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2 x 10 Set Up
NB: Originally posted elsewhere on the Global Riders Network and appears via syndication.
I am currently running a 2 x 10 set up on my 29er (38/24 Chain Rings and 11/36 cassette) and was wondering what other riders in the 2 x 10 29er crew are using? The reason I ask is that while I like the lower chain ring/cassette ratios, I can hardly tell the difference between the 29er and my old 26er granny gears, I often find myself spinning out of control when I drop down from the large to the small chain ring, it seems the difference between the two is too great. Has anyone else experienced this problem? I'm thinking I might have to go back to a 3 x 10 set up to get a better spread of gears.
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not a 29er rider, but i can figure out the math part. the front differential on a 3 ring is usually 22 to 32 or 24 to 32 - so call it 10 teeth (5 inches presumably). on your current setup the difference is 14 teeth - thats a big difference - especially when the rear teeth make little difference compared to the front teeth.
So instead of having 3 useful gears on your granny (as you had before), you now have about 6 useful gears on the granny. - so you have a much bigger differential, so a front gear change change you down somewhere abouts a 1/3rd I think. on a normal setup, the next easiest gear when you are in middle, is go to granny, and go down a gear on the rear - ie flick both short levers together to go to the next easiest gear - you now need to flick down 2 on your rear, possibly 3 to get the next easiest gear when you move the front.
You just have to ride different, and learn the bigger spread you now have.
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Yeah I think you are right I was just talking to someone else about having to change the way I use/change my gears
Had 2 29rs and experienced the same problem. However for me the gearing on a 29r was just too high with 24/38 & 11/36. The granny wasn't low enough for my pathetic climbing ability and the jump between rings was too high. So changed my 2*10 to 3*10 but used 20/30/40 front rings with 11/36 cassette. For me this was good as it gives the same revs/speed gearing as a 26r and the jump between front rings was sweet.
Went back to 2*10 but kept the 20 granny so tried 20/36. The jump between the rings meant that I had to change 4 or 5 gears on the rear. Even though the SRAM lever will drop 3 gears at the rear in one movement, this was still too much. So went to 20/33 which now almost perfect for me as I don't often go over 40kph on the terrain I ride and can use all 20 gears and the jump between gears is manageable. 33/11 @ 100 cadence is 42kph approx. (went 33 as trying out a Rotor ring)
However, for the Karri I may just go back to 3*10 and just add a 40 front ring which will give me 50kph approx @ 100 cadence which I may need on the long downhills in the Karri course.
If you do a lot of climbing on 15%+ grades, I would suggest you think about going to a lower granny 20 or 22. If you are a strong climber (curse you all) this may not be necessary.
FWIW
Have tried 26/39 and 24/28 on 29ers (11-36 rear), while some people have no problems pushing these gear ratios, for me the 24 is probably the limit, I’d put a 22 on if I had one. I’ve done a 5 day MTB race with the 26/39 front that had me off walking hills where the guys and gals with granny gears would spin past me at a blistering 5kph.. damn!
The last race I did on my 29er was at Awaba and I never even got out of the 24 front ring.. (yes I was spinning my ass off) I think that this is mainly (apart from having a crash every other minute) because I have developed some crazy psychosomatic aversion to shifting the front ring in a race as moving up/down 14T up front is soo horrible and noisy (the birds stop singing and babies begin to cry) either that or I’m just afraid that they’d exclude me from the peloton as a punishment for my bike making a most horrible shifting noise like that?
I recently rode with triple (XT) rings and was immediately blown away by the sweet shifting, could it be that my 2x10 days are indeed numbered? Its definitely a case for sticking to 3x or single front ring set ups from now.. BAH@! A pox on those horrid shifting noise ratio compromising chain sucking 2x front rings!
Well the 24/36 front/rear granny ratio is fine for me; however, it's the 24/38 difference up front that's doing my head in. So what I am going to do is go back to a triple set up (XT)because what I like to do is to set the rear cassette at 3 or 4 and then firstly change my chain rings when the going gets tough then drop down through the cassette, it's the way I like to ride and I'm too old to start rethinking my gear changes. So thanks for the feedback fellas.
I was wondering about the granny gear on the double, as my fitness tends to vary a bit and sometimes I need the 22/34 (maybe I should just fall off and hurt myself less :embarrassment: ) but the impact of the 14T+ difference on the front hadn't really occurred to me.
Having to take two bites with the right shifter to get the desired rear cog would be a major pain and be more likely to jam up the transmission if you had to do it under load.
