zacster

Will 10sp chain on a 7 speed chainring cause any problems?

I used an old 6 speed crank with 10 speed for awhile on a road bike, and while it didn't cause any mechanical problems, it was a bit chatty. I'm looking to upgrade my MTB to 10 speed, and I wasn't looking to swap chainrings. This is already costing me too much, and I'm beginning to think it won't be worth it, except that I'm picking up whatever bargains I can find, like $25 M591 shifters, and $40 M770 XT v-brakes. This is all after I built my dynamo front and rebuilt my rear. I still need levers and a cassette, and I'm shopping around all the usual places for more bargains, but these are getting hard to find, cassettes in particular. 9 speed would be a lot cheaper.

zacster

Another question is whether the 7 speed LX rear derailleur will shift 10 speed properly? I've read somewhere that it should, but if anyone has tried it I'd like to know.

Maybe I should take my own advice and go with friction and 10 speed like I have on 2 old steel road bikes. As I said above, the only problem is the chain is a bit noisy on the chainrings.

Crescent Cycle

Sheldon says it doesn't matter, but chainring spacing got slightly narrower with 9 speed and even narrower with 10 speed. There's a chance that the chain could drop in between chainrings.

7 speed has the wrong actuation ratio for Dyna-Sys 10 speed. It would work for 9 speed though.

Do you have a 8/9/10 freehub body? The 7 speed freehubs are shorter than the 8/9/10, which is shorter than 11.

What is your goal with more gears? Are you trying to get more range or what?

FastJake

As long as the teeth on the rings aren't too wide for the narrow 10S chain it should be ok. Like how you cannot run a 3/32" chain on an 1/8" cog. That's an exaggeration but the idea is the same. I doubt it will shift as well though.

+1 What's your goal here? More speeds does not necessarily equal better. The greatest number of speeds on a cassette I'll put on my personal bikes is 8.

With Shimano 10S road (STI) shifters it would work, but not with 10S MTB shifters. They pull a lot more cable, you need the correct RD. See: https://sheldonbrown.com/dura-ace.html

Crescent Cycle

Virtually all multi-speed chains are 3/32" wide inside with 1/2" pitch. I really am having a hard time thinking of any derailer chain that isn't. I vague recall there was a really really weird and discontinued 10mm pitch chain.

zacster

The only goal here was to replace all the worn parts on this bike, but you can't just replace one thing. Once you change one part, you have to do the next, then the next etc... There is only one type of low end 7sp shifter still available. I really don't care if it were 7 or 10. NOS 7 speed is hard to find, and not as nice as the current stuff. And some of this was just a bargain.

This started when I built a nice new dynamo wheel, and then also rebuilt the back wheel as the back rim was dented. I put those on and my old cantis, which weren't good to begin with, felt like they needed new pads and the cables were frayed, so for little more than the price of cables/pads I could get new levers/v-brakes (really, pricing seemed so out of line). So I bought those, then the shifters are attached to my current lever, so I needed those, and I found a pair of decent 10sp for less than any 7sp, and then the cassette and then the chain. Which is where I am. It is really only the cassette (also found a new 10sp take off) that threw the whole change over the top. I'll have to tally it all up, but I'm still under "the threshold"***.

The freehub body is 7 speed. I'm going to use 9 of 10 back there, but also may replace the body. This Dyna-sys may be a problem though I see now. If I need to change rear derailluer, I guess I will. Sheesh, why can't they keep things the same.

I have 2 different road bikes that have Campy down tube old style SR and NR shifters/derailleurs that I use with 10 speed wheels. One has a Shimano 10sp Ultegra cassette, the other a 10sp Chorus cassette. Both work flawlessly and silently. Everybody said it wouldn't work, 130 spacing vs 126, front chainrings won't fit, chain is too narrow, etc... I'm even running the Chorus bike with a 9 speed Shimano chain. No issues at all and no problem to install. I'm just hoping all this MTB stuff works out the same way.

And through all of this I saw that you can get new Giant carbon frames direct from China for a lot less than I ever thought. Hmmm.... A 10 speed, dynamo equipped carbon fiber commuter bike...

