Bikepacking chainri...
 

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Bikepacking chainring size question.

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I'm currently running a 32t oval chain ring on my bike with a GX Eagle 10-50 tooth cassette.

I'm finding it too tall gearing for a full lade bike when the trail gets steeper, I'm either having to get off and push, which is unpleasant, or I'm killing my legs which has consequences the next day.

Yes, rule 5 applies, but the drivetrain is wearing out, and I'm planning a 3 week trip next year, so I'd like shorter gearing.

I'm wondering whether to go as low as 28t on the front? It's a hardtail so it won't hit the chainstays or anything like that.


 
Posted : 09/09/2024 12:42 pm
branes and branes reacted
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Thats a fairly low first gear you have already.  Mines similar.  I find I can ride that low first gear at 4 mph with a normal cadence or down to 2.5 mph with a slow cadence.  I am not sure I could actually ride much slower without falling off

Would you actually be able to ride in a lower first gear?  Maybe bung a 28 on  now on the same drivetrain to see?

that being said I am of the opinion that for touring / backpacking low gears are good.


 
Posted : 09/09/2024 12:57 pm
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That was why I'm asking the question @tjagain.

don't  think that the 30t front chainring would be too small, but I do wonder if the 28t would be, so that the bike wouldn't be rideable.


 
Posted : 09/09/2024 1:08 pm
trail_rat and trail_rat reacted
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If it's too high, put a small chainring on.  End.


 
Posted : 09/09/2024 1:09 pm
phil5556, fasthaggis, fasthaggis and 1 people reacted
 jfab
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With the exception of a steep road climb I'd be surprised if there's much you could use a 28/50 lowest gear on without it being so steep you just won't have traction anyway especially on a hardtail.

No harm in trying, especially if you're expecting to be covering some long draggy non-technical climbs on your trip but I think you'd have so little momentum at that speed that what you gain in ease of pedalling you'll lose in actually being able to clear any trail features and end up off the bike anyway. I borrowed a full-suspension with a 28T chainring and 50T cassette and you could ease yourself up and over some really chunky climbs due to the traction but the slightest slip of the rear wheel under power and you were off the bike and not getting going again due to your speed being so low.


 
Posted : 09/09/2024 1:10 pm
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Chuck your possible specs into a gear calculator.  I reckon your 10*50 is roughly the same as my lowest gear on a 3*9 tourer. I still walk some hills.

Personally I feel any more than one gear lower would be too slow to balance. I can ride my current gear at around 4mph.

I would go with a 30t. One gear lower and still around 82inches top end.

https://www.sheldonbrown.com/gear-calc.html


 
Posted : 09/09/2024 1:23 pm
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Have a  fiddle with this? - my security did not like the link but its fine BTW

https://sheldonbrown.com/gear-calc.html

I think in your position I would get a cheap 28 ring and try it


 
Posted : 09/09/2024 1:24 pm
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My (very approximate) gear calculating spreadsheet makes 28x50 on 29x2.1 tyre to be about 16 inch gear (wheel equivalent diameter).

This is more or less the same as the 22x36 gear on my old bike with 26x2.1 tyres that I use for commuting and general stuff. Although very low I find that gear useful for things like riding up a steep hill (1 in 4) with full panniers on the occasion that I am keen and have the time to do a full Aldi run with large panniers and a front bag.

It is a ridable gear if you like to spin pedals. If you try to stand and grind in that low it can result in either wheelspin or front wheel lift.

For me a gear that low sounds perfect. YMMV


 
Posted : 09/09/2024 1:24 pm
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im not sure about the naysaying

if its a 29er it would be pretty standard to run a 30t anyway imho,  there's been times on my 29er hardtail when i had wished for a 28t and that's not a backpacking bike, so yes, 28t it and find out


 
Posted : 09/09/2024 1:27 pm
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Sorry, yes it is a 29er, running 2.3 inch tyres.


 
Posted : 09/09/2024 1:34 pm
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I run 30t on my enduro bike. Makes steep fireroad climbs easier.

I even tried 28t which meant I could pedal steeper climbs without having to get off. But the smaller cog negatively affected suspension performance and increased anti squat so I switched back. But that's not an issue on a hard tail.

That 28t ring is still on my 'dad bike' which makes riding up steep hills laden with a toddler on a shotgun seat much easier. Similar to touring/bike packing I suppose.

Yes, you're going about the same speed as getting off and pushing, but it's more satisfying staying on the bike when on a...you know...bike ride.


 
Posted : 09/09/2024 1:38 pm
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I fitted a 30t on  front of my hardtail for bike packing trip a year and a half ago and it's stayed on since.

11-46 cassette

I've not missed the higher gear much. I was very happy to have a lower gear on the monster hills


 
Posted : 09/09/2024 2:26 pm
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Pretty sure my HT was 30t from the shop, so 28t is only half a gear lower than the existing setup. I'd happily swap it.

After years riding a 2:1 single speed I'm not sure there's really a huge amount of value in any gear much above that anyway.  It's enough on the flat, and descents are inherently over and done with quickly so other than a few frustrating moments they're not really worth gearing for. 28-10 would still have you pedaling on anything other than a road descent.

Probably better for chain life too, most people gear so that they use the lowest on any significant climbing.  Whereas what you really want is to be closer to the middle of the cassette most of the time, and most of the time is climbing because it's slow!


 
Posted : 09/09/2024 2:45 pm
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I run 32 with an 11-51 on my Camino. When I wear it out I'll probably go for a 30T chainring as occasionally when I'm tired I click for that extra low gear and find it's not there. I'd consider a 28 too but not sure I'd need it.

I only spin out on tarmac downhill which I don't ride much but have a 38T ring I can put on for that if needed.

IMG-0616


 
Posted : 09/09/2024 5:01 pm
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32x50 is pretty low, I’d think any lower than that and you’d be quicker walking


 
Posted : 09/09/2024 5:05 pm
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I have 34/24 x 11-42 on my Fatbike, which is often used for bikepacking. Of course 4.5" tyres help with traction too.


 
Posted : 09/09/2024 6:14 pm
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I am no olympian and want to ride up hill when bike packing just like you . If its down hill bike packing there is no need to pedal.

I therefore run a 26 on the fatty and 28 on the 29er, both 11-50 cassettes.

The only down side is long fast tarmac sections but just chill and embrace the view. Your mates who were pushing up that last hill just have to wait.


 
Posted : 09/09/2024 7:12 pm
phil5556 and phil5556 reacted
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@MadBillMcMad and do you find that the bike is rideable in the lowest gear, albeit slowly?


 
Posted : 09/09/2024 9:04 pm
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32x50 is 16.2 gear inches. My lowest is 16.6, so not much different. The bike is definitely rideable.


 
Posted : 09/09/2024 9:36 pm
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32×50 is pretty low, I’d think any lower than that and you’d be quicker walking

I’d rather ride at walking pace than get off and push.

My mountain bikes have 30 x 51 & 52 - both are perfectly rideable in their lowest gears.


 
Posted : 09/09/2024 9:40 pm
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Depends if you are happy sacrificing it at the top end - it’s why 1 x is still a significant compromise for lots of riding (IMO).

Crazy to think that a few years ago, 44t front rings were common on a triple, 48t weren’t unusual.


 
Posted : 09/09/2024 10:04 pm

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