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Rearranging cassette for greater climbing efficiency


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So I'm training to have a crack at my nemesis mountain. And I'm currently sick with a cold so have moved onto plotting and planning ways to go up faster on the watts I will have.

One of those ways is the thought of rearranging the cassette so that the climbing gears are closer to the middle, by moving some of the small gears to the back of the cassette, behind the climbing gears. This should in theory offer a straighter chain line.

Anyone done it? Will it work? 

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Not done it but I guess it would work. I guess a 12-28 cassette may become a: 12, 14, 17, 21, 23, 25, 28, 13, 15, 16, 19. Possibly need to adjust the travel screws on  your rear derailleur to ensure you didn't shift off/past the climbing gears in the middle to one of the smaller gears now at the back/inside of the cassette, as it wont be able to come back. Is your chain line that 'not straight' that its an issue when in your small chain ring to your climbing gears (25/28?). Dont some cassettes come with the last three/four gears (21-28?) on the one spline? Might need to have this block in the middle. Interesting thoought, curious to hear others thoughts on it.

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Derailleurs move in a way that releases to go down, and it's pulled to move up (ok, electronic is different, but I guess the principal still applies).  Releasing works to go down as it's dropping onto a smaller cog each time.  I wonder if that would still work when dropping onto a larger cog?

I wonder just how many watts you are losing if you're in the small chainring and the top half of the cassette?  Not a lot of cross chaining going on there?  

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Thanks, and it's not a new idea as I'm sure gcn did it for one of their challenges, and the recent everesting record was set with some spacers behind the cassette to move the required gears into the centre, while removing others entirely 

If I get time I'll pull apart a cassette on my wheels and give it a go.

I am terrified I'll accidentally shift past the granny gear ha ha. Limiting screw might sort that out.

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Just now, goughy said:

Derailleurs move in a way that releases to go down, and it's pulled to move up (ok, electronic is different, but I guess the principal still applies).  Releasing works to go down as it's dropping onto a smaller cog each time.  I wonder if that would still work when dropping onto a larger cog?

I wonder just how many watts you are losing if you're in the small chainring and the top half of the cassette?  Not a lot of cross chaining going on there?  

Yes, I'm also not sure how much cross chaining we are talking about, it watts saved, but it might be fun anyway 😛

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No point unless you plan on setting a world record of some kind and you're already north of 500 watts for the climb (power loss will scale linearly with power output so more you're capable of, the more it becomes critical)

The watts saved would probably be less than the watts saved if you left the biddon at home (for mere mortals at least)

A chain with a decent lube wont lose enough power to be worth the risk IMO

And the number of people I see riding around on the big ring out front while also using the largest cog out back probably proves my point

Having said that, I'm sure someone like Adam from Zero Friction Cycling or Alex Simmons could give you exact numbers

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8 minutes ago, Mr Tinman said:

No point unless you plan on setting a world record of some kind and you're already north of 500 watts for the climb (power loss will scale linearly with power output so more you're capable of, the more it becomes critical)

The watts saved would probably be less than the watts saved if you left the biddon at home (for mere mortals at least)

A chain with a decent lube wont lose enough power to be worth the risk IMO

And the number of people I see riding around on the big ring out front while also using the largest cog out back probably proves my point

Having said that, I'm sure someone like Adam from Zero Friction Cycling or Alex Simmons could give you exact numbers

I'm working on the biddon. Losing the cages and might just take a couple small fluids in the back pocket or get someone to give me fluid half way or something. I'm not going to set records but with no events for me this year I'm looking for ways to achieve some goals and have fun.

I'd say no biddon but I'm aiming for a 1hr climb time and I've read the fluid needs will outweigh the weight penalty, but I'm not a thirsty one, so some compromise is probably in order. 

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Seems I was right

https://www.ceramicspeed.com/media/3502/cross-chaining-and-ring-size-report.pdf

Difference between less than optimal chain line isnt that much..."

