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40/42 tooth Rear XT...
 

[Closed] 40/42 tooth Rear XT cassette 'bodge'

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[#6091658]

Thought I'd share this with the STW massif...Got a hope T rex 40 tooth last week and didnt really want to take the 17 tooth cog out and have the split in ratios so I had a mess around and have come up with a fix that allows you to take off the 11 tooth bottom cog and still use the original lockring. I used a plastic frame spacer from a shimano external bottom bracket and cut a small section out of it and then forced it into the small groove on the 13tooth cog (which was originally gear number 9 of 10). This allows the lockring to sit against it and tighten into the freehub body. The spacer is sat on the metal rim so wont push through. Just been out and done 50 miles off road around Wharncliffe and surrounding area and its been fine. I am going to put a bit of nut lock on the lockring as it doesnt have the serrated edge of the 11 tooth to bite into( i torqued it up to recommended). Running 1 x 10 with a Wolf Tooth thick thin on front and it didnt miss a beat thru some crappy condtions. Sorry for long winded explanation!!!.


 
Posted : 04/04/2014 3:04 pm
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Braver man than me. What could possibly go wrong? ๐Ÿ™‚


 
Posted : 04/04/2014 3:07 pm
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As far I can see absolutely nothing!!!


 
Posted : 04/04/2014 3:12 pm
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Sounds like an interesting idea. I dropped the 15 on mine, but it's a bit od a jump down to the 13. I rarely use the 11, so might give this a try.


 
Posted : 04/04/2014 3:14 pm
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a 34t chainring with 13/40 is comparable to running a 30t chainring and 11/36

so just change yer front ring shirley?

34:13 = 69.1"
34:40 = 22.4"

30:11 = 72"
30:36 = 22"


 
Posted : 04/04/2014 3:20 pm
 D0NK
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hmm 11 to 13 looses* you about 3mph from your top speed with a 32 front, not sure I'd want to give that up but may be worth a try I guess.

30:11 = 72"
30:36 = 22"
quick google, nope not quite low enough range, would have been cheaper than 32x11-36 + 42. Ah well.

*is cougar around?


 
Posted : 04/04/2014 3:26 pm
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This doesn't seem to make much sense! 13:40 is a smaller spread of ratios than 11:36 - and the cassette is heavier and more expensive.


 
Posted : 04/04/2014 5:28 pm
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I used individual sprockets to get ratios I liked, the big jump is on the shift from 4th to 5th @ 20t- 26t. on a 9 speed 11-40


 
Posted : 04/04/2014 5:45 pm
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Blimey, there is a worrying lack of basic maths knowhow out there... ๐Ÿ˜ฏ
11 to 13 is a 22% loss off the top. 36 to 42 is a 17% gain at the bottom. All could be achieved with less cost and shifting issues by running a smaller chainring...


 
Posted : 04/04/2014 5:59 pm
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LOL, I wondered when this was going to surface again as it did when the 40/42 rings first appeared! Congratulations on making a smaller range cassette than you started with.


 
Posted : 04/04/2014 7:36 pm
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Seems reasonable enough if you can't go any smaller up front - don't think you can got lower that 30t on most 104BCD cranksets


 
Posted : 04/04/2014 8:04 pm
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Seems reasonable enough if you can't go any smaller up front - don't think you can got lower that 30t on most 104BCD cranksets

Why not just use the inner ring position of a double crankset?


 
Posted : 04/04/2014 8:05 pm
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cos I don't have a front mech or shifter. Anyway, I'm planning to ditch the 17T, not the 11T, so I don't know why I keep banging on about it ๐Ÿ™‚


 
Posted : 04/04/2014 9:12 pm
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My point was that you can run 1x10 using a middle ring of a 3x, the outer ring of a 2x or the inner ring of a 2x - which allows you to run a huge range of chainring sizes. But I see no point in paying for a range extender big sprocket if you then remove the 11t sprocket instead of taking a mid-sized sprocket out!


 
Posted : 04/04/2014 9:35 pm