# Dual chainring, no derailluer, singlespeed?



## brokenchain (Jul 17, 2005)

I have some parts laying around and was thinking maybe i could build a single speed to try on the smoother trails around here. My question is can I run two rings up front with a single in the rear if I use a chain tensioner. I dont think that I have the endurance to pedal a 2:1 ratio yet so I am hoping that I could run this dual ring set up without a derailluer and just set it where I need it depending on the trail. I have a like new rockshox revelation, a set of BB7's, and a set of race face evolve DH cranks to use for a buildup so all I need is SS wheels, rear gear, chain, and a SS frame. Pricepoint has the redline monocog frame and fork for $160. 

What do you guys think?

Thanks, John


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## mattmor (Feb 15, 2004)

*2x2*

John,

I don't know if what you want to do will work. What I have seen people do is 2x2. Example - 32 and 36 up front, and 20 and 16 in the back. This was on a 29'er. But it gave him a good ratio to ride to the trails and a good trail ratio as well. As long as you keep the same number of teeth front to back you'll keep the same tension. Not sure if this helps you or not but something to consider.

Matt



brokenchain said:


> I have some parts laying around and was thinking maybe i could build a single speed to try on the smoother trails around here. My question is can I run two rings up front with a single in the rear if I use a chain tensioner. I dont think that I have the endurance to pedal a 2:1 ratio yet so I am hoping that I could run this dual ring set up without a derailluer and just set it where I need it depending on the trail. I have a like new rockshox revelation, a set of BB7's, and a set of race face evolve DH cranks to use for a buildup so all I need is SS wheels, rear gear, chain, and a SS frame. Pricepoint has the redline monocog frame and fork for $160.
> 
> What do you guys think?
> 
> Thanks, John


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## G-Cracker (Feb 8, 2006)

Just because 2:1 is thrown around a lot doesn't mean it's the end-all. Just find a ratio that you're comfortable with and as you get stronger, work yourself up to a 2:1 ratio. Good luck.


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## CB2 (May 7, 2006)

Depending on the jump from chainrings, I'd say you'd be better off using an old dérailleur than a tensioner to take up the slack.


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## bassteban (Jun 16, 2007)

*I'm confused*



mattmor said:


> John,
> 
> I don't know if what you want to do will work. What I have seen people do is 2x2. Example - 32 and 36 up front, and 20 and 16 in the back. This was on a 29'er. But it gave him a good ratio to ride to the trails and a good trail ratio as well. As long as you keep the same number of teeth front to back you'll keep the same tension. Not sure if this helps you or not but something to consider.
> 
> Matt


So w/this setup, do you run the lower gear on the climb(s)& stop & throw the chain onto the higher ratio for the descents?

I have an old friend who used to run a triple in front w/a bmx freewheel & rear derailleur(no r. shifter or cables to keep the chain tension).


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## eltazar (Nov 1, 2006)

I have 2 ring front / geared rear setup on my hardtail, without front der, or a chainguide, just an outer bash guard. Works well, it's just i barely use the smaller ring .


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## floibex (Feb 7, 2004)

... i run a 40/33:17 setup, paul melvin for tension and "shifting" by ball of the foot. i have a lot of flat roads 'til i'm able to hit dirt...



ciao
flo


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## bassteban (Jun 16, 2007)

OK, I'm still lost(happens all the time, don't mind me). Do you guys stop, loosen the rear wheel, change gears, readjust brakes, etc, or just(ball-of-foot)kick it over into the appropro gear?


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## thebigred67 (Mar 29, 2005)

Or you could just stop using your shifters. Find a gear that works and stay there. For me a big part of SS is losing a the extra stuff on the bars and the bike. It feels like riding a big bmx bike.


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## bassteban (Jun 16, 2007)

On my one speed, there will be no shifters. There will be one speed. There will be one chainring & one freewheel. What I'm not getting is how 2 chainrings & 2 rear cogs work w/o pulling over & wrenching on the bike, thus disrupting the oh-so-hard-to-come-by(for me)'flow'. Am I as dumb as I think I am, or actually dumber?


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## norm (Feb 20, 2005)

bassteban said:


> Do you guys stop, loosen the rear wheel, change gears, readjust brakes, etc,


Yeah, thats what i do....i commute on a 38X16 and ride trails on 34X20. works for me.:thumbsup: its a bit of a pain moving the chain from chainring to chainring, but it takes only a minute.


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## brokenchain (Jul 17, 2005)

So some of you run 2 in front and 2 in the rear with some kind of freewheel like this http://sheldonbrown.com/harris/white-freewheels.html

So if you space your rear sprokets the same distance apart as your front the your chainline will be ok. Also, the key to not having to use a tensioner is to keep the total tooth count the same fot both gear combos.

There are three reasons I am curious about this setup. First, not all trails are the same so it would be cool to have a more versitile setup without having to swap gears before I leave home. Second, I allready have a nice crank setup that I would like to use. Third, I just dont have the endurance yet to pull a big gear all of the time for every trail.

