[Closed] What makes a bike a good/bad climber, part whatever

Pedal efficiency of the system maybe?

A steeper seat angle makes a difference.
Less power being wasted in the suspension also makes a difference.

Tyre pressures - carcase stiffness.

Your own rollercoaster of dynamic FTP and leg freshness?

Wheel weights?

The reason I picked this particular comparison is that it's the one where I have enough samples to deal with variations in my fitness. I looked at climbs of over 20 minutes (to rule out short bursts of effort compensating for differences) and restricted the analysis to climbs where I'd done at least 5 attempts on each bike. There wasn't a single one where the FlareMax got within 5% of the Five on average.

The Five pre-dates the modern fashion for steep seatposts. It was a "true" 73 degrees. The FlareMax claims to be 73.6 degrees. I've also got the saddle mounted a bit further forwards on the FlareMax so I doubt it is any less steep in practice.

"Pedal efficiency of the system" yes, probably, I'm just not sure which part of the system as I can't see any part where the old Five should have an advantage.

Wheel weight? That did cross my mind. It would make it feel less snappy, which is why I wanted to check the stats to see whether what I felt was actually real. But on a longer sustained climb that should have less of an effect and be compensated for by the better rollover. There aren't many XC racers left on 27.5" after all even though those wheels would be lighter.

The ebike forums are always banging on about shorter chain stays make better climbers

Well at 425mm the Five certainly had much shorter chainstays than the FlareMax (448mm). I thought longer chgainstays were better for climbing though. Keeping the front end down. Mind you road bikes are sub 420mm and they climb OK. I can see that longer might lead to more flex, but nobody ever called the rear of a Five stiff. It's a possibility though.

I wouldn’t rule out tyres. Mary is a pretty draggy thing even on the front. Compound also makes a difference. Rock razor looks fast but what compound is it?

Different gearing may explain it. Newer bikes with dinner plate sprockets encourage you to sit and spin away gently while with older bikes you had to put in more effort to keep spinning.

Group ride vs solo, summer v winter, trails deteriorating....... list goes on.

Even thing like bar position can make a difference. There are loads of small variables.

I found my fastest climb on a short steep road hill was on my hybrid bike, not my light carbon road bike. Basically because it had wide mountain bike handle bars. Nothing to do with gears, frame, modern geometry, expensive components etc.

Drive train losses? Clutch mechs, narrow wide chainrings and a horrible chain line in climbing gears on modern bikes can't help.

I gave up on trying to predict this when I got my Ragley Ti- still the best technical climber I've ever ridden, and a very good nontechnical climber, even though it was considered to be basically a descender. I've done stuff like adding anglesets to one bike which made it climb better, and then doing the same on another that made it worse, even though they were overall a pretty similar shape... And on paper my Remedy should be a better climber than my old Trailfox but it's just adequate... And linkages + modern shocks introduce so much power for change that you can't really predict outcomes.

And that's even before you stick a lump of flesh controlled by a meat computer on top and it feels tired when climbing because it's worrying about whether it locked the house door, or pedals like an absolute beast because the trees smell nice

jamezee
Full Member

Drive train losses? Clutch mechs, narrow wide chainrings and a horrible chain line in climbing gears on modern bikes can’t help.

None of these things will make a difference you can measure. (and chainline's no different than using teh middle ring on an old bike, which was always fine)

I guess tyres would be an easy enough one to check. Compounds are pretty similar. Pacestar/Trailstar vs Speedgrip/Soft

For the rest I think I’ve got enough samples to average them out. It’s not a rigorous statistical analysis, but there are over 50 runs on each bike over a mixture of climbs. I’m pretty confident that the old Five climbed faster than the FlareMax, I’m just not sure why.

I would say that the 26" wheels are faster uphill, you heard it here first.

Rotating weight is everything on climbs. 2lbs difference and some of it in the wheels will hurt!

You can never rule out the fleshy lump on top of course. It is true that the FlareMax feels a lot more stable at really low speeds and maybe that encourages a “take it easy” approach. I don’t think that’s it though, or not all of it. Sometimes I try to give it the beans but it just seems that the more effort I put in the less efficient it becomes.

