[Nexus 8] Riding without left hand-side dust cap?
03-01-21, 05:51 AM
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[SOLVED] [Nexus 8] Riding without left hand-side dust cap?
Hello,
To stick a Shimano Nexus 8 gear hub into a Brompton (OLD 112mm), I'm thinking of removing the left hand-side "dust cap unit" and shave 12mm (132mm → 120mm; 3.68mm could be further saved by replacing the LHS lock nut with its RHS, thinner alter ego, and achieve an OLD of 116.32mm).
Do you think it's reasonable to ride without it in a moderately rainy region (Western Europe), even if it means squirting fresh grease on the bearing balls more often?
If not, is some kind of cap available?
Thank you.
To stick a Shimano Nexus 8 gear hub into a Brompton (OLD 112mm), I'm thinking of removing the left hand-side "dust cap unit" and shave 12mm (132mm → 120mm; 3.68mm could be further saved by replacing the LHS lock nut with its RHS, thinner alter ego, and achieve an OLD of 116.32mm).
Do you think it's reasonable to ride without it in a moderately rainy region (Western Europe), even if it means squirting fresh grease on the bearing balls more often?
If not, is some kind of cap available?
Thank you.
Last edited by Winfried; 03-01-21 at 12:54 PM.
03-01-21, 05:56 AM
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I expect that the dust cap was put there for a good reason.
03-01-21, 06:05 AM
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The dust cap does not only protect the hub from rain. It also protects it from DUST.
If dust gets in, it mixes with oil/grease and starts sanding parts down when they turn. It doesn't seem like a good idea to me.
If dust gets in, it mixes with oil/grease and starts sanding parts down when they turn. It doesn't seem like a good idea to me.
03-01-21, 06:33 AM
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Or, if you are or happen to know someone with decent engineering skills, you could try devising some kind of alternative.
For example, many bikes from the cheaper end of the market had pressed aluminium dust shields on either end of the BB as the sole protection against the ingress of dust and/or water, as do the coaster brake hubs from Velosteel.
I have never examined a Nexus in detail but, heh ho, life is short and engineering the final front door.
For example, many bikes from the cheaper end of the market had pressed aluminium dust shields on either end of the BB as the sole protection against the ingress of dust and/or water, as do the coaster brake hubs from Velosteel.
I have never examined a Nexus in detail but, heh ho, life is short and engineering the final front door.
03-01-21, 11:44 AM
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However, the BWR from Sturmey-Archer that powers the six-speed Brompton has no dust cap, just a lock nut + cone:
03-01-21, 11:47 AM
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Another thing that must be addressed: After removing those parts on the left side, the hub will be moved to the left, so when cold-setting the frame, it should be pulled asymetrically so the right stay lies further to the right.
03-01-21, 12:54 PM
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Got a reply from gear hubs expert Aaron Goss: "It is fine. We have done it. Yes grease more often."
03-01-21, 09:41 PM
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I think it's not really a dustcap, but it's there to cover the splines if you don't use a roller brake.
03-02-21, 01:18 PM
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It's how Shimano calls it: "Left Hand Dust Cap Unit (Y-34R 98100).
Regardless, it then opens a new issue: Using that trick, the rim would now be way too far to the left :-/
Regardless, it then opens a new issue: Using that trick, the rim would now be way too far to the left :-/
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