Replaced large chainring but can't now use full gear range.
small_bloke
Posts: 222
Replaced the large chainring (50T 110BCD) on my shimano 105 compact 10 speed chainset 2011 5700 model.
But now when I use the small inner chainring gears (34T front) in high gear at the back, i.e. small-small, the crossing of the chain seems to catch on the bottom of the large chainring creating a slight rubbing affect. This feels like a sticking effect when your pedalling, a bit like slipping. (by "slipping feeling" I mean when the chain has worn and you don't replace all the drive train at the same time). I cant use the last 4 high gears on the cassette when on the 34T front chainring.
New chainring - Stronglight Dural from Spa Cycles.
http://www.spacycles.co.uk/products.php ... b0s149p293
The chainring bolts have all been placed back in the same way and tightened up. Not reversed or anything.
The bike is new and only done 50 road miles + 200 Turbo trainer miles. I replaced the chainring as I didn't want to wear out the expensive Shimano 50T chainring on a turbo trainer. (Thats seems to be where its sitting for the winter period until summer arrives). I have another winter bike.
The only thing I didn't do was check if there was any small arrow on the new chainring which sometimes has to be matched up in line with the crank arm. All the teeth looked the same on the Stronglight ring rather than shaped differently in some places such as Shimano or SRAM original rings.
I'm wondering if there is some compatability issue? Do I need a chainring bolt spacer (if there is such a thing) somewhere?
Also checked the chain with Park Tools chain wear indicator - not worn out.
Please help!
But now when I use the small inner chainring gears (34T front) in high gear at the back, i.e. small-small, the crossing of the chain seems to catch on the bottom of the large chainring creating a slight rubbing affect. This feels like a sticking effect when your pedalling, a bit like slipping. (by "slipping feeling" I mean when the chain has worn and you don't replace all the drive train at the same time). I cant use the last 4 high gears on the cassette when on the 34T front chainring.
New chainring - Stronglight Dural from Spa Cycles.
http://www.spacycles.co.uk/products.php ... b0s149p293
The chainring bolts have all been placed back in the same way and tightened up. Not reversed or anything.
The bike is new and only done 50 road miles + 200 Turbo trainer miles. I replaced the chainring as I didn't want to wear out the expensive Shimano 50T chainring on a turbo trainer. (Thats seems to be where its sitting for the winter period until summer arrives). I have another winter bike.
The only thing I didn't do was check if there was any small arrow on the new chainring which sometimes has to be matched up in line with the crank arm. All the teeth looked the same on the Stronglight ring rather than shaped differently in some places such as Shimano or SRAM original rings.
I'm wondering if there is some compatability issue? Do I need a chainring bolt spacer (if there is such a thing) somewhere?
Also checked the chain with Park Tools chain wear indicator - not worn out.
Please help!
0
Comments
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at first i thought it was simply due to 'cross chaining', going small-small or big-big
this puts the chain at a more extreme angle, increases load/wear, and often the chain can rub
even if it didn't make a noise, it's still best not to cross chain
in general...
on the small ring, avoid using the smallest two cogs
on the big ring, avoid using the largest two cogs
but you say you can't use four cogs, that does suggest something else is wrong toomy bike - faster than god's and twice as shiny0 -
Stronglight rings seem to sit closer together than Shimano when fitted to Shimano cranks. I had a similar problem when I fitted 52/38 Stronglight rings to my Ultegra compact chainset. The answer was to fit shim washers between the crank and the big ring. Google for 10mm shim washers. Try to get 0.5mm thick or less so you can adjust it just right.
I don't think you would wear your chainring out much on the turbo anyway. And those dural ones don't last too well. The Zicral are far better.0 -
Thanks for replies so far.
In the meantime I have tried the following by re-adjustment.
Loosened all crank bolts and re-tighened to very light finger pressure working in a opposite fashion to each respective bolt. Then increased tension slowly as I went round. Just incase the chainring had a slight wobble if they weren't all tensioned correctly. Tried this numerous times. No result.
Tried removing both chainrings and remounting. No result.
Retested with original Shimano 105 chainring. Good result - no chain rub or skipping.
Conclusion - I think the Stronglight chainrings have some minor differences and don't work with Shimano cranks too well (just like John.T said above).
Out of interest I might try how the Stronglight chainring fits Sram Rival cranks instead of Shimano on the weekend (on the other bike).0 -
I swapped the 34t on my Sora 9 speed for a Dural 38t keeping the standard large ring.
It's working on all gears without any hassle.
Use shims as advised.
I wouldnt worry in the slightest about wearing a chainring on the turbo though and still wouldnt use small/small.0
