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Middleburn, gearing, and BB help

687 views 17 replies 7 participants last post by  Wish I Were Riding 
#1 ·
I've finally decided to get some Middleburns. I've been riding Sugino XD300's and they've been just fine. However the Middleburns are lighter and I think I deserve nice cranks for my SSing.

Their site says I should use a 113mm BB. Any reason not to go with that recommendation?

As for gearing... I'm not sure what to do. I've been running 36x24 on my 29er, and its just a little too easy. When I get the Middleburns I will be looking to use the Uno ring in either 34 or 32 tooth. How much difference would I feel between 32x21 and 34x22?

Gear chart using Gear Inches
For 29 inch (nominal) tire with 175 mm cranks
With Custom Sizes Cassette

32 34 36
20 46.4 49.3 52.2
21 44.2 47.0 49.7
22 42.2 44.8 47.5
23 40.3 42.9 45.4
24 38.7 41.1 43.5
 
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#4 ·
Wish I Were Riding said:
How much difference would I feel between 32x21 and 34x22?
Almost none. If you are really tuned into your bike, you might just be able to identify them correctly in a blind climb test.

I'd go 34:21, for just under 48 gear inches. That would be equivalent to a 36x22, 'the next gear', so to speak.
 
#7 ·
sunset1123 said:
Almost none. If you are really tuned into your bike, you might just be able to identify them correctly in a blind climb test.

I'd go 34:21, for just under 48 gear inches. That would be equivalent to a 36x22, 'the next gear', so to speak.
That's interesting. How do you define "the next gear". Maybe 32x20 would be good as well?
 
#12 ·
Wish I Were Riding said:
I know what "chainline" is, I was wondering if 50mm was wide. I don't use freewheels with fixed chainlines.
Paul Components notes that the WORD ended up having a 52mm chainline, and as it was the first purpose-built 135mm-spaced singlespeed freewheel hub, all the Johnny-come-lately hub manufacturers followed suit.

Middleburn notes that other factors may affect the length of the BB spindle you ultimately end up with. Since the components are all interchangeable, it makes sense for them to define a starting point to work from depending on your specific needs.
 
#13 ·
Wish I Were Riding said:
That's interesting. How do you define "the next gear". Maybe 32x20 would be good as well?
'the next gear' ie: on a gearie bike, if you were to shift up once from 36:24, depending on cassette, you would be in a 36:22.

32:20 will be in the same range, within 0.5 gear inches of 36:22 or 34:21. You are looking at an increase in the range of 3 to 3.5 gear inches, which is a good amount to change. I'd favor the 34:21 just because of the greater tooth count.
 
#15 ·
umarth said:
I think I could get behind a 34x21. Kinda depends on how easy you thought 36x24 was.
While I thought the 36x24 felt easier then the 38x24 and 36x22 I've also recently run, I would say to was totally easy. I do think that going to a harder gear will be okay. I like to make all my climbs, but some in my area can be very tough. I think 34x21 sounds pretty good, and I'll probably go this route. I still want to make most of my climbs without walking, but occasionally having to walk can either mean I need to get in better shape or I've got just the right gear. Would you agree?
 
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