If you want something really weird though, I’m pretty sure that the best climbing bike I’ve ever had was my 4.8” steel fatbike. It weighed a ton. I think each wheel weighed over 2kg and yet it still hold the PR on lots of climbs and is within a few seconds of my best time on a few others. That was fully rigid though and was pretty much the only bike where I could get out of the saddle without feeling like I was just wasting energy. As @Northwind said though, there is no logic to it. I replaced that with a lighter carbon fatbike running the same wheels and it was slower ! That’s old news though. I did a thread on that one and although I never got to the bottom of it it’s the FlareMax/Five comparison that is doing my head in now.

The Five was hardly known as a great climber after all.

My mate's a mountain goat & always leaves me for dead (but so does everyone nowadays) his 2013 5 was the best climbing bike he'd ever had. We both had 5's but he had 150mm on the front & mine's 140. He's now on a Bronson C & he says the 5 was just as good a climber. In fact the only thing he reckons is better is the grip he gets on muddy descents but that could be cos he's got 2.3 tyres on & not 2.1 Maxxis Advantages.

Yes, maybe the only conclusion we can really draw from all this is that the old Five wasn’t the bad climber peopled liked to say it was.

Also, nobody seems to care about climbing speed on trail bikes these days so it’s not surprising that modern trail bikes are biased more towards the descents. The FlareMax is a perfectly pleasant place to be on the climbs and is so much more capable than that old Five on the way down. That’s what people want I guess and it is only weirdos like me who care (or even notice) that it’s actually a bit slower on the way up.

I do still wonder if there is anything I could do to get that 5% back though.

Would the CC shock make it climb any better than the X-fusion? I could just whack a load more air in and see if that made any difference.

Would faster tyres (say racing Ralph and nobby nic in speedgrip) actually gain enough to make up for the reduced confidence on the way back down? Only one way to find out I guess, but not while the trails are like they are now.

Depends what you class as a good climbing bike?
My Geometron is pretty slow on fireroad climbs but I can get up steeper and techyer stuff on it than I could on previous bikes.

I love climbing and am pretty fast (60-odd climbing KoMs if that counts for anything) and I’ve been pondering similar anomalies to yours.

I currently ride a Bronson 2 which climbs OK. Previously I had a Yeti SB75 which climbed well. I still can’t match some of the times I set on the Yeti despite gaining fitness this year and losing 6Kg from my already light frame (6’2” tall and 67kg). On the other hand, some climbs I’m relatively effortlessly faster on the Bronson. I think those are the ones where traction is king. The Yeti’s Switch rear suspension may be doing something similar to that on your Five, i.e. becoming less active under power and so providing a better pedal platform on smoother climbs. The VPP on the Bronson should do something similar but it feels noticeably more active which provides great traction but reduces all-out speed.

I’ve recently been experimenting with chunkier tyres on the Bronson and I’ve fitted heavier wheels having destroyed two sets of lighter wheels up here in the Lakes. Although the wheel/tyre combination adds only 800g, apparently a small amount in the overall system weight, my climbing times have bombed and it feels like hard work! On the mile long climb up to Tarn Crag from Miller Bridge on the outskirts of Ambleside, I can’t get within 30 seconds of my time on lighter wheels and tyres and I’m generally over a minute slower. Amazing and difficult to explain from a pure physics perspective!

Had a feeling OP had a similar quandry about two fatbikes, with the lighter Canyon Dude being slower...

What were the conclusions from that comparison and can they carry over to this scenario?

What about your riding position? More upright and arms wider on the newer bike?

Also, are you using the same pedals/shoes on both? My Patriot was always a bad climber but I think it's significantly worse now I have flats on it.

Tyres - weight and compound. You used to be able to get decent XC/AM tyres at around 550-650g. They’re now almost always over 1kg.

Going uphill you’re, especially off-road, having to constantly accelerate that weight as it will quickly lose any momentum.

