It appears I did not sufficiently heed the first rule of disassembling something: carefully observe the order (and side) of where things come from.

Three quick questions:

The image below shows an 8mm locknut and a 5mm locknut.

  1. Is it a general rule that the larger (8mm) nut is from the non-drive side of the axle, and the smaller (5mm) one from the drive side?

two nuts

The image below shows the one, and only one washer that separated a locknut from its cone.

Two nuts and a washer

  1. Is there a general rule regarding whether a single washer would be on the drive side or the non-drive side?

If you can also address the following question, please do, but it may be that it does not have an answer.

Eagle eyes looking at the following image

rear derailleur at rest outside plane of smallest sprocket

can tell that the locknut protrudes too much—so much that the largest sprocket is unreachable by the derailleur.

  1. How much protrusion (how many millimeters) from the plane of the smallest sprocket to the end of the drive-side locknut will tell you that the range of the derailleur may not allow it to reach the largest sprocket?

2 Answers 2


Checking a couple of my bikes, the spacing ranges from "very small" to a couple mm total.

The chain has to clear the frame when in the highest gear - there must be no way for the chain to rub on the frame. Likewise, the cassette itself must also not rub on the frame when turning. And while riding, the frame has some amount of flex so you need to allow for that.

The rim must end up centered in the frame, and to avoid too large a difference in spoke tensions, the cassette should be as far right as it can reasonably go. This also helps with rim brake positioning.

Likewise, the rim should be centered between chainstays and seatstays when the axle is fully seated in the dropouts.

It is not unusual to see a fairly long length of axle with spacers on the left hand side of the wheel to try and balance the spacing.

  • 1
    I see. Makes perfect sense now. Any space left "wasted" on the drive side contributes to an increased imbalance in tension between the spokes on the two sides. Likewise it is desirable for a big nut and a washer to occupy the space on the non-drive side to contribute to the same effect. I wonder if accumulating this kind of knowledge is sufficient in the long run to build a bike from individual components (as a challenge and a labour of love; I know it's not economical).
    – Sam7919
    Commented Sep 11, 2022 at 21:06

At least with 9+ speed hubs the gap between smallest sprocket and frame is – unfortunately – exactly narrow enough to jam the chain in there. In your photo the gap is significantly wider than the chain.

Hub manufacturers really don’t want to waste space between frame and the drive side hub flanges (the many sprockets of modern cassettes take up a lot of space).

Since your wheel is already built, my main goal would be to have the rim in the centerline of the bike/frame and the derailleur able to reach all the sprockets. The hub+nuts should fit nicely between the dropouts without leaving a gap or having to widen the dropout.

On Shimano rear hubs they use the same lock nuts on both sides, I haven’t encountered a rear hub with different thickness lock nuts yet.

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