Converting my CX
#1
Newbie
Thread Starter
Join Date: Jan 2020
Posts: 3
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 1 Post(s)
Likes: 0
Liked 0 Times
in
0 Posts
Converting my CX
Hi everyone!
In the last month i went riding a few times whit fixie guys, and got immediatly hooked with the community and the bikes.
So i decided to convert my CX bike, which i'm not using anymore since i stopped doing that kind of races, in a fixed gear.
The first problem is the rear wheel: i saw a site that sells an adaptor that you put in the place of the cassette, it makes the wheel fixed and spaces the the pinion correctly (or at least that's what the site says).
Since the bike has vertical dropouts, I looked as well for a chain tensioner, and found one that consists of a piece of metal and a pulley, and is bolted where now there is the group.
I haven't found something to convert the double chainring to a single one, if you have any suggestions please tell me.
Anyway, you think those changes will be functional and safe? Thanks
In the last month i went riding a few times whit fixie guys, and got immediatly hooked with the community and the bikes.
So i decided to convert my CX bike, which i'm not using anymore since i stopped doing that kind of races, in a fixed gear.
The first problem is the rear wheel: i saw a site that sells an adaptor that you put in the place of the cassette, it makes the wheel fixed and spaces the the pinion correctly (or at least that's what the site says).
Since the bike has vertical dropouts, I looked as well for a chain tensioner, and found one that consists of a piece of metal and a pulley, and is bolted where now there is the group.
I haven't found something to convert the double chainring to a single one, if you have any suggestions please tell me.
Anyway, you think those changes will be functional and safe? Thanks
#2
Senior Member
Join Date: Sep 2009
Location: PHL
Posts: 9,948
Bikes: Litespeed Catalyst, IRO Rob Roy, All City Big Block
Mentioned: 19 Post(s)
Tagged: 0 Thread(s)
Quoted: 1332 Post(s)
Liked 398 Times
in
194 Posts
There's no safe way to use a chain tensioner on a fixed gear. You'll probably need an eccentric bottom bracket or hub if you want to use a frame with vertical dropouts.
#3
Senior Member
Join Date: Nov 2010
Posts: 3,504
Mentioned: 9 Post(s)
Tagged: 0 Thread(s)
Quoted: 586 Post(s)
Liked 612 Times
in
447 Posts
+1, don't do it! Only use a tensioner for single speed drive-trains and only with brakes. As for your cranks, you can remove the chain rings and install one of suitable size. Depending upon a lot of factors, you may need to install the ring on the inside of the crank spider to improve the chainline. If you use 3/8" chain it is a bit less important.
Look up "magic gear" on the search function. You "might" be lucky and find a combination that works with your dropouts. If you are set of using that frame, I would just spend some bucks and get an eccentric BB and a crank set designed for fixed gears.
Look up "magic gear" on the search function. You "might" be lucky and find a combination that works with your dropouts. If you are set of using that frame, I would just spend some bucks and get an eccentric BB and a crank set designed for fixed gears.
#4
Newbie
Thread Starter
Join Date: Jan 2020
Posts: 3
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 1 Post(s)
Likes: 0
Liked 0 Times
in
0 Posts
thank you, i've "studied" a bit this topic and decided to build a single speed instead, i don't want to spend too much money. i'm going to use it in a flat city, but i also want to be able to go up climbs, also long ones...will 46x16 do the job? i'm 19 and pretty trained (i raced xc until last october, then i started university and rode a bit less)
#5
Senior Member
Join Date: Nov 2010
Posts: 3,504
Mentioned: 9 Post(s)
Tagged: 0 Thread(s)
Quoted: 586 Post(s)
Liked 612 Times
in
447 Posts
thank you, i've "studied" a bit this topic and decided to build a single speed instead, i don't want to spend too much money. i'm going to use it in a flat city, but i also want to be able to go up climbs, also long ones...will 46x16 do the job? i'm 19 and pretty trained (i raced xc until last october, then i started university and rode a bit less)
#6
Senior Member
Join Date: Jul 2002
Location: Sacramento, California, USA
Posts: 40,865
Bikes: Specialized Tarmac, Canyon Exceed, Specialized Transition, Ellsworth Roots, Ridley Excalibur
Mentioned: 68 Post(s)
Tagged: 0 Thread(s)
Quoted: 2952 Post(s)
Liked 3,106 Times
in
1,417 Posts
46x16 is a pretty big gear, especially if you keep the knobbies.
