Single speed cranks?



I'm after a 39T single speed crankset to go with my Nexus Inter8 hub
the LBS is building up for me. They offered the Shimano recommended
crankset (@$170) which includes outboard bearings. I'm somewhat of a
luddite (I've only just installed a cartridge bottom bracket to trial)
and apart from the excessive cost I just don't like the sound of this
newfangled outboard bearing nonsense.

Can anyone advise me of some plain-Jane square taper 170mm single
speed cranks preferably with a 39T chainring? Doesn't have to be
online, but online is ok, a brand name that I can give to the LBS
would do (though they are very much like the Soup Nazi (http://
en.wikipedia.org/wiki/Soup_Nazi) in there so I'm almost afraid to ask).
 
On 2007-10-29, [email protected] <[email protected]> wrote:
> I'm after a 39T single speed crankset to go with my Nexus Inter8 hub
> the LBS is building up for me. They offered the Shimano recommended
> crankset (@$170) which includes outboard bearings. I'm somewhat of a
> luddite (I've only just installed a cartridge bottom bracket to trial)
> and apart from the excessive cost I just don't like the sound of this
> newfangled outboard bearing nonsense.
>
> Can anyone advise me of some plain-Jane square taper 170mm single
> speed cranks preferably with a 39T chainring? Doesn't have to be
> online, but online is ok, a brand name that I can give to the LBS
> would do (though they are very much like the Soup Nazi (http://
> en.wikipedia.org/wiki/Soup_Nazi) in there so I'm almost afraid to ask).


Any old road cranks with replacable chainrings can be converted to SS
easily. These are easy to find (your local bicycle recycle place will
certainly have some). All you'll need then is a set of short chainring
bolts and an appropriate chain ring.

Cheers

Joel

--
Human Powered Cycles | High quality servicing and repairs
[email protected] | Affordable second hand bikes
(03) 9029 6504 | Bicycle reuse centre
www.humanpowered.com.au | Mechanical and on-road training and instruction
 
lemmiwinks wrote:
> Can anyone advise me of some plain-Jane square taper 170mm single
> speed cranks preferably with a 39T chainring?


I'll have a look in my "crank box" on the weekend...


BTH
 
On Oct 29, 3:41 pm, BT Humble <[email protected]> wrote:
> lemmiwinks wrote:
> > Can anyone advise me of some plain-Jane square taper 170mm single
> > speed cranks preferably with a 39T chainring?

>
> I'll have a look in my "crank box" on the weekend...
>
> BTH


Ta. I just realised I've got some worn out Shimano Biopace cranks
that could be pressed into service except the biopace rings are
elliptical (only the middle ring is worn out) so probably not good for
hub gears. I tried to get a replacement chainring from the LBS when
it wore out but they baffled me with BCD figures and generally didn't
want to help (I still consider this preferable to the thinly veiled
hostility they normally exhibit).
 
[email protected] wrote:

> Ta. I just realised I've got some worn out Shimano Biopace
> cranks that could be pressed into service except the biopace
> rings are elliptical (only the middle ring is worn out) so
> probably not good for hub gears. I tried to get a replacement
> chainring from the LBS when it wore out but they baffled me
> with BCD figures and generally didn't want to help (I still
> consider this preferable to the thinly veiled hostility they
> normally exhibit).


You need to know the BCD figure to be able to buy a chainring
which will fit. See
http://www.sheldonbrown.com/gloss_bo-z.html#bcd for info on how
to measure it.

Then you should be able to buy a round 39T chainwheel to fit
your cranks.

It'll be worth making sure you've got a bottom bracket of the
right length to get "perfect" chainline (no sideways
deflection, front to rear). In this respect, you'll be setting
the chainline up as if it were a single speed. See
http://www.sheldonbrown.com/chainline.html

John
 
On 2007-10-29, [email protected] (aka Bruce)
was almost, but not quite, entirely unlike tea:
> On Oct 29, 3:41 pm, BT Humble <[email protected]> wrote:
>> lemmiwinks wrote:
>> > Can anyone advise me of some plain-Jane square taper 170mm single
>> > speed cranks preferably with a 39T chainring?

>>
>> I'll have a look in my "crank box" on the weekend...

>
> Ta. I just realised I've got some worn out Shimano Biopace cranks
> that could be pressed into service except the biopace rings are
> elliptical (only the middle ring is worn out) so probably not good for
> hub gears.


Why not? The chainline stays under the same tension.

--
TimC
Can't open /usr/share/games/fortunes/fortunes. Lid stuck on cookie jar.
 
TimC wrote:

> Why not? The chainline stays under the same tension.


From my observation of Biopace chainrings in use, that's what I
thought too, but wasn't confident enough to say it.

Sheldon Brown does report using Biopace on a fixed-gear bike:
http://sheldonbrown.com/biopace.html

John
 
John Henderson wrote:
> TimC wrote:
> > Why not? The chainline stays under the same tension.

>
> From my observation of Biopace chainrings in use, that's what I
> thought too, but wasn't confident enough to say it.
>
> Sheldon Brown does report using Biopace on a fixed-gear bike:http://sheldonbrown.com/biopace.html


He certainly seems a bit of a "true believer" in Biopace chainrings.
The phrase "With all the zeal of a convert" springs to mind, for some
reason. ;-)

I'm sure they're very nice, mind you. Do you need to use a long-reach
front derailleur with them, or is varience in radius relatively small?


BTH
 
you'll need something at least vaguely built for the job.

Preferably running a tougher chain. IE track or BMX chain.
That means perferably a thicker toothed chainring. Anything less will struggle and possibly wear and/or snap

The Alfine chainset that the LBS is recommending is rather good and a steal at that price IMHO.
 
On Oct 29, 4:13 pm, John Henderson <[email protected]> wrote:
> [email protected] wrote:
> > Ta. I just realised I've got some worn out Shimano Biopace
> > cranks that could be pressed into service except the biopace
> > rings are elliptical (only the middle ring is worn out) so
> > probably not good for hub gears. I tried to get a replacement
> > chainring from the LBS when it wore out but they baffled me
> > with BCD figures and generally didn't want to help (I still
> > consider this preferable to the thinly veiled hostility they
> > normally exhibit).

>
> You need to know the BCD figure to be able to buy a chainring
> which will fit. Seehttp://www.sheldonbrown.com/gloss_bo-z.html#bcdfor info on how
> to measure it.
>
> Then you should be able to buy a round 39T chainwheel to fit
> your cranks.


I did some googling and turned up Sheldon's article on measuring BCD
but I haven't had a chance to check my chainrings as yet.

> It'll be worth making sure you've got a bottom bracket of the
> right length to get "perfect" chainline (no sideways
> deflection, front to rear). In this respect, you'll be setting
> the chainline up as if it were a single speed. Seehttp://www.sheldonbrown.com/chainline.html
>
> John


I'm slightly concerned about chainline as I just installed a cartridge
BB to try and it's 122mm. It's a roadbike but I'm currently running a
MTB triple. I figure if I need a shorter spindle length I'll buy a
new cartridge BB and put the 122mm in my MTB which is in pretty dire
need of either a rebuild of the cup and cone BB or a replacement.
 
On Oct 29, 7:15 pm, TimC <[email protected]
astro.swin.edu.au> wrote:
> On 2007-10-29, [email protected] (aka Bruce)
> was almost, but not quite, entirely unlike tea:
>
> > On Oct 29, 3:41 pm, BT Humble <[email protected]> wrote:
> >> lemmiwinks wrote:
> >> > Can anyone advise me of some plain-Jane square taper 170mm single
> >> > speed cranks preferably with a 39T chainring?

>
> >> I'll have a look in my "crank box" on the weekend...

>
> > Ta. I just realised I've got some worn out Shimano Biopace cranks
> > that could be pressed into service except the biopace rings are
> > elliptical (only the middle ring is worn out) so probably not good for
> > hub gears.

>
> Why not? The chainline stays under the same tension.


Does it? Ok, I'd assumed it wouldn't, but I'd not put much thought or
examination of the chainrings into that assumption.
 
On Oct 30, 6:37 am, John Henderson <[email protected]> wrote:
> TimC wrote:
> > Why not? The chainline stays under the same tension.

>
> From my observation of Biopace chainrings in use, that's what I
> thought too, but wasn't confident enough to say it.
>
> Sheldon Brown does report using Biopace on a fixed-gear bike:http://sheldonbrown.com/biopace.html
>
> John


The LBS told me that Biopace chainrings were no longer available when
I tried to get a new one about 18 months ago. However I'd just be
happy with a chainring that fits, biopace or not.
 
