front chain ring wear on a triple
fatsmoker
Posts: 585
There' are 2 questions at the end of this meandering story, so be patient, please.
I have a triple front chain ring (30, 39, 52) on my Spesh. The last time the middle ring wore out the chap in the shop wondered aloud if I ever used the big ring. Not often was the answer as most of my riding is to and from work with traffic to slow me down, so the middle ring is generally fine up to 18 or 19 mph. Since I had the ring changed it has worn out again (teeth are sharp in a couple of areas so the chain slips). Big ring is fine. Since the first change, I made a big effort to use the big ring more but it menas shifting between big and middle ring 3 or 4 times every 7 mile commute. Is the regular changing from big to middle ring the cause of the fairly quick wearing out of the middle ring? It's been about 10 months of about 90 miles a week. I never use the little ring - would I get better wear from a compact double where i'd probably spend more time in the big ring?
I have a triple front chain ring (30, 39, 52) on my Spesh. The last time the middle ring wore out the chap in the shop wondered aloud if I ever used the big ring. Not often was the answer as most of my riding is to and from work with traffic to slow me down, so the middle ring is generally fine up to 18 or 19 mph. Since I had the ring changed it has worn out again (teeth are sharp in a couple of areas so the chain slips). Big ring is fine. Since the first change, I made a big effort to use the big ring more but it menas shifting between big and middle ring 3 or 4 times every 7 mile commute. Is the regular changing from big to middle ring the cause of the fairly quick wearing out of the middle ring? It's been about 10 months of about 90 miles a week. I never use the little ring - would I get better wear from a compact double where i'd probably spend more time in the big ring?
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Comments
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Why not just swop your 52T for a 50T, if it is a 130 BCD chainset?0
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I use the 52 ring much more now as I'm riding generally faster (raised the seat a bit the other week which helped no end). A 50 with a 39 seems a bit close.0
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On my winter bike with a 105 triple I spend 90% of my time in the middle ring. TBH I can't be arsed changing. The big ring is for tailwinds and long downhills, both of which are quite rare round here.
About to replace my middle chainring, chain and cassette. Big and small chainring are still good0 -
fatsmoker wrote:I use the 52 ring much more now as I'm riding generally faster (raised the seat a bit the other week which helped no end). A 50 with a 39 seems a bit close.
My Tricross from 2011 has a triple up front. 30/39/50
The hop between 39/50 is quite nice - far better than the swap between 34/50 and not noticeably different from 39/52 or 39/53.
I ride rode with a 23/12 (9speed) cassette as it gives nice close ratios (and I still have the 30 ring if needed or I can't be arsed). TBH, I spend most of my time in the big ring - but then my journey is quite smooth with only a couple stops/starts to worry about.
I wouldn't think the change of ring is causing the wear unless the chainlines are way out - just checked, my Tricross has done >3000, 2 cassettes that are swapped around, just put the 3rd chain on, used in all weathers and not kept pristine - the chainrings seem fine.0 -
I don't really see why 3 or 4 chainring changes per commute is a problem unless there's something wrong with the front derailleur setup. When you need to change gear, change gear!
My last bike had a 50/39/30 triple and I usually rode it with a 12-27 cassette but occasionally with a 12-23 on flat and fast cycles. When I started I think the middle chainring got most use but soon for moderate to high intensity rides on the flat I would typically stay in the big ring and use the middle of the cassette. For easy rides, headwinds or small hills I'd switch in and out of the middle ring as needed. That bike has probably done about 20,000km to date and I never needed to replace a chainring. If you're trying to avoid changing chainrings which it sounds like you might be doing, then perhaps you are often riding with a big angle on the chain ("cross chaining")? This could potentially lead to increased wear and I suspect it's a much more likely cause than changing gears.
Edit: Just read Slowbike's post. Mine's a Tricross too, the 2009 model. Approx 20000km, replaced the chain once about 10,000km back, 3 cassettes have been used and all still fine (the oringinal 11-32 doesn't get used anymore!). No replacement parts in the drive train aside from the chain and no reason to believe it would need any in the near future. Like Slowbike, mine's been used in all weathers and is not kept pristine. I clean the chain from time to time but not regularly.0 -
Ai_1 wrote:If you're trying to avoid changing chainrings which it sounds like you might be doing, then perhaps you are often riding with a big angle on the chain ("cross chaining")? This could potentially lead to increased wear and I suspect it's a much more likely cause than changing gears.
I'm defo not cross chaining in the middle ring, hence it concerned me that the middle ring has worn so quickly in 10 months. 3600 miles or so overall, so I would guess 3000 miles in the middle ring.0 -
My 105 middle chainring is over 6000 miles old and probably got some life left in it. Proper mudguards for the 11 rainy months and frequent, possibly premature chain replacements probably helped.0
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I'd be expecting it to keep going for many more miles. Like I said my Tiagra rings are more than double that mileage and still servicwablekeef66 wrote:My 105 middle chainring is over 6000 miles old and probably got some life left in it. Proper mudguards for the 11 rainy months and frequent, possibly premature chain replacements probably helped.0
