Overanalyzing 1×10 Mountain Bike Drivetrains
I recently made the decision to convert my fun bike (2011 Trek Remedy 9.9) over to 1×10. While I really enjoy the bike as it is now, on our local trails with the standard 2×10 that came with it, I found I spent a lot of time in the “wrong gear” as I felt I was either too fast for the little ring or the short steep sections were too much for the big ring.
I have an X0 2X crank on the bike, so the 120/80 BCD spiders did not give me very many options, especially to keep a nice chain line, but thankfully MRP created the “Bling Ring” for my situation; a chain line offset single ring that replaces the spider on my crank. (disclaimer: I paid full retail for the MRP parts in this article) It was very easy to install and works great. It took me a while of messing with gear ratios/calculators to settle on the 30T ring. While the standard 1×10 front ring is a 32, with the longer rides that I do and steep terrain of our area, I thought the 32T would be too much. With the 30T, I give up only my previous shortest and 2 tallest gears. There are hardly any times when I was in the 11 or 12 tooth rear with the 39T front big ring, or in my granniest of granny’s (26T front/36T rear), so I figured this was a good compromise. The below chart shows the gearing on the 30T with the shortest (36T) and tallest (11T) gears, as compared to my 2×10 on the 2nd shortest (32T) and 3rd tallest (14T).
The front is a bit more complicated as I needed some chain retention. A few weeks ago I converted to the SRAM X9 Type 2 rear derailleur and it’s worked very well. It does a good job of eliminating chain slap and retention on the bottom, but I still need something for the top to keep the chain from bouncing off the top of the front ring. The Remedy has a direct mount FD and a press in BB, which eliminated most of the common simple chain retention devices out there. Again MRP came to the rescue with the MRP 1X Direct Mount guide. This is a simple guide that attaches where the front FD used to. Took a light bit of filing work to get the guide low enough for my 30T ring, as MRP recommends it only for a 32T or bigger, but it worked out.
MRP 1X Direct Mount guide
I have to say that I fell in love all over again with my Remedy. 1×10 is so simple and takes a lot of thinking out of riding. It almost gives me that single speed feel in a way. Super quiet, no chain slap, and not much to think about. Wanna go faster? couple of clicks, want to go slower? couple of clicks. No need to worry about cross chaining, chain slap, chain suck. I haven’t run out of gear yet on single track anywhere. Doing some gravel road descents I have spun out, but this is the “fun” bike after all. If I’m going > 20mph I’ll either let gravity take me faster or just relax on the pedals. I would highly recommend the 1×10 setup to anyone trying to take some weight off their trail bike or looking for something a little simpler.
SRAM Type 2 and Shimano Shadow Plus: Battle of the 2012 Derailleurs
Both Shimano and SRAM are out to fix an issue that has plagued the mountain biking community since the beginning…chain slap. Their answer? The new rear derailleur offerings from each side of the shifting camp are now clutched/damped versions with the ability to run a tighter chainline with a flick of a switch or push of a button.
As suspension designs have changed over the years and more travel has come to XC oriented bikes, the issue of chain slap and dropping while riding has become a hot button issue for a lot of riders. While this could be fixed with a roller install like you see on almost all downhill bikes, the trail and XC crowds were not keen on the additional drag this added to chain lines. While I can see their point as increased drag equals great power output required per revolution, I always ended up just adding a bashguard and roller to my bikes for the increased protection and tighter chain line.
However, things have changed in the mountain biking industry. As carbon frames have increased in popularity, so have BB30 and similar bottom bracket setups that do not allow for the external cup/sandwich style roller setups. To get a roller setup like the MRP we have reviewed in the past, you had to have ISCG tabs on your bottom bracket which most bikes do not have. Additionally, most of the 2x cranksets do not allow for a bashguard.
Enter SRAM Type 2 and Shimano Shadow Plus…
Now with these new rear derailleur designs, you can tighten up the chain line while riding to prevent that annoying chain slap and help keep the chain on the rings while riding in technical terrain. Each of these manufacturers have implemented their own technology and the ability to turn the feature on and off at will.
SRAM clutch mechanism is a one way, needle bearing roller clutch that requires no maintenance as it is self lubricating and basically sealed. Shimano uses an adjustable friction clutch where the rider can actually dial in how much he wants the rear derailleur to not allow the chain to pull the cage forward. Either way…SRAM and Shimano are trying to help the rear derailleur from being pulled forward by the chain in technical riding situations where the suspension is as active as the chain moving.
Will this be enough to replace roller systems? We’ll see. Both technologies from SRAM and Shimano are in first gen releases to the public and from what we are hearing around the world…they work great but aren’t quite on par with a true roller setup yet. The good news – those riders that wouldn’t run a roller setup to begin with now have a viable option to get rid of chain slap, have more consistent shifting through suspension travel and prevent the chain from dropping off the rings.