2 questions: fixed gear chainline and rusty spokes....

[Alan Hoyle]

I bought a 80's Nishiki road bike converted to fixed gear off of eBay
on the cheap (<$150). I couldn't get a lockring installed on the
low-end Suzue hub myself (don't have the right tools) and brought it
into the LBS for them to do it. They got it set up, but told me my
chainline was off and I should get a shorter bottom bracket to make it
work better. Is there another way to handle this without spending the
money on a new BB? they said it was something on the order of 2.5 mm
off....

Also, the rear wheel was rebuilt with a fixed/free hub, but the front
seems to be original and the spokes have rust on them. Is it safe to
ride on this wheel? The rims themselves seem fine: they're aluminum
and don't seem to be in bad shape.

-alan

--
Alan Hoyle - [email protected] - http://www.alanhoyle.com/
"I don't want the world, I just want your half." -TMBG
Get Horizontal, Play Ultimate.

 

[Velo Psycho]

Can you space out the chainrings?

And how much could a new BB cost?

 

[Sheldon Brown]

Alan Hoyle wrote:

> I bought a 80's Nishiki road bike converted to fixed gear off of eBay
> on the cheap (<$150). I couldn't get a lockring installed on the
> low-end Suzue hub myself (don't have the right tools) and brought it
> into the LBS for them to do it. They got it set up, but told me my
> chainline was off and I should get a shorter bottom bracket to make it
> work better. Is there another way to handle this without spending the
> money on a new BB? they said it was something on the order of 2.5 mm
> off....

Yes, you can put spacer washers between the chainring and the crank
spider. See: http://harriscyclery.com/fixed.html#bolts and scroll down
a bit.

The spacer washers are the same ones used for rear hubs.

This isn't elegant but it's cheap and it works.

Sheldon "http://sheldonbrown.com/fixed" Brown
+---------------------------------------------------------------+
| The first duty of a revolutionary is to get away with it. |
| --Abbie Hoffman |
+---------------------------------------------------------------+
Harris Cyclery, West Newton, Massachusetts
Phone 617-244-9772 FAX 617-244-1041
http://harriscyclery.com
Hard-to-find parts shipped Worldwide
http://captainbike.com http://sheldonbrown.com

 

[Scott]

Alan Hoyle wrote:
> I bought a 80's Nishiki road bike converted to fixed gear off of eBay
> on the cheap (<$150). I couldn't get a lockring installed on the
> low-end Suzue hub myself (don't have the right tools) and brought it
> into the LBS for them to do it. They got it set up, but told me my
> chainline was off and I should get a shorter bottom bracket to make
it
> work better. Is there another way to handle this without spending
the
> money on a new BB? they said it was something on the order of 2.5 mm
> off....
>
> Also, the rear wheel was rebuilt with a fixed/free hub, but the front
> seems to be original and the spokes have rust on them. Is it safe to
> ride on this wheel? The rims themselves seem fine: they're aluminum
> and don't seem to be in bad shape.
>
> -alan
>
> --
> Alan Hoyle - [email protected] - http://www.alanhoyle.com/
> "I don't want the world, I just want your half." -TMBG
> Get Horizontal, Play Ultimate.

I'm assuming that since they told you you need a shorter BB spindle,
that your chainring is too far out to the right. I'm also assuming
that you must have the ring on the inner side of the crankarm, or else
you should just move the ring to the inside and slap the shop guy who
tried to sell you a BB.

If you already have the ring on the inside, and it's still too far to
the right, you could try moving the cog outward by using a spacer
between the cog and the hub. MUCH cheaper than a new BB.