While the data shows a savings of 0.74 watts by staying out of the big ring and biggest cog combination at lower final gear ratios"

Drag is "far" higher in the small/small combination....and it's still only 2.86 watts

A dirty chain will cost a lot more than that.

I think I read somewhere (Zero Friction Cycling possibly) that a filthy chain can cost as much as 20 watts 

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Posted (edited)
24 minutes ago, Mr Tinman said:

Seems I was right

https://www.ceramicspeed.com/media/3502/cross-chaining-and-ring-size-report.pdf

Difference between less than optimal chain line isnt that much..."

While the data shows a savings of 0.74 watts by staying out of the big ring and biggest cog combination at lower final gear ratios"

Drag is "far" higher in the small/small combination....and it's still only 2.86 watts

A dirty chain will cost a lot more than that.

I think I read somewhere (Zero Friction Cycling possibly) that a filthy chain can cost as much as 20 watts 

Interesting, thanks! Having a casual read it would seem the best setup in theory would be an aligned big chainring and large cog combination if the ratio was available. Not sure that would be the case for me. 53/32 hmm. Need those oversized jockey wheels too ha ha. Good to see the numbers aren't very big in terms of savings, somewhat expected though. You could spend a lot of money chasing a few watts.

I will of course thoroughly clean my drivetrain and lube before attempt. I'd wax if I had the equipment and it wasn't such a pain and expense 😛

Edited by dazaau
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Posted (edited)
1 hour ago, Mr Tinman said:

Seems I was right

https://www.ceramicspeed.com/media/3502/cross-chaining-and-ring-size-report.pdf

Difference between less than optimal chain line isnt that much..."

While the data shows a savings of 0.74 watts by staying out of the big ring and biggest cog combination at lower final gear ratios"

Drag is "far" higher in the small/small combination....and it's still only 2.86 watts

A dirty chain will cost a lot more than that.

I think I read somewhere (Zero Friction Cycling possibly) that a filthy chain can cost as much as 20 watts 

On chain cleaning, I looked at some stuff by zero friction and my lube is efficient enough, but I'm unsure of the recommended cleaning process. It appears I should practically strip the chain? Is that right. I usually just spray degrease, wipe down and apply lube but I'm open to soaking in terps for the heck of it if it's useful. But I don't want to screw it up!

Edited by dazaau
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Follow the recommendations from Zero friction

I use a gatorade bottle (or anything with a wide mouth makes it easier to get the chain in), drop in chain , half fill with turps, soak for 10-15 minutes (but no more as it can lead to hydrogen embrittlement) shake the shit out of it for 30 s, dispose of turps, re-fill, reshake (wont need to soak).

If its really bad, you may need to repeat once more

Than drain and fill with metho to clean off turps. Repeat and dry chain (otherwise you could get some corrosion)

Apply lube of choice

 

TL;DR - Clean with 2-3 shake sessions of turps followed by 2 shake sessions of metho, dry and lube

Edited by Mr Tinman
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2 minutes ago, Mr Tinman said:

Follow the recommendations from Zero friction

I use a gatorade bottle (or anything with a wide mouth makes it easier to get the chain in), drop in chain , half fill with turps, soak for 10-15 minutes (but no more as it can lead to hydrogen embrittlement) shake the shit out of it for 30 s, dispose of turps, re-fill, reshake (wont need to soak).

If its really bad, you may need to repeat once more

Than drain and fill with metho to clean off turps. Repeat and dry chain (otherwise you could get some corrosion)

Apply lube of choice

 

TL;DR - Clean with 2-3 shake sessions of turps followed by 2 shake sessions of metho, dry and lube

Awesome, that will be fun 😛

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So for those interested I've started the video at the relevant section. Unfortunately the gains for me wouldn't be nearly as big (claimed up to 5w, but I think that is a bit exaggerated as per the link from Tinman) unless I ride the big ring, but with gradients up to 11% and an average of 6.4% I don't think that's going to happen with a max 32 tooth cog and a desired cadence of 85-90. 

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Get lean & ride the same climb alot. Get used to wind, using the camber of the corners & knowing when to push & when to hold steady pace. Pacing is the key. 

