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I recently bought a revolution cross 1 and after a week I've bent the middle chain ring quite badly and the outer one a bit, I think by spitting a big rock out from the front wheel and unfortunately it then smacked right into the crankset.

I was a bit surprised (my own fault for not checking) to find that the chain rings are riveted and so I now have to buy a new crankset. I've looked around for other square taper BB cranksets with removable chain rings, but what look like higher quality components say they are for 8/9/10 speed cassettes and I have a 7 speed freewheel.

I'd like something that will not bend on contact with a rock ;) Failing that something I can swap out the chain rings on without buying the whole shebang.

Any ideas?

Thanks in advance,

Tom.

  • You could try unbending the chainrings. Note that at the lower end, replacement chainrings cost about as much as a replacement crankset, so you may economically end up going for something quite similar to what you have. – Batman Aug 5 '16 at 14:11
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    You could move to one step up in the SR Suntour range to the XCE, their still rather inexpensive, compatible with 6/7/8 speed, and have bolts not rivets and are available in the same ratio (48/38/28) in a 170mm. They have a chain guard but it is removable. – Nate W Aug 5 '16 at 17:37
  • The trick is not do drop the whole weight of you and the bike onto the chainring in the first place. Chainrings that don't bend when you hit a rock are very hard to find, because they're also ridiculously heavy and expensive. You're looking at a 1x setup with a 10-15mm thick "chainring" where the actual chainring teeth are almost afterthoughts on the big slab of hardened titanium. Most people use disposable chainring guards, and replace the chainrings when they need to. – Nuі Aug 5 '16 at 23:51
  • Yeah, that's not what happened, rock about the size of a cobble stone got thrown up descending by front wheel and smaked the crank. Bash guards are new to mw, I'll look into them, still though, I am somewhat dissapointed that my chain rings succumbed quite so easily on their first impact. Surely there are better options (apart from picking a better line ;) ) – Tom Rhodes Aug 6 '16 at 17:31
  • If Nathan's answer addressed your question, could you please mark it as "accepted" by clicking the little tick/check mark on the left side ? – Criggie Jun 16 at 1:12
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If you want something nice, using an 8/9/10 crank here shouldn't be a huge problem but it may take some fiddling to work well. If it says 10, you will probably have to use .6mm Wheels Mfg spacers or similar under the large and small rings to avoid chain rub in some gears. Putting on an 8-speed chain will also help eliminate that problem and should still work fine with your 7-speed freewheel and FD. Narrower than that and it won't work well with your FD.

Shimano Acera FCM-361 or the Suntour XCE mentioned in the comments are other options that would be drop-in replacements unless you needed to change spindle lengths. The Acera takes 126. It would be nice to assume that going from one Suntour crank to another very similar one that the spindle needed would be the same, and it's probably true, but I wouldn't be shocked if it isn't.

  • Thanks, I've been recommended a sugino xd2 triple too, I think the key is just having replacebale rings, then replacing what you have with better if you get unlucky. I'll have a look at these options, I think you are right abotu the BB too, I 'm not 100% sure they will just drop in. Do you know the Sugino XD2s? – Tom Rhodes Aug 6 '16 at 17:34
  • Sugino XDs are great cranks but your FD (presuming its the stock one for your bike) has a maximum tooth difference of 20t and all the versions of the XD2 I've seen are 24/3x/46 or 24/3x/48. (That number relates to the "height" of the cage; the chain will drag on the bottom of the cage in the small/small combos if you exceed it and it's ramping/profiling may not be in quite the right place. OTOH if you stay out of small/small combos, it may work fine.) The 26/36/46 XD cranks like XD300 and XD600 would work. Also you'll probably need a new BB with Sugino too. – Nathan Knutson Aug 6 '16 at 18:48
  • I've found a Sugino XD2 in the UK with a 28/38/48, so that's right on the 20 tooth limit as is the original so hopefully would be ok, I will compare with your other options. Thanks loads Nathan, I've accepted your answer as between the answer and the comment you've covered all the bases I needed. – Tom Rhodes Aug 7 '16 at 19:19

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