It sounds as though it might be worth trying some lighter tyres when Spring comes, just to see if it does make a measurable difference. I might try over-inflating the shock as well just to see if I'm losing a lot of energy there or not.

That stiffening under load that the Five used to do could well be it though. I was running a double back in those days (remember those) so in the granny ring the chain was a fair way below the pivot. The FlareMax is 1x and even with a 30T up front it's only just below the pivot. Maybe I just had a load more anti-squat in the granny gear on that old Five.

I never did solve the Dude vs Ice Cream Truck mystery though. There was some discussion about the flex in the steel frame and how that might smooth out the power delivery. It seemed far-fetched, but I never found a better explanation.

I have the same bars on the FlareMax that I used to have on the Five and tried to get them at the same height (allowing for smaller wheels etc). I'm also using the same (flat) shoes and pedals as I used on the Five. I've never really found that clipless gains me much, but I could try popping the spds from the gravel bike on to see if that makes any difference I guess.

i changed one tyre and both wheels on my chameleon and saved 800g. transformed the bike from something 'ok' in to something downright fun. no way would i go back. it was a lot of pounds spent to save pounds but worth every penny.

i know the cotics are popular but doesn't it have it's own gravity well? 😉 maybe that weight that 'doesn't make a difference' actually does? mate of mine who i think i only ever beat on the climb up to the local spot on singlespeeds once (perhaps after injury too IIRC) has one and in his words 'love it, but it's not a climber'

if that solution is too simple i'd just say the same as some of the others. humans are complex engines with many factors at play.

probably the only real way is some bro-science PB style. power meter, fixed distance, same tyres, same pressures.

It was a lighter bike that had a better pedal response.

The other things people have mentioned may be minor factors, but those are the two main ones IMO.

I n r a t s but have you ruled out that you weren't fitter when riding the old bike?

I know you've got a decent sample size, but you sure the weather conditions are comparable? In my experience wind is the biggest factor in otherwise apparently random climbing times, most noticeable on road admittedly.

I'm sure he would have noticed the wind..

Mike Levy just did a vid on efficiency comparisons on ten bikes. Didn't really delve into too much detail about the whys, but interesting anyway.

I think the biggest factor is time, as in you are a 5 year older fart.

Comparing climbing times is interesting though. I'm often amazed. I can do a ride and think. Shit that was slow and then see after I have just done a really fast time.

My conclusion is that your head is the biggest factor of all and what the clock says is totally irrelevant. It's all about how it feels which is far more important

Without a power meter I don’t think the data is of any use - I can’t believe that the Cotic could be 5% less efficient with its bigger wheels, similar seat angle and fairly high anti-squat. The pinkbike efficiency test is an interesting watch!

You’re probably enjoying the climb more and hurrying less. 😉

I think the biggest factor is time, as in you are a 5 year older fart.

That was my initial thought but he said he is now fitter than before?

I have definitely gone over the hill at 53 and my times (especially ling climbs) that I did when I was 45 are a distant memory and I can't get close to them even though I have done the same amount of cycling in those 8 years. Being that much older just feels like I have less energy to power uphills.

A longer frame will probably put you in a less efficient climbing position as there's less room for your lungs to open up, and your hips are more bent. Aero and weight distribution doesn't matter on a grinding climb

Thanks for all the comments. I can fully understand the scepticism. When the numbers don't show what you expect you are quite right to question the method. Personally I'm confident that there is a real difference between those particular bikes, but I'm also quite content if you don't believe me. You could be right and I'm certainly over the hill. It could also be something as simple as a faulty shock.

You’re probably enjoying the climb more and hurrying less.

This is definitely part of it. The Cotic is very stable and does encourage me to just take my time. I've also managed to get up climbs that I never managed on the old Five, mainly because I took it easy at the start and still had something left for the tough part. So it's not a bad climber, it's just not a fast one.

That PB video was interesting thanks. I'm not really convinced that a power meter makes the test that much more valid though. What is the variability on these? It only needs to be a couple of percent to invalidate the results.