I've read some hints on line that doubles drop the chain off the front more often than triples - is that something you guys've found?
obmal mate, you crack me up
Haven't had my chain drop off at all, but then I've only had the bike for a short time so who knows? Anyway it's a moot point for me now as I've made the decision to go back to a triple set up.
i have a feeling your front chain rings are what is causing all the greef, the 38 - 24 is too big of a gap, try a larger inner ring, i would look at a 26 at least, from memory the shimano are good for a 18 tooth overall jump, on a triple but only 10 teeth when jumping from middle to top which is why most shimano cranksets run a 24 granny and a 42 big, or a 26 /44, sram from memory are very similar but im not 100%, my guess is the jump from 24 up to 38 is too big
I dont think your problem is a 29er one, but a 2 X 10 problem. My understanding of the 2 X 10 setup was that part of it's purpose is to eliminate double shifting. one of the consequenses of this is that there will be big differences between the gear sizes on the front and rear chainrings. As in, the system is actually designed to have a massive difference.
so i dont think it is so much a problem, just something your not used to.
I can't help feeling this ten speed thing is a bit of a con. You're getting rid of a 22 tooth cog and adding a 36 tooth cog? Sounds like a backward step to me.
I have the same biker (well, the Expert version) and there is obviously a big difference between both the 3x9/2x10 and the chain rings but I haven't had any issues at all and I have classically been a terrible shifter! I think I find that I shift less now but am maybe a bit smarter about it. How long have you had the bike? I know you said you have made up your mind but is it with sticking with it as I am now very happy with my 2x120 setup to the point where when my old bike needs a new drivetrain I reckon I will go the same way.
I've had it for about three months now, however, haven't done a lot of riding because in that time I've also had my shoulder reconstructed. I was always going to change the setup, even if not to a 3 x 10 then a more up market 2 x 10. I have an Epic 26er as well and when I was looking for a 29er took the Expert for a couple of days and essentially didn't buy it because I don't like where the Brain adjustment was placed and again would have swaped out the original group set. So my intention has always been to fit my new bike out with XTR and XT components, however, I think I really do prefer a 3 x 10 setup. Also I've been told you can purchase the S-Works fork seperately, at least that's what the Specialized shop at Newcastle told me, so if I can I'm going to buy one of those too.
Dude did u give any thought to just buying the frame and fitting it out yourself? I'm always hearing of people wanting to change the parts on there new bikes.
I wanted something to ride straight away, so I'm looking at replacing parts/swapping things out over the next 12 months. Also I'm using the parts off my new bike to upgrade my wife's bike, so all in all they way I'm doing suits me and my budget.
With regard to switching from a 2X10 to a 3X10...what would have to be changed on the component side of things....would I just have to change the front chainwheels and crank on the XTR set-up?
I am lucky as everything was dialed just right out of the shop (Manly Cycles) and the only thing i will now do is take it down for one of its free basic services to tighten everything up and make sure the brain at both ends is still dialed correctly. I guess if you always planned to change things then go for it but 3 months really isn't long enough to get a feel for something that is quite different to what you had been used to - bigger wheels, different sized chain rings and 2x10. This especially so if not riding very much.
The only thing that I planned on changing was to get some carbon Rovals (any other recommendations for 29er carbon race wheels??) and keep the stock wheels (which are great) for training and leisure.
@daveh I'm satisifed with my decision re changing over to a 3 x 10 set up, IMHO it provides greater gear changing flexibility. I should add with my current large chain ring I also run out of gears when riding hard, so a triple set up will sort this out for me as well. As for the Brain Shock, having had one for a few years now I'm pretty happy with the way I have that set up and I also like the idea of having it in the front fork, however, the adjustment lever/screw needs to be at the top of the fork for me, hence why I'd like to buy the S-Works fork if I can. All in all with changing things over it's still working out cheaper for me to have bought the Comp rather than the Expert, with the exception of adding the S-Works fork, which may or mey not happen.
As for wheels, I've only heard good things about the Rovals and I think it's always good to have a couple of sets, one for bashing about the place and another for when you want to get serious. This said, I'm a big Shimano fan and if they bring out a set of 29er XTR wheels they would be the one's I'd go for.
I would say that the adjustment at the bottom of the fork is the only thing that annoys me a little so it would be useful to have it at the top! I have also run out of gears when going hard downhill in a race but have learnt to deal with that so hear you there.
I felt the same way regarding the Expert/S-Works, far cheaper for to go for the Expert as it had just about everything I was after, and then just buy a new set of wheels. That's the great thing about bikes being component-ised, you can replace bits and pieces and end up with a ride that's just perfect for you.
One thing I am sure you will agree on and that is that the Epic 29er is a rocket, just an awesome bike to ride and it just wants to go fast. Fantastic race bike that can handle a bit of rough stuff as well!
@daveh The Epic is fantastic. Because I already owned a Epic 26er when I first starting looking to buy a 29er, which came about after riding a mate's bike, I test rode everything but the Epic 29er. In fact I was just about to buy a Trek when for some reason I thought I might as well take the 29er Epic for a test ride. Well you know what it's like, spend 5 mins on the bike and you want it there and then, anyway I kept the test bike for a couple of days and hit all my local tracks and pretty much bought one straight away, they are great bikes.