#7
Senior Member
Join Date: Sep 2009
Location: PHL
Posts: 9,948
Bikes: Litespeed Catalyst, IRO Rob Roy, All City Big Block
Mentioned: 19 Post(s)
Tagged: 0 Thread(s)
Quoted: 1332 Post(s)
Liked 398 Times
in
194 Posts
^^ Yup. A good way to figure this out is to just go for bike ride with only one gear. Find one where you can accelerate pretty well from standstill, maintain a good speed, and get up any climbs you encounter. Then try to replicate that with your single speed gearing.
As for what to do with the double, the easiest solution is to buy some single speed chainring bolts and just use one of the chainrings you have already, assuming your setup allows for it.
As for what to do with the double, the easiest solution is to buy some single speed chainring bolts and just use one of the chainrings you have already, assuming your setup allows for it.
Likes For seau grateau:
#8
working on my sandal tan
Join Date: Aug 2011
Location: CID
Posts: 22,627
Bikes: 1991 Bianchi Eros, 1964 Armstrong, 1988 Diamondback Ascent, 1988 Bianchi Premio, 1987 Bianchi Sport SX, 1980s Raleigh mixte (hers), All-City Space Horse (hers)
Mentioned: 98 Post(s)
Tagged: 0 Thread(s)
Quoted: 3870 Post(s)
Liked 2,563 Times
in
1,577 Posts
This gets repeated a lot around here, but is it true? Wouldn't most spring-loaded chain tensioners just retract when the lower run of chain goes taut?
#9
I am potato.
Join Date: Jun 2015
Location: Pacific Northwest
Posts: 3,104
Bikes: Only precision built, custom high performance elitist machines of the highest caliber. 🍆
Mentioned: 28 Post(s)
Tagged: 0 Thread(s)
Quoted: 1782 Post(s)
Liked 1,621 Times
in
927 Posts
With a single speed, It doesn't matter. The chain just freewheels backwards & the bike is stopped by actual brakes. With a fixie or a hub equiped with a coaster brake It'll work for the fraction of a second before the tensioner is pulled straight like a guitar string until the hanger gets ripped from the frame.
__________________
I shouldn't have to "make myself more visible;" Drivers should just stop running people over.
Car dependency is a tax.
I shouldn't have to "make myself more visible;" Drivers should just stop running people over.
Car dependency is a tax.
#10
working on my sandal tan
Join Date: Aug 2011
Location: CID
Posts: 22,627
Bikes: 1991 Bianchi Eros, 1964 Armstrong, 1988 Diamondback Ascent, 1988 Bianchi Premio, 1987 Bianchi Sport SX, 1980s Raleigh mixte (hers), All-City Space Horse (hers)
Mentioned: 98 Post(s)
Tagged: 0 Thread(s)
Quoted: 3870 Post(s)
Liked 2,563 Times
in
1,577 Posts
With a single speed, It doesn't matter. The chain just freewheels backwards & the bike is stopped by actual brakes. With a fixie or a hub equiped with a coaster brake It'll work for the fraction of a second before the tensioner is pulled straight like a guitar string until the hanger gets ripped from the frame.
#11
Senior Member
Join Date: Sep 2009
Location: PHL
Posts: 9,948
Bikes: Litespeed Catalyst, IRO Rob Roy, All City Big Block
Mentioned: 19 Post(s)
Tagged: 0 Thread(s)
Quoted: 1332 Post(s)
Liked 398 Times
in
194 Posts
Putting aside that possibility, it's still not safely functional. Any time you stop putting enough force into the drivetrain to keep the chain taut, all the slack your tensioner was taking up is suddenly introduced back into your drivetrain. There's no good time for that to happen.