 

[Phil, Squid-in-Training]

"Scott" <[email protected]> wrote in message
news:[email protected]...
>
> Alan Hoyle wrote:
>> I bought a 80's Nishiki road bike converted to fixed gear off of eBay
>> on the cheap (<$150). I couldn't get a lockring installed on the
>> low-end Suzue hub myself (don't have the right tools) and brought it
>> into the LBS for them to do it. They got it set up, but told me my
>> chainline was off and I should get a shorter bottom bracket to make
> it
>> work better. Is there another way to handle this without spending
> the
>> money on a new BB? they said it was something on the order of 2.5 mm
>> off....
>>
>> Also, the rear wheel was rebuilt with a fixed/free hub, but the front
>> seems to be original and the spokes have rust on them. Is it safe to
>> ride on this wheel? The rims themselves seem fine: they're aluminum
>> and don't seem to be in bad shape.
>>
>> -alan
>>
>> --
>> Alan Hoyle - [email protected] - http://www.alanhoyle.com/
>> "I don't want the world, I just want your half." -TMBG
>> Get Horizontal, Play Ultimate.
>
> I'm assuming that since they told you you need a shorter BB spindle,
> that your chainring is too far out to the right. I'm also assuming
> that you must have the ring on the inner side of the crankarm, or else
> you should just move the ring to the inside and slap the shop guy who
> tried to sell you a BB.
>
> If you already have the ring on the inside, and it's still too far to
> the right, you could try moving the cog outward by using a spacer
> between the cog and the hub. MUCH cheaper than a new BB.
>

That would reduce the number of threads engaged between the freewheel and
the hub. Whether or not it's a concern, I don't know, but I don't like the
sound of it.

--
Phil, Squid-in-Training

 

[Marcus Coles]

Alan Hoyle wrote:
> I bought a 80's Nishiki road bike converted to fixed gear off of eBay
> on the cheap (<$150). I couldn't get a lockring installed on the
> low-end Suzue hub myself (don't have the right tools) and brought it
> into the LBS for them to do it. They got it set up, but told me my
> chainline was off and I should get a shorter bottom bracket to make it
> work better. Is there another way to handle this without spending the
> money on a new BB? they said it was something on the order of 2.5 mm
> off....
>
> Also, the rear wheel was rebuilt with a fixed/free hub, but the front
> seems to be original and the spokes have rust on them. Is it safe to
> ride on this wheel? The rims themselves seem fine: they're aluminum
> and don't seem to be in bad shape.
>
> -alan
>

A real cheap fix that worked with my 1982 Nishiki which used a Sakae
crank and Kawahara labelled loose ball BB was to reverse the
asymmetrical bb axle and then put the ring in the outer position.

My legs could not tell the lack of symmetry and the chain line was
perfect with the Sanshin hubbed, respaced, de-dished wheel and Suntour
track cog.

Marcus

 

[m-gineering]

"Phil, Squid-in-Training" wrote:

> > If you already have the ring on the inside, and it's still too far to
> > the right, you could try moving the cog outward by using a spacer
> > between the cog and the hub. MUCH cheaper than a new BB.
> >
>
> That would reduce the number of threads engaged between the freewheel and
> the hub. Whether or not it's a concern, I don't know, but I don't like the
> sound of it.

Provbably the reverse actually. This will cover the thread runout on the
hub, which is useless anyhow. With cheap flat stamped cogs not using a
spacer is asking for stripped threads!
--
---
Marten Gerritsen

INFOapestaartjeM-GINEERINGpuntNL
www.m-gineering.nl

 

[m-gineering]

Sheldon Brown wrote:

>>..... I should get a shorter bottom bracket to make it
> > work better. Is there another way to handle this without spending the
> > money on a new BB? they said it was something on the order of 2.5 mm
> > off....
>
> Yes, you can put spacer washers between the chainring and the crank
> spider. The spacer washers are the same ones used for rear hubs.

> +---------------------------------------------------------------+
> | The first duty of a revolutionary is to get away with it. |
> | --Abbie Hoffman |
> +---------------------------------------------------------------+


Sorry Sheldon, but I can't let you get away with this! If the OP needs a
shorter axle spacing the bracket to the right won't work

--
---
Marten Gerritsen

INFOapestaartjeM-GINEERINGpuntNL
www.m-gineering.nl

 

[Luke]

In article <[email protected]>, Phil,
Squid-in-Training <[email protected]> wrote:

> > If you already have the ring on the inside, and it's still too far to
> > the right, you could try moving the cog outward by using a spacer
> > between the cog and the hub. MUCH cheaper than a new BB.
> >
>
> That would reduce the number of threads engaged between the freewheel and
> the hub. Whether or not it's a concern, I don't know, but I don't like the
> sound of it.

You're right to be wary. It may also preclude the installation of a
lockring.

luke

 

[Luke]

In article <[email protected]>, m-gineering
<[email protected]> wrote:

<Sheldon wrote>
> >
> > Yes, you can put spacer washers between the chainring and the crank
> > spider. The spacer washers are the same ones used for rear hubs.
>
<sig snip>
>
> Sorry Sheldon, but I can't let you get away with this! If the OP needs a
> shorter axle spacing the bracket to the right won't work

m, Sheldon's solution doesn't involving spacing the bottom bracket: the
spacers are installed between the chainring (on the inner side of the
spider flats) and the crank's spider itself. This will move the
chainring toward the non-drive side.

luke

 

[Cam]

Alan Hoyle wrote:
> I bought a 80's Nishiki road bike converted to fixed gear off of eBay
> on the cheap (<$150). I couldn't get a lockring installed on the
> low-end Suzue hub myself (don't have the right tools) and brought it
> into the LBS for them to do it. They got it set up, but told me my
> chainline was off and I should get a shorter bottom bracket to make
it
> work better. Is there another way to handle this without spending
the
> money on a new BB? they said it was something on the order of 2.5 mm
> off....
>

How important is it to get it perfect? Any derailler equipped bike
spends it's life bending the chain a lot more than 2.5 mm. I'm sure
chain wear and efficiency would improve, but how much?

Cam

 

[Sheldon Brown]

"Phil, Squid-in-Training" wrote:
>
>>>If you already have the ring on the inside, and it's still too far to
>>>the right, you could try moving the cog outward by using a spacer
>>>between the cog and the hub. MUCH cheaper than a new BB.
>>>
>>
>>That would reduce the number of threads engaged between the freewheel and
>>the hub. Whether or not it's a concern, I don't know, but I don't like the
>>sound of it.

Marten replied:

> Provbably the reverse actually. This will cover the thread runout on the
> hub, which is useless anyhow. With cheap flat stamped cogs not using a
> spacer is asking for stripped threads!

That's true as far as it goes, but I would shorten this last sentence thus:

"cheap flat stamped cogs...is asking for stripped threads!"

Sheldon "False Economy" Brown
+-----------------------------------------------------------+
| In my opinion two characteristics disqualify skating |
| as vehicular travel. |
| The first is the necessary side-to-side swerving motion. |
| The second is the very poor braking deceleration. |
| I think that skating should not be allowed on either |
| pedestrian or vehicular facilities. -- John Forester |
+-----------------------------------------------------------+
Harris Cyclery, West Newton, Massachusetts
Phone 617-244-9772 FAX 617-244-1041
http://harriscyclery.com
Hard-to-find parts shipped Worldwide
http://captainbike.com http://sheldonbrown.com

 

[Scott]

Luke wrote:
> In article <[email protected]>, Phil,
> Squid-in-Training <[email protected]> wrote:
>
> > > If you already have the ring on the inside, and it's still too
far to
> > > the right, you could try moving the cog outward by using a spacer
> > > between the cog and the hub. MUCH cheaper than a new BB.
> > >
> >
> > That would reduce the number of threads engaged between the
freewheel and
> > the hub. Whether or not it's a concern, I don't know, but I don't
like the
> > sound of it.
>
> You're right to be wary. It may also preclude the installation of a
> lockring.
>
> luke


Lock ring/schmock ring... I've ridden thousands of mile every winter
for the past 8 years, and have raced on the track for going on 6
seasons, and have never used a lockring, nor never needed one.

Why? Well, my wheels/cogs used on the track are quality enough that
when the cog is really torqued on, it's tight enough for even panic
stopping, and I wouldn't dream of riding a fixed gear on the road
without a front brake. With even reasonable torque on the cog, it's
next to impossible to spin off a cog in an emergency stop if you're
using the front brake.

In fact, I've tried to spin the cog off by rolling slowly, hopping the
rear wheel and applying backpressure when the wheel hits the ground.
Can't spin the damn thing off no matter how hard I try.