How small do middle rings come?

John


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## henrypennry (May 18, 2006)

I think all this sounds way too complicated. Singlespeeding for me goes like this:
1. Crap...I'm slowing down
2. Get butt of the seat and pedal harder
3. Really mash it
4. Still slowing down, jump off
5. Walk

The second (or maybe the 3rd or 4th) time you do the same trail you will find you can start eliminating #5, the 5th time maybe #4 and so on. That's why I like it...I get honest feedback on my progress. And I swear, maybe because of the straight chainline, lighter weight, or whatever, I always feel faster on my SS than on my geared bike.


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## Flat Ark (Oct 14, 2006)

Instead of running 2 chain rings up front, why not run a 1X9 set up. One ring up front and a cassette in the rear. Even with only 2 gears it is not really single speeding so why not just use 9.


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## brokenchain (Jul 17, 2005)

It would be nice to get rid of the derailluers front and rear.
Save weight too.
John


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## zziggy13 (Mar 13, 2004)

I just moved back to NYC and use a Paul Melvin with 44/32 on the front and a 18 on the back. I use the 44/18 to ride to the trails/in the city and the 32/18 to ride on the trails. Manually shift the chain when I need to switch gears.


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## brokenchain (Jul 17, 2005)

Do you have horizontal or vertical dropouts?
I am thinking about the Redline Monocog frame it has horizontal dropouts. Would the paul melvin work with horizontal dropouts.

How does it effect your chainline when you change back and forth?

John


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## Cygnus (Jan 7, 2004)

*my 2 x 2*

i commute on a 2x2 singlespeed. i built this bike from a frame with horizontal dropouts with the intent of maintaining a perfect chainline. yes, i stop, loosen the rear wheel, slip the chain inboard or outboard, retighten chain. it takes about 15-30 sec., tops. 42x16 for cruising, 36x22 for a monster climb. all on the road. = number of teeth in each gear combo means the same length of chain. i have another true 1x1 for the dirt. but this approach could be used for a 2x2 designed for riding to a trail, then going singletrack into the mountians.


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## brokenchain (Jul 17, 2005)

Did you use a regular freehub body and spacers to get your rear gears spaced correctly.
John


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## LWright (Jan 29, 2006)

I too run a Melvin with two frt rings, 34 and 24 with a 17 in the back. struggle up hill till I stop then by hand I roll the chain down onto the granny, get back on and grind it out. reach the top, while I catch my breath I roll it back up to the 34. The Melvin has a floating pulley that allows for the difference in chainline. when I do manage to "flow" I just keep on the 34. Did I mention this is on a duel suspension?


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## Cygnus (Jan 7, 2004)

*yes, xt*



brokenchain said:


> Did you use a regular freehub body and spacers to get your rear gears spaced correctly.
> John


yes, it's just an xt hub with spacers. those are both surly cogs. pretty easy to set up. nice having a quick release for rapid change, and also a chain tug (on the drive side) to keep the wheel in place and to quickly realign the wheel after moving the chain.


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## brokenchain (Jul 17, 2005)

How about putting a monocog flight derailleur hanger on the regular monocog frame. It would change the dropout to vertical on the drive side ( http://www.excelsports.com/new.asp?...ur+Dropout&vendorCode=REDLINE&major=6&minor=8 ) and make the wheelbase slightly longer. But the non drive side would still be horizontal and that wouldnt work.
Man, if the monocog could be fitted with dropouts like the santa cruz chameleon it would work perfect.

John


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## nogearshere (Mar 7, 2005)

i have a 42/16 32/19 double single...the two ratios works great. two master links in the chain, drop QR wheel remove (or add) links necessary, return wheel, ride. just so happens no tensioning or wheel moving required.

now i cant speak for 'purity' or 'oneness' or the inverse relationship of pie and marbles, but it works for me. particularly when i have a long way to go and a short time to get there.


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## brokenchain (Jul 17, 2005)

yea i can see how that works. i allready use sram powerlinks in my chains. just figure out where to add another and take the chain apart and put the extra section in my seat bag. 
thats a pretty good idea.

thanks, john


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## zziggy13 (Mar 13, 2004)

I have vertical dropouts, the Melvin is designed to handle up to a 14 tooth differential in between the front chainrings. The Melvin compensates for the differing chainlines and angles. Horizontal dropoouts, should be fine, if there is a derailluer hanger.

It is really simple to change gears, I ride on the street on the big gear and change to the smaller gear for the trails. I pick up the chain and move it to the gear I need.


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## Feclar (Apr 30, 2006)

Soooo does the Paul Melvin thingy ( http://www.webcyclery.com/product.php?productid=16382 ) work with a stock monocog 29er? (minus gears of course)

This would be a very very nice solution for me

Currently have 1 x 2 and I dont like having to wrench on the bike to change the gear, reaching down and manually doing it for a 2 x 1 would be most excellent


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