Author Topic: Thorn Black 165mm 104/64 Triple crankset mark 2  (Read 3783 times)

Teaboy

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Thorn Black 165mm 104/64 Triple crankset mark 2
« on: July 02, 2016, 05:12:14 pm »
https://www.sjscycles.co.uk/cranks/150-thorn-10464-pcd-triple-crankset-mk2-black/

Thorn part No. 31813L165

fitted with Black Thorn 3/32" 46T reversible ring  (Thorn part No. 11054S46)

plus

Black Thorn 3/32" 46T  34T reversible ring (Thorn part No 11054S34)

All new Oct 2015.  800 miles on road use.

£40.00 plus postage.
« Last Edit: July 02, 2016, 05:14:55 pm by Teaboy »

silverdorking

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Re: Thorn Black 165mm 104/64 Triple crankset mark 2
« Reply #1 on: July 03, 2016, 08:20:49 pm »
Hi, sorry for my ignorance but would these work, alignment wise with rhollof equipped Bike?

JimK

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Re: Thorn Black 165mm 104/64 Triple crankset mark 2
« Reply #2 on: July 03, 2016, 08:29:22 pm »
there are some clues on the SJS description: "110mm bracket required to get a 54mm chainline on middle ring, 107mm can be used if only using a single ring in the outer position."

I think 54 mm is the old Rohloff chainline, with the threaded sprockets. The new sprockets bump it up to 57mm, as I recall. I think a 1mm increase in chainline needs a 2 mm increase in bracket, because the bracket is measured full width while the chainline is measured half-width, i.e. center to edge.

I have never actually worked with this stuff so I hope those with real experience will chip in and correct me!

Donerol

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Re: Thorn Black 165mm 104/64 Triple crankset mark 2
« Reply #3 on: July 09, 2016, 10:10:34 pm »
If you put the ring in the outer position instead of the middle you 'gain' 3mm, so it would work with the new sprockets.

silverdorking

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Re: Thorn Black 165mm 104/64 Triple crankset mark 2
« Reply #4 on: July 12, 2016, 06:03:05 pm »
Thanks for this helpful advice but it seems that I would need new bottom bracket to accommodate these cranks it seems to make sense to dive out and stay with existing. So thanks all again!