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Old 04-14-17, 07:34 PM
  #16  
HerrKaLeun
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Join Date: Mar 2017
Location: Madison, WI
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Bikes: Giant Toughroad SLR1 and Motobecane Sturgis NX

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Originally Posted by Andrew R Stewart View Post
Is your front shift lever an indexed one? If so then A SunTour Ft der might not be intended to position it's self with a SRAM indexed lever. Either way about it SunTour has a rep for being a market cycle or three behind Shimano (who many regard as the gold standard of front shifters, something SRAM wishes for).


I did make the assumption that all was well with your front system originally as your said "My front derailleur can't shift in granny anymore, but even when it did I had some chain rub" (post 6). Granny chain rub after shifting is usually an adjustment thing unless significant cross chaining is at play. If this assumption was wrong I apologize. Yes, chain rub can be because of bent rings. And cheap cranks/welded steel rings can have some run out even when new. But the vast majority of the time, IME, these conditions can be worked with well enough to run well.

But I have seen vastly more bent rings from shifting under power, also bent ft der cages and twisted chain links. If this situation wasn't so prevalent then why (besides weight, tire width or suspension limitations) would manufactures market drivetrains with less ratios range/offers as an improvement?

I stand by my comments as holding up to many riders. As I often have said, my comments are not always about the OPs but also for the readers of the thread. Andy.
you make great points, really appreciate it.
I probably should have been more clear, chain rub was on the large chain ring back when the derailleur was set up to use all 3. It is indexed. The bike came with Suntour, and yes it not being SRAM like the shifters may be part of the problem. But even with cable disconnected it can't go to Granny. Who knows. I was fine all these years just having a 2x9. Maybe that derailleur is just a 2x and they jury-rigged it to the 3x shifter. This crappy derailleur is responsible for me wanting fewer chainrings Even if I pick the lowest line, always stay with SRAM or Shimano when I have a choice. Imagine my crank is the same quality as my front derailleur and you see how a chainring can bent without wrong shifting.

I analyzed my 3x9 of that bike and of my (new) 2x10 bike in Excel regarding ratios and meter/revolution (as one does). For the 3x9 I have 4 redundant gears, and extreme cross-chaining if I use all of the remaining gears. So I may have under 20 useful gears. Many of them very similar in ratio. So I may have 15 really distinctive gears if the granny worked.
In my 2x10 I have no redundant gears and since both chainrings are near the chain line I can cross-chain a bit more. Maybe I have 18 useful gears. My fastest gear is a bit faster. The 3x9 has 8.26 meter/rev and the 2x10 has 8.76 meter/rev
My slowest gear is a bit faster on the 3x9 bike. But that is a 22:32 on a 26" wheel, really not useful at all unless I tow a semi trailer. The 28:36 on 700c wheels really is sufficient for me. The 3x9 has 1.42 meter/rev (if the granny would work only) and the 2x10 has 1.78 meters/rev (and actually works).
I also found the front-derailleur on my new bike (it is SRAM X7 like the rear) shifts very well. I can see the SRAM chain ramps (SRAM crank). Now I actually don't mind to front-shift because I don't have to make those awkward paddle breaks etc. it just works (what a concept!) but since the rear ratios are so good, I don't need to on flats at all.
Maybe this isn't apples to apples because my 2x10 is a quality setup vs. the cheapo triplet. But fewer (but useful) gears seems to work better.

It looks like I can ride all flat parts in the large chainring and only off-road or uphill use all on the small chainring. That minimizes the times i need to shift on the front. since the rear derailleur shifts on the non-load side of the chain it shifts much smoother. Perfect for me. Doesn't' have to be perfect for anyone else.

IMHO triplets became obsolete when we went beyond rear 8. I guess they had the tooling for triplets and in marketing it sounded better to offer 27 gears instead of 18 for a 9er cassette.
I have to say, the 2x10 well done is leagues ahead of 3x9. I really love mine. I have my doubts 1x11 really works so well since one trades range for step-size. But I think for MTB (mostly slower) 1x11 probably is good. But I'm not an MTB person, so I'm just talking out of my a$$. A good 2x10 probably competes really well with 1x11 or 1x12. Especially on cost for the latter. More a matter of preference than technology. Both 1x and 2x are a compromise. but a better compromise than 3x.
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