*** "The threshold" is anything under the SWMBO radar. Since I'm buying piecemeal, no one item garners any attention.

Crescent Cycle

If you don't care too much about the range you can pick up a Tiagra 10 speed cassette for about $30. I'm pretty sure the spacing is the same.

zacster

I found an HG-62 Mtb for that price. I'm up to $157 for shifters, levers, brakes, cassette and chain at this point. Nothing here is breaking the bank. Subtract out the price of new cables and pads, and I really needed a new chain too, and it isn't such a big deal for the entire upgrade. I'm hoping for crisper shifting and better braking, nothing more.

My wife's bike is a 2012 Specialized Vita (a WSD Sirrus basically) base model and it shifts and brakes much better. I'm just hoping for the same.

HillRider

The 7/8-speed crank should shift ok with a 10-speed chain but the narrow chain may tend to skate between the rings unless you shift quickly and not under high load. The 7-speed rear derailleur will work fine with any Shimano or SRAM 10-speed cassette but probably won't work with a 10-speed Shimano MTB shifter (Dyna-Sys)

Amesja

I've run 8-speed chain on vintage cranksets no problem. 9 & 10 speed might have a little more problems shifting cleanly and smoothly and you might have an issue with the chain getting caught between the rings with 10-speed but perhaps the chances of that are fairly low. You might be able to find at a local bike co-op a used 8+ ramped and pinned large chainring that fits your current crankset BCD which might help a lot, or even a whole used crankset with good rings on it for not much money. My co-op sells used cranksets for around $18. I've bought some really nice 8 & 9-speed cranksets with perfectly servicable rings on them there. Or just find a deal on a modern ramped & pinned large chainring online, maybe even a whole crankset.

I also have an issue with folks saying that you can't to find decent 7-speed shifters and such these days. That might be true if you are buying new but co-ops have buckets of used gear, many items are so barely used (as so many old bikes that get discarded are so rarely ridden) that they might as well be in "like new" condition after being cleaned up and over-hauled/lubed. If you want to rebuild a 7 or 8-speed drivetrain with nicer used shifters it is very easy to do. 8-speed is a little easier as there are still a lot of new shifters available on Amazon and at other online bike wholesale sites. The Ultegra 8-speed bar-end shifters are under $80 for the entire kit which includes cable stops for the frame, cable, housing, everything you would need except the derailleurs and the bike to hang it all off of.

zacster

There may be a lot of used 7/8 speed gear, even lightly used, but these are still pretty clunky. I've seen the newer stuff and it just works better. My wife's cheap shifters/derailleurs outperform my old Deore DX on my old Trek by a lot. It all just works, click, click click. My kids use that bike without any problem, whereas my other kid tried using my old trek and couldn't shift.

This is all mtb gear too. No Ultegra here. And BTW, I used Ultegra 10 for the first time just last month on vacation. I hated it. I'd much rather use Chorus 10 like I have on my road bike. (That should start a flame war). This is part of why I'm upgrading, I thought I deserved a commuter that worked as nicely as my road bike. And as I've said, even my vintage steel road bikes work flawlessly with the kluge of 10sp with friction. 1990 7 speed wasn't anywhere near this. Clunky at best.

zacster

Well, after reading as much as I could about dyna-sys, I've decided that I don't want it. I'll go with 9 speed instead. Everything is a lot more compatible. I bought the M591 shifter, the HG62 cassette and a KMC chain. I'll try to sell the shifter and cassette (anybody want them? pretty cheap!) and buy the 9 speed equivalent. I'll keep the chain for my road bikes. It was never about the speeds, it was about the better parts. For that matter, I could get away with 3 speeds, which is all we have on Citibikes.

I checked my log for 2013 and found that about 1/3 of my miles were commuting, so why not have something that works well. And besides, this has become a bit of a hobby to work on bikes. I surprise myself that I can make stuff work silently and smoothly.

I have the HG 62 cassette in my hand now, and it doesn't have the last 4 cogs on a spider, it has 8 cogs riveted together! Only the 2 smallest are loose! Each cog is stamped with the # of teeth. I guess Shimano wants DynaSys to work as a unit. I may try this in spite of what I said above. A new rear derailleur will cost about $50 for an SLX.

I just did a long car trip with my wife and daughter, auditions at Michigan State (GO SPARTANS!!!) and the subject of my bike upgrade came up. My wife didn't care about the money as long as I was satisfied. Compared to the trip just for the auditions this isn't all that much. East Lansing, Michigan is damn cold!