Likes For seau grateau:
#12
Senior Member
Join Date: Dec 2019
Location: South Shore of Long Island
Posts: 2,785
Bikes: 2010 Carrera Volans, 2015 C-Dale Trail 2sl, 2017 Raleigh Rush Hour, 2017 Blue Proseccio, 1992 Giant Perigee, 80s Gitane Rallye Tandem
Mentioned: 12 Post(s)
Tagged: 0 Thread(s)
Quoted: 1079 Post(s)
Liked 1,017 Times
in
719 Posts
If you have a shimano or sram thru axle crank you can get a BB by Phil Wood or I believe Wheels Manufacturing which will function as an eccentric, it will not work with any square taper or 30mm axle. You can also get a white Industries eccentric hub with 135mm spacing that also solves the whole chain tension issue.
#13
I am potato.
Join Date: Jun 2015
Location: Pacific Northwest
Posts: 3,104
Bikes: Only precision built, custom high performance elitist machines of the highest caliber. 🍆
Mentioned: 28 Post(s)
Tagged: 0 Thread(s)
Quoted: 1782 Post(s)
Liked 1,621 Times
in
927 Posts
No, but just for giggles once I mounted a roller brake wheel into a derailleur equipped frame. It didn't take long to see where the folly lay.
__________________
I shouldn't have to "make myself more visible;" Drivers should just stop running people over.
Car dependency is a tax.
I shouldn't have to "make myself more visible;" Drivers should just stop running people over.
Car dependency is a tax.
#14
working on my sandal tan
Join Date: Aug 2011
Location: CID
Posts: 22,627
Bikes: 1991 Bianchi Eros, 1964 Armstrong, 1988 Diamondback Ascent, 1988 Bianchi Premio, 1987 Bianchi Sport SX, 1980s Raleigh mixte (hers), All-City Space Horse (hers)
Mentioned: 98 Post(s)
Tagged: 0 Thread(s)
Quoted: 3870 Post(s)
Liked 2,563 Times
in
1,577 Posts
Putting aside that possibility, it's still not safely functional. Any time you stop putting enough force into the drivetrain to keep the chain taut, all the slack your tensioner was taking up is suddenly introduced back into your drivetrain. There's no good time for that to happen.
But the whole "ripping off derailleur hangers" sounds like an old wives' tale. Provided a sprung chain tensioner has enough travel to allow the lower run of chain to pull straight, it should be out of the circuit at that point, posing no danger to itself or the hanger. Perhaps the warnings come from devices that are bolted into place and aren't able to move, so they bend under the chain tension, but I don't know why someone would choose that solution...
#15
Senior Member
Join Date: Nov 2010
Posts: 3,504
Mentioned: 9 Post(s)
Tagged: 0 Thread(s)
Quoted: 586 Post(s)
Liked 612 Times
in
447 Posts
^^ Yup. A good way to figure this out is to just go for bike ride with only one gear. Find one where you can accelerate pretty well from standstill, maintain a good speed, and get up any climbs you encounter. Then try to replicate that with your single speed gearing.
As for what to do with the double, the easiest solution is to buy some single speed chainring bolts and just use one of the chainrings you have already, assuming your setup allows for it.
As for what to do with the double, the easiest solution is to buy some single speed chainring bolts and just use one of the chainrings you have already, assuming your setup allows for it.
This is some of the best advice I've read on these forums. I've heard it put simply this way, "If you want to know what it's like to ride a SS, just don't shift!".
#16
Newbie
Thread Starter
Join Date: Jan 2020
Posts: 3
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 1 Post(s)
Likes: 0
Liked 0 Times
in
0 Posts
Thank you all very much. In the end I think that for what I will do with the bike, ss is more functional than fixed, I'll play around with gears until I found the perfect one.
#17
Senior Member
Join Date: Jul 2002
Location: Sacramento, California, USA
Posts: 40,865
Bikes: Specialized Tarmac, Canyon Exceed, Specialized Transition, Ellsworth Roots, Ridley Excalibur
Mentioned: 68 Post(s)
Tagged: 0 Thread(s)
Quoted: 2952 Post(s)
Liked 3,106 Times
in
1,417 Posts
FWIW, single speed cross racing is a thing.
Likes For caloso: