Track nut sizing

[Vladimir]

So this is a stupid question, I'm sure, but here goes:

What is the usual size of the nuts on nutted axles on bicycles? I bought my on-one pompino fixie 2 years ago, for reference. I'm looking to replace one of the nuts in question.

The wheelset is probably the ALD 30 from planet x:

I've found some retailers who would like to charge around £6 for a couple of wheel nuts with integrated washers, but I don't fancy paying that!

Will these do: http://www.ebay.co.uk/itm/Weldtite-Bike ... 2c900087f5 in a 3/8" size?

[Brucey]

Will these do: http://www.ebay.co.uk/itm/Weldtite-Bike ... 2c900087f5 in a 3/8" size?

No, probably not. There are quite a few thread standards around and you need to be absolutely sure that you have the right one; it would be easy enough to buy the wrong ones and perhaps strip the thread on the axle.

IIRC your hubs might have a 10mm x 26tpi thread, which is one of the less commonplace ones. You can get an idea of the different thread standards available if you look on Sheldon Brown or this page;

http://www.sjscycles.co.uk/wheel-axles-qr-and-nutted-dept654_pg1/#filterkey=brand&brand=WHEELS_MANUFACTURING&page=1

which shows just a few different axles...

cheers

[Vladimir]

ok, thanks Brucey.

How do I determine which one I need, then? If I upload a picture on here, would someone be able to tell?

[Brucey]

you need to confirm the spec with the supplier or to measure them. Measuring is difficult; in particular telling the difference between a 1mm pitch and 26tpi is difficult; the easiest way of doing this is to use a thread pitch gauge or failing that another bolt (like an M6x1) with the same pitch; side by side they should mesh exactly over a length of 25mm or so.

cheers

[Vladimir]

I did get in touch with Planet X.

I think they must have misunderstood my request because the reply was that the thread is 35 x 24F
He did give me the link to the hub: http://www.miche.it/en/catalogo/catalog ... gia-grande

This looks almost identical to mine, the difference being that I have the flip-flop version and that is just FG, from what I can tell.

When the LBS stripped my old nut (DON'T ASK!) they just pulled a replacement out of a drawer. I assumed that they were all the same, as the guy did it sort of without even looking.

urgh, the story continues... needless to say, I'm not using that LBS ever again. Even if they are willing to do minor things for me for free (which they are).

There are a couple of more reputable LBS along the road towards Camberwell, one seems to specialize in SG/FG. Perhaps getting down there and talking to them will be the quickest option?

[gerrymcm]

I think the size they've quoted 35 * 24 is the metric version of 1.37" by 24 threads per inch.
It's not the axle thread which is what I think you're looking at?

[Vladimir]

I think the size they've quoted 35 * 24 is the metric version of 1.37" by 24 threads per inch.
It's not the axle thread which is what I think you're looking at?

you are correct, I am looking at the axle thread because I want to replace the nut. This is exactly what I said in my email. Not sure how the words "nut" and "sprocket" got confused.

Looking around, it appears that I need to essentially choose between 9mm and 10mm threading (as these are the most common). What does 9mm/10mm pertain to? Is this the outside diameter of the axle thread? I can get the calipers around that and measure it, if that's the case.

[gerrymcm]

yep, 9/10mm is the outside size of thread so can be measured.
I think 3/8th however is 9.5mm so close, I've no idea what these hubs are more likely to be imperial or metric.
My guess is metric and if I had to guess to again, i'd say front is 9mm and back is 10mm.
Can you not try nuts from another hub, which is more easily checked online maybe?

[Vladimir]

yep, 9/10mm is the outside size of thread so can be measured.
I think 3/8th however is 9.5mm so close, I've no idea what these hubs are more likely to be imperial or metric.
My guess is metric and if I had to guess to again, i'd say front is 9mm and back is 10mm.
Can you not try nuts from another hub, which is more easily checked online maybe?

Thanks for the info. I only have one bike that is not quick release, and it is the bike in question.
Metric would make sense; after all the threads for the sprocket are given in metric.
They're Miche hubs, in case I haven't made that clear.
I'll measure the threads at some point soon and get a replacement nut with a floating washer; like it's supposed to be.

[Brucey]

the 35 x 24tpi thread is the sprocket thread, and as pointed out above it is actually an approximation to the actual thread size which is 1.375" x 24tpi.

On that model of hub the axle thread is either 10x 1 or 10 x 26tpi, with the matching front most likely 9mm, same pitch.

As per my previous post you can tell if it is 1mm pitch using a standard M6 x 1 screw as a pitch gauge.

cheers

[profpointy]

the 35 x 24tpi thread is the sprocket thread, and as pointed out above it is actually an approximation to the actual thread size which is 1.375" x 24tpi.

On that model of hub the axle thread is either 10x 1 or 10 x 26tpi, with the matching front most likely 9mm, same pitch.

As per my previous post you can tell if it is 1mm pitch using a standard M6 x 1 screw as a pitch gauge.

cheers

Was about to correct you on the M6 then read it properly. What a cracking idea - use an M6 screw (bolt to the uninitiated) as a 1mm pitch thread gauge - brilliant !

For the OP, it's well worth having a micrometer or vernier calliper for measuring this kind of thing correctly (diameter) then at least you're not guessing whether something's (say) 13mm or 12.7mm (half-inch) which is tricky with a ruler.
I've also got sets of thread gauges - but there are quite a lot of near-enough to confuse even with gauges, but overall diameter at least puts you in the ball park

[Brucey]

Was about to correct you on the M6 then read it properly. What a cracking idea - use an M6 screw (bolt to the uninitiated) as a 1mm pitch thread gauge - brilliant !

well it is quite a good wheeze if you don't have any pitch gauges, even if I do say so myself...

cheers

[drossall]

Perhaps getting down there and talking to them will be the quickest option?

Easily. They'll probably dig in a drawer and pull out the right ones. Even if it takes two or three tries, they'll probably have the right ones. Easier than trying to figure out what to order.