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Discussion Starter · #1 ·
I'm still trying to figure out the gearing for a 29"er. On the trail, my ride quality is great. It does not feel sluggish. On the road, If I could ride with my eyes closed, I would swear I was pushing a couch uphill. The thing is just plain sluggish. Wondering if it's my gearing, or just the additional rotational weight. Also, with the stock rings up front(in big ring), there does not seem to be a median between too hard and too easy. I'm thinking about swapping the cassette...running a 11-34 right now.

Question is: is it standard practice to run a tighter range cassette? Smaller rings up front? Ride more?
 

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Team Velveeta™
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have you tried some road rubber?

brewdog said:
On the trail, my ride quality is great. It does not feel sluggish.
Good deal. Since it's a mountain bike, that's where you'll want the gearing optimal.
brewdog said:
On the road, If I could ride with my eyes closed, I would swear I was pushing a couch uphill. The thing is just plain sluggish. Wondering if it's my gearing, or just the additional rotational weight.
Could be a little of both. Are you expecting it to feel like a road bike? Sluggish as in, gearing too high? Or not responsive?
brewdog said:
Also, with the stock rings up front(in big ring), there does not seem to be a median between too hard and too easy.
What ring sizes are you running?

I'm running 22-32-44 rings, and a 12-32 (8-speed) cluster. I may go back to a 42 big ring, because of the same thing you're talking about. I can only really use a couple gears in my biggie, unless it's downhill with a tailwind. I rarely use the big offroad, so it's not a big deal to me. And I'm just riding the pavement to get to dirt. Road performance doesn't need to be optimal.

I don't think you're using the wrong cluster. I may go to a SRAM 9-speed setup, mainly to get a 34. But other than having a low that isn't *quite* low enough and having too many high gears, I'm pretty happy with my bigwheel's gearing. When I was riding baby wheel bikes, I typically used either 22-32-42 with an XT 11-30 (8 spd), or 24-34-44 with 12-32. I've always been pretty happy with that kind of gearing. Going to microdrive rings with 12-32 has gotten me almost the same effective ratios, just maybe a hair higher across the board.

Slap some 700x25 tires on, then see how the road gearing feels. Probably still sluggish compared to a true road bike, but thank goodness it isn't a road bike when you're offroad, eh?
 

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Recovering couch patato
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Sometimes seating position makes a bike sluggish. Ever try to slide your seat fwd/aft? If you have one specific cadance you like on the road, it may well be your "new gearbox" is just too low or too high to match that with your present fitness. If so, gear down or indeed ride more! :)
Good luck, if you find a solution, please share it with us!
 

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Personally I have always been of the school of thought that if you are going to have gears, why not have the widest range possible? One time I set up a bike with 42 spds and had a range from an 11" low to a 126" high. That was a bit of overkill for sure. Now I run a 23"/118" range in 18 spds, but would like to have a bit lower gear for spinning some of the climbs here....I think an 18" low would be perfect as a bailout gear and I like having the high gear for wailing down the highway whenever the opportunity arises.

For some reason I have never felt sluggish on the road riding a 29"er, in fact just the opposite in fact, and don't ever run over 30 lbs. pressure either? So I don't know what to tell you there. I do run 170 cranks which are easier to spin with though.
 

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Discussion Starter · #5 ·
I'm not looking for the road bike feel, just expected a little more responsiveness. There's no *snap* when it somes to acceleration. I'm running Nano's on both my 26" and 29" so there's not much rolling resistance on either bike. The 29" just feels more sluggish than the 26". I've done the local rides on the KM but just can't hang as well as when I'm on 26". I'm running a 22-32-44, 11-34 w/ 180mm's
I raised my seat about 1" which helped some of the leg fatigue...maybe I'll move the saddle forward as recommended.
As for gear inches...never even considered trying to figure all of that out. I'm going to check into a 42t.
Being in Houston, I'm in the BR most of the time...don't really need the 34t, had that cassette already. Maybe I'll test a 12-27t off the X bike and spend more time in the middle ring.

Thanks for the info.




.
 

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Gear inch calcs are easy, front chainring divided by rear chainring times wheel diameter. If you spend most of your time in the larger gears perhaps some shorter cranks would help as you are not as much about torque and more about keeping the R's up?
 

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Gearing on a 29 is not much different than a 26

Basically on a 29" the gears are all shifted by one. So a 22/34 on a 29" is the
same as 22/32 on a 26". Since the grears are 10% taller on the 29" and most
cassettes are about 10% different between gears. www.sheldonbrown.com
gear calculator will do gear gain (takes into account your crank length.)