Can't imagine using a lockring.

 

[Fritz M]

Alan Hoyle wrote:

> they said it was something on the order of 2.5 mm off....

2.5 mm??

On my fixie I just eyeball the chainline. Is it really that important?

In fact, my spider's a little bent, causing my chaingring to wobble
laterally by at least 2.5mm, probably a little more. Should I be
concerned about that? I've never thrown the chain, but still...

RFM

 

[Alan Hoyle]

On 10 Feb 2005 22:22:18 GMT, Alan Hoyle wrote:

> [chainline]

Hey all, Thanks for the answers to this question, I placed an order
for spacers, etc. from Sheldon to fix the problem. However, that
still leaves me with the second part:

> ... the front seems to be original and the spokes have rust on them.
> Is it safe to ride on this wheel? The rims themselves seem fine:
> they're aluminum and don't seem to be in bad shape.

Is my front wheel safe? Are rusted spokes still strong?

-alan

--
Alan Hoyle - [email protected] - http://www.alanhoyle.com/
"I don't want the world, I just want your half." -TMBG
Get Horizontal, Play Ultimate.

 

[Sheldon Brown]

Alan Hoyle wrote:

> Hey all, Thanks for the answers to this question, I placed an order
> for spacers, etc. from Sheldon to fix the problem. However, that
> still leaves me with the second part:
>
>>... the front seems to be original and the spokes have rust on them.
>>Is it safe to ride on this wheel? The rims themselves seem fine:
>>they're aluminum and don't seem to be in bad shape.
>
> Is my front wheel safe? Are rusted spokes still strong?

Depends how badly rusted they are. The reason nobody has been answering
that part of your question is that we can't see the spokes from here!

It is very unsual to have any sort of problem with front spokes, most
front wheels are way overbuilt compared with rears.

Sheldon "Once Had To Get Rusted Busted Spokes Brazed Together On A Tour"
Brown
+----------------------------------------------------------+
| If only God would give me some clear sign! |
| Like making a large deposit in my name at a Swiss bank. |
| --Woody Allen |
+----------------------------------------------------------+
Harris Cyclery, West Newton, Massachusetts
Phone 617-244-9772 FAX 617-244-1041
http://harriscyclery.com
Hard-to-find parts shipped Worldwide
http://captainbike.com http://sheldonbrown.com

 

[Zog The Undeniable]

Phil, Squid-in-Training wrote:

> That would reduce the number of threads engaged between the freewheel and
> the hub. Whether or not it's a concern, I don't know, but I don't like the
> sound of it.
>
It works for me, although I'm getting a new hub and chainset anyway now
funds allow. I can get the lockring on - it depends on the hub.

 

[Zog The Undeniable]

Cam wrote:

> How important is it to get it perfect? Any derailler equipped bike
> spends it's life bending the chain a lot more than 2.5 mm. I'm sure
> chain wear and efficiency would improve, but how much?

Very important, especially for chains with bushings (as preferred by a
lot of track riders) which crackle horribly if the chainline isn't
within a millimetre.

 

[Philip Holman]

"Zog The Undeniable" <[email protected]> wrote in message
news:420d23b3.0@entanet...
> Cam wrote:
>
>> How important is it to get it perfect? Any derailler equipped bike
>> spends it's life bending the chain a lot more than 2.5 mm. I'm sure
>> chain wear and efficiency would improve, but how much?
>
> Very important, especially for chains with bushings (as preferred by a
> lot of track riders) which crackle horribly if the chainline isn't
> within a millimetre.

Not just for operational performance, throwing a chain from a standing
start at a traffic light can be dangerous. It's also easier to lose a
fixie chain through poor alignment than a derailleur which feeds the
chain onto the cog at the optimum position.

It's the BB flex that throws the chain on a fixie. This is highest from
a standing start and with the right pedal under load deflecting the BB
to the left and assisted by chain tension. If the chainring is 2.5mm
outboard of the cog, I would say this would be OK. It's a real problem
when its off in the other direction. BB deflection from left pedal load
is countered by chain tension.

I did a thorough investigation after losing my chain a few times on the
track and being told I must be pulling the rear wheel. