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A lad in the school I work in approached me last week, asking me to take a look at his new bike. His pride and joy's freehub is borked and needs replacing. The BSO is only a couple of months old so I suggested that it go back for refund/ warranty etc.
However, his dad (on a very tight budget) bought it from a now disappeared eBay seller so is a bit stuck. Using a Shimano lockring tool I have now removed the cassette/ freewheel assembly. The unit unscrewed from the wheel. A large lockring retained the seven individual toothed cassette rings which i have now removed. Range is 14- 28t. I can find loads of matching items on ebay but I am uncertain about thread compatibility- are they all the same?
Looks like this:
But says XIN DU - T, not GREAT WALL CHINA.
Threads are normally the same. I volunteer at a bike collective, so see lots of BSOs. IME, they're all interchangeable. There are some obscure/obsolete standards, though (I wouldn't expect these to impact you).
https://www.sheldonbrown.com/freewheels.html
Bog standard freewheel. Easy swap once you get them off.
Cheers guys, I suspected as much but wasn't too sure.
Fortunately hub freewheel threads were standardised many years ago - it's also the same as a BSA bottom bracket thread 1.37"x 24 TPI.
Everything modern is normally ISO, its normally only if you do old/weird restos that you encounter problems, more info if you are curious;
> https://www.sheldonbrown.com/freewheels.html <
<table class="grid">
<tbody>
<tr>
<th>Type</th>
<th>Inch</th>
<th>Metric</th>
</tr>
<tr>
<th>Italian</th>
<th>1.378" x 24 tpi</th>
<th>35 x 1.058 mm</th>
</tr>
<tr>
<th>ISO</th>
<th>1.375" x 24 tpi</th>
<th>34.92 x 1.058 mm</th>
</tr>
<tr>
<th>British</th>
<th>1.370" x 24 tpi</th>
<th>34.80 x 1.058 mm</th>
</tr>
<tr>
<th>French</th>
<th>1.366" x <span class="highlt-r">25.4 tpi</span></th>
<th>34.7 x 1 mm</th>
</tr>
<tr>
<th>Metric BMX</th>
<th>1.181" x 25.4 tpi</th>
<th>30 x 1 mm</th>
</tr>
</tbody>
</table>