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My bike has an aluminium frame and I measured 134mm rear dropout spacing. The wheel it came with has 130mm OLD. The dropouts are quite a bit flexible, the QR pulls them in on tightening. This is the wheel it came with as far as I remember. I am the first owner, but rear and front rims while looking very similar don't quite match. Cannot remember to have (had it) changed.

I am driving this bike for years and thousands of kilometers without breaking the dropout. After a recent need to replace the sprockets and discovering that even the 12-34 megarange freewheel is not available any more I decided to upgrade to freehubs and cassettes. Got a used 7-speed hyperglide wheel to match the measured 130mm OLD of my old wheel and transplanted a current 8/9 freehub onto it, staying at 130mm OLD. Conversion is done for some time and drive quite a bit with it, but there remains a nagging thought:

134mm is a weird spacing, isn't it? I checked with bolts, the dropouts are parallel, unclamped, and they still look parallel clamped to 130mm.

Could this be a 135mm frame, set to less dropout spacing by long use of a 130mm OLD wheel? And is 130mm OLD the way to go, here?

Before transplanting I tried putting in wider hub: pulling the dropouts slightly apart I was able to get it in. The 130mm hub is easier to get in and out and I have been using such for years and miles. On the other hand, 135mm is "closer" to 134mm and would allow for less dishing.

  • Aluminium cannot be cold set - I'd start by rechecking the measurements with a vernier caliper, or ask someone else to check independently. – Criggie Mar 12 '18 at 18:43
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    I did not imply any cold-setting. However, aluminium bends. And likes breaking on any bend "back". That's what makes me wonder whether 135mm OLD hubs are fine to use on this bike. This set aside, I am confident in my measurements. Actually, I measured somewhat less, 133.8 but given the imperfection of the surfaces, I rounded to nearest mm. – aspseka Mar 12 '18 at 19:12
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Your frame is most likely intended for 135mm spacing and measures 134mm either because of manufacturing tolerance or because it was bent by using too narrow hub. The angle difference between 130mm and 135mm hubs is about 0.4 degrees, which is not really visible to naked eye.

135mm would be the way to go, but there is no immediate danger from keeping using 130mm either.

  • If you're going to buy a new hub or wheel consider buying a 135mm version since it is closest to the actual dimensions of the drop-out and will put less stress on the stays. And because the the RD will be pushed less to the left when you close the quick release shifting might become more precise. – Carel Mar 12 '18 at 20:50
  • The RD really should be adjusted when the quick release is tightened. – ojs Mar 12 '18 at 21:00
  • @Carel Is that really the case? Referring to my comment to the question, wouldn't it hurt the frame to be "bend back"? – aspseka Mar 13 '18 at 0:59
  • And I don't have issues with the (new) RD - although tbh I would have to check whether the hanger is aligned to accomodate for the 130mm "distortion" (since I believe the bike came with that). – aspseka Mar 13 '18 at 1:05
  • I'll be accepting this answer although I am still unsure about the stress inflicted to the dropouts by going (supposedly "back") to 135mm. – aspseka Mar 19 '18 at 17:33

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