't good on steep climbs, admittedly I haven't bought an MTB in the last 10 years, but prior to that owned / rides dozens. Is this really a problem that needed solving?
I think it depends how you pedal. I can often tell if a rider is someone I know from quite a way off by their padalling style. I think upper body lean is a big part of it, some folk like to be more upright than others. (mtb-ers that is.) I like a fair amount of lean, so I don't have issues with more moderate seat angles even on v. steep climbs.
But I don't quite get the comfort thing. Surely one is standing on the pedals long before that becomes an issue?
Is this really a problem that needed solving?
Yes! Because then frame designers can reintroduce slacker seat angles and steeper head angles with a slightly shorter reach to make bikes more 'chuckable' and 'fun' and around we come 🤣
But I don’t quite get the comfort thing. Surely one is standing on the pedals long before that becomes an issue?
I think the comfort thing comes from people who are coming off an amount of time on a FS, I get really lazy if I ride a FS for a few weeks cos you can just sit down and bounce/roll over stuff. They're not so much 'uncomfortable' as 'shouldn't expect as easy a ride over small bumps as a FS' and 'need to be ridden slightly differently to a FS'.
@footflaps - I guess the gist of what I was getting at was the possible different needs of different riders who do winch & plummet rides (say Hebden) V a more traditional XC rider (say Thetford).
Most of the geometry we are talking about will have evolved within the last 10 years or so, so you should definitely hitch a ride on a Geometron or similar to see the contrast.
If it's properly steep & off road you'll need to be seated, and thus the seat angle plays a part.
It's all horses for courses though and any bike will get you out on a ride on any terrain.
@footflaps in my experience, yes it is. Being 6'5" I have always had problems with front wheel lift on steep climbs as my weight is always very far back with the saddle at full height. Technique can help with stopping this but it only helps so much, and it doesn't make for comfortable riding when you're perched on the tip of your saddle and hunched over your bars for any extended period.
Steep seat tube angles have transformed climbing for me, along with longer reach I finally feel like bikes are being made that fit me properly which I now realise has never been the case.
Is this really a problem that needed solving?
Yes it is.
If you add length to the front centre and send the front axle even further forwards with slack head angles, then reduce chainstay length to 'make it climb better' (open to debate that one) you have a.much more rearward weight bias. Steepening the seat angle brings you forward to being more central between the axles.
But you're not likely to understand that if you've not bought an MTB for 10 years.
But you’re not likely to understand that if you’ve not bought an MTB for 10 years.
Patronising or what!
It's wasn't intended to be so. Apologies to any thin skinned types. However, HT geometry and the thinking behind it has changed a great deal in the last 3 years, let alone 10.
It's reasonable to assume, especially from the posters other comments/questions that they might be a bit out of touch.
Patronising or what!
Apologies to any thin skinned types.
Doubling down. Nicely played.
Offence is down to interpretation isn't it? Subconscious or otherwise. It's basically a choice.
If you're a bed wetting type scouring the internet for things to be offended by, guess what? You'll find offence, even where there is none.
A bit like finding sexism on toilet doors because one is for marked for gents and one is for ladies.
Do I get the triple bonus?
Yes it is.
If you add length to the front centre and send the front axle even further forwards with slack head angles, then reduce chainstay length to ‘make it climb better’ (open to debate that one) you have a.much more rearward weight bias. Steepening the seat angle brings you forward to being more central between the axles.
But you’re not likely to understand that if you’ve not bought an MTB for 10 years.
I've never heard the short chainstays make it climb better one. Though short chainstays are better for grip on slimy not-so-steep climbs where you want all your weight on the rear wheel.
Though short chainstays are better for grip on slimy not-so-steep climbs where you want all your weight on the rear wheel.
That's a pretty specific scenario to utilise as a design brief for chainstay selection!
Short stays seem to be for pop, snap and manualling reasons, in order to get a bike that feels more responsive. I get the logic and for BMX and jumpy style riders, I reckon that's what they're after, but they're less good in technical trail situations IMO, for exactly the same reasons. Depends on your priorities. It's certainly more in vogue than long stays at the moment.
In the early days of UCI and MTB I think there was a hill climb category and some of those guys had bikes with really short chainstays. I think elevated stays came about from that too.
LOL.....
What a brilliant thread!
Yeah...... you are right...... when I was out today getting covered in mud and having a hoot ragging around Haldon in the blessed sunshine I suddenly realised that my SA was 0.35 degrees too steep. God, it really brought my mood down. I came home in a real grump.
I forgot all about the Deer I saw and the fast berm at Grumpy Man's Gate that I finally nailed and the smile from that cute toddler who laughed when I pulled a big skid. That amazing hot chocolate and homemade mince pie in the hub cafe was long forgotten when I realised that my 18 year old 26" Rock Lobster Team Tig SL with newly installed 650b's would NEVER be as fun as the latest £10K superbike that MBUK or What Mountain Bike are touting as the next big thing.
God, i'm so depressed. I hate my bike. Think I might take up golf.
Think I might take up golf.
Swap seat tube angle for loft angle:
How to Determine Which Loft You Should Get on Your Driver
🤔
Simon, the reason you're scoffing at the thread is you're riding a sensible bike with a sensible seattube.
Your hardtail experience is unspoilt by modernity.
And you've retrofied your experience even further with those old French touring wheels.
If you were lumbered with one of these so-called "good" bikes, you'd be nodding in along in earnest agreement.
Mountain bikers have never had it so tough.
Hey Ned......
Are modern bikes really that bad? Have I dodged a bullet by not buying into the marketing hype regarding materials and geometry?
I haven't bought a new bike in what feels like decades as I simply couldn't afford one. (Getting my head around the nearly £2k needed to buy my first and only full-sus back in 2010 was hard enough.)
Always thought that the crop of new slack bikes reminded me of one of these:
And less like one of these:
https://www.twobros.com/products/honda-cbr600rr-2013-2016-slip-exhaust
I've tried a few modern slack bikes and could never understand or feel comfortable with the "chopper" like flippy-floppy feel of the steering.
Sounds like i've been wise in slapping a pair of 650b's on my "old-skool" hardtail.
It's great that you're happy on your old bike, but it's really not something to be all smug and superior about.
Modern bikes are just so much faster and more fun, if you ride them as intended.
yes it is
Modern bikes are rubbish.
Weirdly the hardtail I have with the slackest geometry (Stanton Sherpa) is the nicest to ride of all the hardtails I've owned, including various super-steep 26" bikes, which might have been more "nimble" or whatever, but were rubbish to ride in comparison.
And my Cotic FlareMax which is even slacker than the Stanton is a good deal more fun and capable than the Stanton (but the Stanton is still great).
I guess I've drunk too much kool aid.
Have I dodged a bullet
No, but you’ve saved yourself some money and you will never miss what you haven’t had.