To be clear, I'm not really criticising the Cotic or trying to make it into a climbing demon. There are lots of trade offs that go into making the ideal bike for each of us. Nor would I want to go back to the old Five. Yes, it was more fun on the climbs, but I broke both arms in separate crashes less than a year apart, which was less fun. Of course you can never blame the bike for a crash, but the extra margin for error on the FlareMax is a huge plus for me as I do most of my riding on my own in fairly remote places and it more than makes up for the slower climbs. I'd still be happier if I could make the climbs a bit easier though 🙂

The difference between Summer and Winter is massive. I did a recent ride trying to replicate a 30km ride that I did on a VERY dry day in Spring.
Within the same time I managed about 10km. Turned back really early. Out for 2 hours both times.

I would say that the 26″ wheels are faster uphill, you heard it here first

Everything offical says 29" is fastest. Yet they are heaviest - doesn't make sense

It was a lighter bike that had a better pedal response.

This. I think 2lb of bike weight, particularly rolling weight, make a bigger difference than 2lb of body weight. Also worth noting a 29er will require more anti squat than a 26 to get the same pedalling response, further increasing the Orange's suspension advantage.

No one has mentioned spoke count yet. I usually find more spokes = less power lost.

I've spent ages looking for answers on this sort of thing. Most recently when it turned out my new lighter and shorter travel XC bike wasn't faster at anything than my trail bike. Thought I must be imagining it at first until I rode them round the block one after the other. Sure enough the trail bike pulled like a Saturn V by comparison.

My fastest lap of Whinlatter North was on a 26" HT SS with 650ish bars.

I've been close but never beat that time.

I could analyze bikes but realistically it's me- 2 kids and life priority shift has led to a less quick version.

I’m pretty confident that the old Five climbed faster than the FlareMax, I’m just not sure why.

How much older are you? 🙂

I just checked my times on a local climb, 4.7m and 1253ft which I've done 22 times (on this route).

Rank Date Time Bike
1 2 Aug 2015 46:23 Cube Stereo
2 10 Oct 2012 47:00 456Ti
3 24 Nov 2019 47:07 Flaremax
4 8 Mar 2013 47:55 456Ti
5 22 Dec 2020 48:17 Flaremax

Looks like it's the rider as my 456Ti weighed about 10lbs less than my Flaremax and while age is an issue, I've always been pretty fit and the 5th fastest was this week.

I climbed my banshee rune v3 faster than my 125mm norco optic to Ben Cleuch. Pretty stumped. Maybe all the food!

Could a slacker head angle be a contributory factor? And possibly an unsuitable fork offset for the slack angle, ie one that does not minimise the flop.

I've found rigid bikes with slack HAs need more concentration on a climb because the steering tends to flop more.

Longer chainstays allow a more front biased weight distribution to keep the wheel on the ground, but often the bike then feels less nimble, so steering correction when flopping becomes an issue.

Could a slacker head angle be a contributory factor?

My Flaremax has a -2 degree headset in, so maybe not.

Thanks for the numbers @intheborders I've seen a few people online praising the climbing of the FlareMax but that's the first set of numbers I've seen to back it up.

At 56 I can't rule out the inexorable march of the grim reaper, but with lockdown I've done more riding this year (time, distance and elevation) than ever and have bagged some PRs on the gravel bike, so it doesn't look as though the fitness is falling off much just yet. Maybe I've lost the ability to grind out 20 minute seated climbs or something although it could just be something in the way I've got the bike set up.

Cranks the same length for both bikes?

I think you’ve underestimated just how good a bike the 5 was. And I’m pretty sure that it all comes down to a lighter bike with lighter wheels climbing faster than a heavier bike with heavier wheels. Conversely the heavier wheels should help carry momentum on the descents.

I have a 35lb 2012 Alpine 160 (with a -1.5 headset, offset bushes and a coil CCDB) and it was a bloody brilliant climber (better descender) compared to a lot of my friends bikes with fancier suspension.

I think that that generation of 5 was one of the best bikes around, a good blend of weight, flex/stiffness and responsiveness under power.

I don't think you'll ever get to the bottom of this without having both bikes back to back and a known collection of analytical collection devices to tell you what your body is doing.