So on a 29", it is like being on a 26" that simply won't shift into 22/34 and sticks
in 22/32.

I would think getting spinning weight down on the 29" would help the most ... tubeless
tires? If a 29" has a disadvantage it is the heavier wheel sets. I notice on the flat
I appear to ride faster than 26" riders, but weenies on 700c "comfort bikes" cruise
along pretty well. The rolling resistance can start to add up in terms of power
demands even on the flat. Which comes down to how much power you can
generate long term, and is it put into overcoming rolling resistance or air resistance.

I have also looked at "power" to ride up say a 10% grade at some fixed cadence
on both a 26" and a 29" inch and it looks to me that also is around a 10% difference
(overcome gravity, rolling resistance, wind resistance). Now remember strength
does not necessarily scale with size.

I can't explain this, but it seems technique really helps on a 29"???? Getting low
on climbs and kissing the handlebars really helps. But I am new to this off-road thing,
so maybe I discovered how bad my technique really was ;)

-r
 

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Beware of Doggerel
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some ideas

Drop two teeth on the front and you should be reasonably close to 26er gearing. I run 20t granny and a 30t middle. I mainly ride in the middle, going to the granny on steep or sustained climbs and only using the big ring, 42t, once in a while. I prefer seated climbing and spinning so the granny gets a fair amount of use, but with the 29er momentum thing you can stay in the middle much longer once you get the gearing right. I run 11-32 in the back, because I don't like the big jump to the 34 tooth cog. Also with a 20t granny I have plenty of gears if I need them.

Also go with compact 5 arm cranks as you will have more gearing choices. I thought about going to 4 arm cranks but when I looked around for chainrings I could not find what I wanted.
Adam
 

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29er gearing

There's been a lot of discussion about gearing. Back on 7-19-04 there was a post titled Gearing 101 on a Karate Monkey and back on 6-18-04 there was a post titled 29er gearing where somone had an interesting graph concerning gearing. My solution as stated in these post has been a 20/30/42 Salsa front rings with a Raceface 5 arm crank with a 12/32 rear cassette. No problems, no chainsuck, perfect gearing for me and the local terrain and 27 useful gears. Can be an issue with chainstay clearence on some bikes on the front derrailleur. It may be lot of people trying different things to rid themselves of the slugishness try to mix and match chainrings without the proper relationships to each other, may be why some have so many headaches.
 

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I run standard XTR with 46t big ring. In the back I run a 34t biggest cog. There are no issues, if I want it to be easier to pedal, I shift. If I want it to be harder to pedal, I shift. I never run out of gears going either way....
 

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It's up to the rider

This discussion has been run around again and again and the reality is there is no concensus. Each of us have different styles and unless we race or play on the same trails, there is no way to compare what works best for us and in our area. Each of us has to tinker with the gearing until we are happy with what we ride. If your capable of running a 46/34/24, or any mixture of gears for that matter, in how you play or race and if your satisied with your how you feel after you play and how you feel and your placing after the finish than "run what you brung". If your not play around to see what works best for you.

For me I started winning again on the terrain I race when I more closely matched the 44/32/22 set up on a 26. That being a 42/30/20. The sluggishness with the big gearing killed me, never got to use the big ring the way I wanted, found I was tired because at times I didn't have enough granny, found I was loosing ground at the end of the race because I expended to much energy try do push too big of gears during the race and found myself restricted in the gearing available. Once I found what worked for me the sluggishness went away away and I found my endurance once again. The result was, for me, I began to win again.

Go play with your gearing, play alot and see what works best for you. That's the reason there's so many gears available. We're all different so find what your happy with. Your the one that's got to ride with it.
 

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gearing...

You have the correct gearing... you should try 170mm cranks. With the added rotational weight of the big wheel, a standard 175mm is going to make it tougher to spin. It's really quite simple: your standard LBS 26" (kids) bike has 175mm cranks to push a smaller diameter wheel, so why use the same crank length with a larger, heavier wheel? This concept makes perfect sense and after trying it, I'll never go back to 175. There are other benefits as well. It allows faster revolutions (ala Lance) and keeps your hips a bit quieter which has helped with low back pain. This was recommended to me by Wes Williams, the inventor of the big wheel MTB.

As a matter of fact, I have a perfect set of 170 black Race Face cranks and a BB you can have for cheap if you want to try. I just upgraded to the new XTR cranks.

Cheers,
James
 
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