On Oct 30, 8:29 am, BT Humble <[email protected]> wrote:
> I'm sure they're very nice, mind you. Do you need to use a long-reach
> front derailleur with them, or is varience in radius relatively small?
>
> BTH


There was nothing fancy about the derailleur on the bike they came off
(that I noticed).
 
On Oct 29, 2:24 pm, Joel Mayes <[email protected]> wrote:

> Any old road cranks with replacable chainrings can be converted to SS
> easily. These are easy to find (your local bicycle recycle place will
> certainly have some). All you'll need then is a set of short chainring
> bolts and an appropriate chain ring.


The only bicycle recycle place is the shop at the tip (I got a nice
lugged steel roadie for $15) but it's probably worth checking out.
 
In aus.bicycle on Mon, 29 Oct 2007 22:37:42 -0000
[email protected] <[email protected]> wrote:
> The LBS told me that Biopace chainrings were no longer available when
> I tried to get a new one about 18 months ago. However I'd just be
> happy with a chainring that fits, biopace or not.


There's a lot of noise about "Q Rings" and "Rotor cranks" in the 'bent
world, both of which apparently do the same thing as biopace.

Zebee
 
On Oct 30, 9:57 am, Zebee Johnstone <[email protected]> wrote:
> In aus.bicycle on Mon, 29 Oct 2007 22:37:42 -0000
>
> [email protected] <[email protected]> wrote:
> > The LBS told me that Biopace chainrings were no longer available when
> > I tried to get a new one about 18 months ago. However I'd just be
> > happy with a chainring that fits, biopace or not.

>
> There's a lot of noise about "Q Rings" and "Rotor cranks" in the 'bent
> world, both of which apparently do the same thing as biopace.
>
> Zebee


I can imagine how well enquiries about anything remotely 'bent related
would be received at my LBS!
 
On 2007-10-29, [email protected] (aka Bruce)
was almost, but not quite, entirely unlike tea:
> On Oct 30, 9:57 am, Zebee Johnstone <[email protected]> wrote:
>> In aus.bicycle on Mon, 29 Oct 2007 22:37:42 -0000
>>
>> [email protected] <[email protected]> wrote:
>> > The LBS told me that Biopace chainrings were no longer available when
>> > I tried to get a new one about 18 months ago. However I'd just be
>> > happy with a chainring that fits, biopace or not.

>>
>> There's a lot of noise about "Q Rings" and "Rotor cranks" in the 'bent
>> world, both of which apparently do the same thing as biopace.

>
> I can imagine how well enquiries about anything remotely 'bent related
> would be received at my LBS!


"And when you're done choosing that, come over to our stand here where
we have a lovely display of beards"?

--
TimC
I don't want Perl to be beautiful -- I want you to write
beautiful programs in Perl. --Larry Wall
 
On Oct 30, 8:57 am, flyingdutch <flyingdutch.2z8...@no-
mx.forums.cyclingforums.com> wrote:
> you'll need something at least vaguely built for the job.
>
> Preferably running a tougher chain. IE track or BMX chain.
> That means perferably a thicker toothed chainring. Anything less will
> struggle and possibly wear and/or snap


Once I measure my BCD I can see what the LBS has in stock. I'm
breaking with tradition and not buying a Huffy chain from Kmart, so
the LBS will provide chain.

> The Alfine chainset that the LBS is recommending is rather good and a
> steal at that price IMHO.


Now *that* is a surprise! I don't want to change my BB though.
 
TimC wrote:
> On 2007-10-29, [email protected] (aka Bruce)
> > I can imagine how well enquiries about anything remotely 'bent related
> > would be received at my LBS!

>
> "And when you're done choosing that, come over to our stand here where
> we have a lovely display of beards"?


"No, no beards. But I'll have two stones with points, a big flat one,
and a packet of gravel."


BTH
 
On Oct 30, 11:37 am, TimC <[email protected]
astro.swin.edu.au> wrote:
> On 2007-10-29, [email protected] (aka Bruce)
> was almost, but not quite, entirely unlike tea:
>
> > I can imagine how well enquiries about anything remotely 'bent related
> > would be received at my LBS!

>
> "And when you're done choosing that, come over to our stand here where
> we have a lovely display of beards"?
>
> --
> TimC
> I don't want Perl to be beautiful -- I want you to write
> beautiful programs in Perl. --Larry Wall


I'd spend more money there if that was their attitude. Fortunately
there's plenty of online shopping :)