Power meter swapped between bikes, same heart rate strap / device and measure from there.

If you can't do this, you have no way of knowing what your working with as a base line and will just waste hour after hour swapping bits out and coming to no real conclusions.

I too have heard good things about the Flaremax and climbing. It's now on my shortlist, hampered slightly by being out of stock.

It's a heavy lump though for it's travel.

I'm currently on a very elderly 2009 Turner Flux with DW link suspension. I have a sneaking suspicion all bikes on my want list might be a backwards step in comparison to that when it comes to climbing. But descenting on it is a lottery and a I fancy bigger wheels to roll over lumpy bits so I guess a compromise worth making.

Also the Ti456 was an utterly shite climber. The only thing that bike did right was descending. I always felt like I was perched on it and only when hanging off the back of it did it feel truly right.

It’s a heavy lump though for it’s travel.

Less than a kg more than the Spesh Camber Evo Carbon it replaced (swapped parts over), and about 6" longer 🙂

An e bike is the best climber by far

Just wanted to put this one to bed. I changed the RockRazor/Magic Mary tyres for a set of older Racing Ralph/Nobby Nic tyres (snakeskin/pacestar) that were in the shed and managed a new PR on an ~23 minute climb (700' at an average of 7.5% with a few steep sections). I took nearly a minute off the time I'd set on a Smuggler back in 2016. So, I think I've shown (at least to my own satisfaction) that the FlareMax can climb as well as any other bike I've owned, it just needs the right tyres.

Part of the issue was me specking a tyre that was more aggressive than I needed and part was due to Schwalbe making their newer tyres a fair bit heavier. The old snakeskin casing suited my mincing very well. I hardly ever punctured and could probably have used the liteskin version without too much issue. But plenty of people did puncture and I guess Schwalbe got fed up with being labelled as fragile. So now, even the SuperGround, which sounds as though it should be the XC carcass tends to be heavier than the old snakeskin. I guess this is a trend that will only continue as more and more people decide that cycling can be improved by bolting an engine to their pushbike.

29 is fastest uphill for me in a specific set of circumstances - relatively untechnical, not particularly steep climbing. As soon as it steepens up, I find I'm putting in a bit more effort to overcome wheel decceleration between each pedal stroke compared with my 27.5 bike. I've probably got a slow cadence compared to quite a few riders, and I guess that amplifies the effect.

On one steep grind of a climb I do fairly regularly, I find it easier on 32-46 on my 27.5 (with slower tyres) than 32-51 on my 29 even though the gear calculator suggests it should be the other way around.

I guess this is a trend that will only continue as more and more people decide that cycling can be improved by bolting an engine to their pushbike.

Hopefully XC racing will still remain a thing, with appropriate tyres. I would therefore expect everything from there on up to full DH tyres to exist. Unfortunately in ever growing numbers of variants, sub niches, and baffling naming conventions.

I find I’m putting in a bit more effort to overcome wheel decceleration between each pedal stroke compared with my 27.5 bike.

You're imagining this. It's not a real thing.

https://crosscountrycycle.wordpress.com/2016/11/25/equal-and-opposite/

^that does assume that you are putting out your maximum power and are being somehow hindered in applying it to the bike/ground, much like the "clipless pedals and pull up on the backstroke for added powaaar" argument. Which I'm going to assume most of us non pro racers do not do on an extended basis, such as the long climb in the OP

There's a lot to be said for being over-tyred (wasn't there a thread on that recently?) you'd be surprised what you can get away with grip/durability wise. The thing with a lot of modern bikes is the geometry allows riders to just plough through things, but that's not always the best way and tyres/rims take the brunt of the abuse. Be a bit more selective with your lines and not just rely on the geometry to get you through it and lighter, faster tyres might become more useable and make climbing less of a chore. Same can be said of enduro bikes for a lot of folks, but that's a whole different debate! Does make me wonder though if the riders who have sold their enduro bike to get an ebike or one to go along side it would have done so had they actually ridden a more appropriate, lighter, shorter travel bike rather than lug a 35lb+ beast around a lap of trail centre...

You’re imagining this. It’s not a real thing.

Stop gaslighting me! I'm not going mad!

Anyhow, I thought that was the key supposed difference between bigger/smaller wheelsizes? Bigger is harder to accelerate, but holds speed better once turning? My perception was that, once it gets steep enough, it's harder on the 29, despite being a lighter bike, with an easier gear and tyres with lower rolling resistance.

My old 26" alloy hardtail on fatter tyres and less suspension seems a much more capable climber that my newer steel, semi-slack angled, longer travel 27.5" HT.

I reckon it's just down to my CoG being in a better place on the 26". Also, As it is a smaller bike, relatively speaking, I can move around more to get my weight in the right place for traction when things get a bit technical.

Bigger is harder to accelerate, but holds speed better once turning?

The difference in a steady climb is negligible. Basically, a wheel rim and tyre count for twice as much when you are accelerating because you need to spin it faster and also move it forward. However, the difference between a 29" and 27" tyre and rim is not that huge. Unless you are climbing at a walking pace and pretty much coming to rest between pedal strokes, your speed is not varying by as much as you seem to assume so you are not accelerating the wheel very much. The tyre's rolling resistance will make a much bigger difference than the difference in weight between 27" and 29" versions of the same rim and tyre.

My incredibly unscientific 'test' recently, showed that a 26" wheeled hardtail from 10 years ago or more, was quickest up most climbs, although a 29" lightweight carbon framed bike rolled better over roots and bumps, and a 27.5" full suspension 'trail' type bike was an absolute pig. I also know that I was a fair bit quicker say 20, 30 years ago. Thus proving that the bikes back then were better at climbing. 😀

The whole idea about 'rotating weight' is a bit of a cycling myth. On road bikes, there's basically no difference between heavy vs lightweight wheels on a weight-compensated frame.

https://www.swissside.com/blogs/news/aero-vs-weight?locale=de

I guess MTBs are slightly different, as depending on the terrain, the wheels may be forced to accelerate / decelerate more often than on a steady road grind with constant wheel RPM.

Interesting about the tyres though. I'm usually running heavy carcass Magic Marys (which are great on the descents), but I ended up doing a ride on far lighter Nobby Nics which felt way quicker. Perhaps the pendulum needs to swing back to slighter lighter tyres.

Back when 26 x 1.95 tyres were normal, you were looking at 400 g to 500 g for an XC tyre. A fat 29" DH tyre is going to weigh two or three times as much, plus the rims will be heavier, so you're adding a couple of kilos of rotating mass, along with very draggy tyres that are optimized for grip with no concern for rolling resistance. In that case, the heavy tyre will feel very sluggish to pedal but stable at high speed because the wheels have a strong gyroscopic effect.

Back when 26 x 1.95 tyres were normal, you were looking at 400 g to 500 g for an XC tyre. A fat 29″ DH tyre is going to weigh two or three times as much, plus the rims will be heavier, so you’re adding a couple of kilos of rotating mass, along with very draggy tyres that are optimized for grip with no concern for rolling resistance. In that case, the heavy tyre will feel very sluggish to pedal but stable at high speed because the wheels have a strong gyroscopic effect.

This is a really good, concise analysis. Thanks.

Interesting about the tyres though. I’m usually running heavy carcass Magic Marys (which are great on the descents), but I ended up doing a ride on far lighter Nobby Nics which felt way quicker. Perhaps the pendulum needs to swing back to slighter lighter tyres.

It sounds right but I'll refer back to my post from the top of the page.
#2 would've been on a 1450g wheelset & Ardent/Larsen combo - all in about 3kg
#5 was on a 1900g wheelset & Michelin Enduro 2.4's - all in about 4.1kg

Rank Date Time Bike
1 2 Aug 2015 46:23 Cube Stereo
2 10 Oct 2012 47:00 456Ti
3 24 Nov 2019 47:07 Flaremax
4 8 Mar 2013 47:55 456Ti
5 22 Dec 2020 48:17 Flaremax

Geometry? Particularly CS length.