5

I have a Dutch town bike with backpedal brakes (omafiets). I live in Amsterdam where it's flat and have checked the tires are fully inflated.

Originally the bike was very easy to pedal and often it still is. However, sometimes it feels about 20-50% harder to pedal. For example, flats feel like small upslopes and long upslopes feel intolerable. I'm trying to account for the slope, wind and my own tiredness. Occasionally it feels like I turn a corner and it's suddenly easier or harder. I'm often doing the same routes with different perceived difficulty.

My feeling is that something is sticking on the rear wheel. I have occasional perceived a small dragging sensation whilst pushing the bike with my hands (dismounted). My assumption is that the brake is slightly sticking. Two different bike shops have told me that this isn't possible. There is some slight side-to-side play in the wheel (about 1-2mm at a guess).

First bike shop said it would be the side-to-side play, second bike shop agreed so I had them fix it. They replaced the chain, pedal attachment, rear wheel and rear axle at significant cost relative to bike value. This did not help. Recently went back and they said the wheel is loose again, suggest tightening again. Of course, I'm doubting this is the problem.

I've read that cone adjustment should be done in this situation. However, my understanding is that tightening the wheel will actually make it harder to pedal - the adjustment is a trade-off between ease of rotation and stability of the wheel. Do I understand correctly?

Any other ideas on what could be causing this?

  • 1
    Get a new bike shop. Replacing bits while hoping it fixes the issue is a sub-optimal way to keep customers. How technical are you? Do you want to fix it yourself? – Criggie Jul 8 '16 at 8:26
  • 1
    Generally technical, done some bike repair but would be a bit trepidatious opening up the rear unit. Do you expect the brake to be sticking? – Sam Brightman Jul 8 '16 at 8:35
  • Needs more diagnosis - can you stick the bike in a workstand? Or hang it from some cords from a rafter? Mind out for finger-munching moving parts of course. You're trying to find a cause; or something that is wrong. So the normal process is to cut the problem in half and see where the symptoms move to. Try completely disconnecting the rear brake and see if the problem goes away in the stand. Is your rear wheel straight/true? – Criggie Jul 8 '16 at 8:37
  • Check if tyre is not rubbing against fendes or screws of fender holder. – krzyski Jul 8 '16 at 9:14
  • @Criggie he cannot disconnect rear brake I guess, since it's internal hub brake – krzyski Jul 8 '16 at 9:17
4

Are you sure you don't have a kick shift/kick back hub in the rear? I had this exact problem after I bought a new, used rear wheel for my town bike.

Seemingly at random it would be much harder to pedal, sometimes forcing me to hop off and walk up hills. At other times I'd be able to ride up the same hill! I thought I was going mad, and I too thought something was broken. After a while I noticed a pattern, that it was changing in "difficulty" whenever i braked, ie. backpedaled. Now I love it, easy, hands-free shifting!

Sheldon Brown glossary page: http://www.sheldonbrown.com/gloss_i-k.html#kickback

  • I had never heard of this. I don't think so; Dutch people I ask have also not heard of it and it's not a special bike. How obvious is the shift? – Sam Brightman Jul 29 '16 at 7:23
  • The shift itself is smooth and unnoticeable (ie. there's no sound or vibration) but the difference in gearing is very obvious when you realize what's happening. My test was to pedal along a flat, straight road. I kept the same speed and observed my cadence (pedaling speed). Then I backpedaled (shifted gears) and pedaled forward again. My cadence would change quite drastically (faster or slower) while maintaining the same speed along the road. Conclusion: the gearing has changed. – chfr Aug 3 '16 at 9:22
2

It could be time for the rear hub to be overhauled (btw, I love the omafiet style of bike. Good memories). This is not a hard procedure, and you can do it if you take your time.

A likely cause is that the grease used to pack the rear hub, and aid in the clutch engagement for drive and stopping, is worn out. I suggest you go to the Park website and take a look at how it's done.

Coaster Hub Overhaul (Pedal Brake Hub)

Most of the bikes I saw and serviced of this type had seen a lot of abuse and rain. It wouldn't hurt to replace the bearings at the same time as you will need to remove them anyways. Good luck and let us know how it turns out!

  • Note that Park links go out of date quite quickly, there seem to re-arrange their website fairly often (bicycles.SE has a lot of these, unfortunately). So while in general we discourage link-only answers, links to the Park site are especially bad. I've replaced your text description with the actual Park blog title in the hope that people in the future can find it again. – Nuі Jul 9 '16 at 5:40
  • @Nui: Still learning. Good point. Thank you! – user26705 Jul 9 '16 at 10:51
  • To quote Opie: They replaced the chain, pedal attachment, rear wheel and rear axle at significant cost relative to bike value. I would read that as meaning that the rear hub was completely replaced. – Daniel R Hicks Jul 9 '16 at 21:30
  • Vagaries of English? I have no idea what a pedal attachment is either. But if read directly they replaced the entire rear wheel with the hub. You get that one :) But in context it sounds a lot more like they stated they replaced/repaired parts. An used, acceptable Batavus can be had for about $200 USD. I do not see how a new rear wheel with hub would come under $175 USD on a good day. So knowing that the last thing a shop would do is what I recommended. Repack rear hub, address bearings (which may be the issue as OP states change in drag during corners). – user26705 Jul 9 '16 at 21:48
1

If the nuts holding wheel to frame are too tight it will do this. Quick release has this issue a lot. Beyond that it sounds like a bearing problem (repack and replace). Spinning wheels while bike is upside down will show which wheel is dragging.

Your Answer

By clicking “Post Your Answer”, you agree to our terms of service, privacy policy and cookie policy

Not the answer you're looking for? Browse other questions tagged or ask your own question.