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I have the popular Shimano, Nexus 7 speed, internal gear hub. After removing the back wheel to replace the old tire, I've found that changing gears especially from 5 to 6 and 6 to 7 (especially the latter) is very tight.

It's however still possible, and all the gear shifting seems to work as it should, except the very tight pull required in the higher gears. The gears are adjusted (the red dots point at each other perfectly in gear 4).

Any ideas what could be causing this, and/or what I could do to fix it back to normal?

  • Welcome to Bicycles @Kurdunas. I've edited your post a little, but you don't actually ask a question. I suggest that you edit it promptly, so that it doesn't get closed. – andy256 Jul 14 '15 at 11:37
  • @Kurdunas, I think the edit could be as simple as "Can anybody suggest what I should check?" But, I'm new here too… – dlu Jul 14 '15 at 11:58
  • Is the wheel in properly? – Batman Jul 14 '15 at 13:54
  • @Batman yes, as far as I know. I was however uncertain how long in it should be, so I've tried to insert it in the same spot (using the marks). It could be a few mm off though. – Kurdunas Jul 14 '15 at 15:06
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    Have you checked the oil level? It seems like the mostly likely things are that something happened to the wheel/hub when it was off the bike (and very likely on its side and in other unusual positions) or that something is wrong with the way it went back on. But that said, have you followed the shift cable all the way back to make sure that is not hanging up on something? – dlu Jul 15 '15 at 2:03
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I am a fan of the Nexus drivetrain. Just had to say that. Anyways, the symptoms appeared when you removed and reinstalled the wheel. There are a couple of washers on each side of the axle that aid in spacing and keep the wheel in place. Two of these washers are called anti-rotation washers. They have tabs that fit into the channel of the frame and are square in the middle so they lock into the hub. My guess is that these are not installed properly. Under torque (high gear out of seat pedaling) the hub is shifting in the rear dropouts. The Nexus are sensitive to misalignment. The washers have to be inserted properly. The tabs must fit into the frame. Then the bolts have to be on tight, but not super-tight. Good luck!

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It's possible that as long as the No Turn Washers & any Spacers you used are all installed correctly that the problem may be as simple as over torquing the axle nuts that hold the wheel on the frame. There is a recommended torque setting for these nuts & if you just really wrenched on them when tightening that they could be binding the cassette joint & not allowing it to turn freely when changing gears. Easy way to check is to loosen off the nuts & see if the shifting improves.

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