I have been trying to give Norton Summit in SA a crack. I'm chasing a sub 16min time. 

I will get it. 

My best effort was on the 24 Feb as you can see my watts was higher but unfortunately the wind wasn't in my fav. Never head up hill with a full bidon. 

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58 minutes ago, Bored@work said:

Get lean & ride the same climb alot. Get used to wind, using the camber of the corners & knowing when to push & when to hold steady pace. Pacing is the key. 

I have been trying to give Norton Summit in SA a crack. I'm chasing a sub 16min time. 

I will get it. 

My best effort was on the 24 Feb as you can see my watts was higher but unfortunately the wind wasn't in my fav. Never head up hill with a full bidon. 

I'm sure you will! That's close. I'm 11 seconds off a sub 17 1/20 here in Melbourne so I can visualise the gap ha ha. Though my obsession is with this mountain. Interesting to see how the power put out does not correlate all that close to the times. 

That's all good advice and I've got this app called WINDY on my phone to make sure that when I really go for it there is little to no wind. There is an open section near the top and when it's windy it not only slows you down but it totally does your head in too. 

Edited by dazaau
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6 hours ago, Bored@work said:

Get lean & ride the same climb alot. Get used to wind, using the camber of the corners & knowing when to push & when to hold steady pace. Pacing is the key. 

I have been trying to give Norton Summit in SA a crack. I'm chasing a sub 16min time. 

I will get it. 

My best effort was on the 24 Feb as you can see my watts was higher but unfortunately the wind wasn't in my fav. Never head up hill with a full bidon. 

Sure that's in your best interests?

That load of smegma (DR) will call you a cheat and say you're doping

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On 06/04/2021 at 5:10 PM, dazaau said:

Rearranging cassette for greater climbing efficiency...

Anyone done it? Will it work? 

The only way changing a 'cassette' could make me climb faster is if the cassette played Skyhooks, Hunters & Collectors or Cold Chisel etc.

Providing it's not too warm, drink the hour's worth of fluid before starting your ride and put that extra weight on your pedals.

Pump up your tyres, clean your spokes well, and just give your chain a big dose of WD40 before starting.

That will help you much more than rearranging your gearing.  Give it a crack!

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2 minutes ago, Go Easy said:

The only way changing a 'cassette' could make me climb faster is if the cassette played Skyhooks, Hunters & Collectors or Cold Chisel etc.

Providing it's not too warm, drink the hour's worth of fluid before starting your ride and put that extra weight on your pedals.

Pump up your tyres, clean your spokes well, and just give your chain a big dose of WD40 before starting.

That will help you much more than rearranging your gearing.  Give it a crack!

I'm still sick and stuck at home off the bike. It's killing me. What else can I do but think of crazy ways to go faster lol.

 

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Vitamin C and Zinc...

As Bored suggests when you're fit again climb it lots, learn milestone markers along the way (eg a certain tree in 20 minutes, or a certain light post in 30 minutes etc) that you can use to see if you're on or close to a PB.  If you're not feeling it, and are not on your PB pace anyway, just enjoy your 'training' ride.  If you get to your markers, particularly the later ones, on or close to your PB time then go for it!

I guess you could do the same thing using your watts or average speed, but during most rides (if you're going hard enough) you tend to alternate between feeling good and feeling gone, so don't let the figures put you off if you can't maintain them along the way.  Good luck with it!

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15 minutes ago, Bored@work said:

Become an expert on judging the wind direction required to get that PB. I have left work meetings because the wind was in the right direction to get a PB.

Closest I have ever come to a strava KOM (top 10) was on a flat 1km segment when there was a howling tail wind. Only rode to that segment to beat a mates time, and then went home; that's not cheating is it?

Bah, I just checked and I have dropped out of the top 10.

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I once held several sprint KOM's

I was far fitter (and thinner) at the time, but mostly because I made them 😂

Having said that, Im only 2-3 seconds out of the top ten on several other near me and I haven't really had a red hot go at either yet....so there is still hope

 

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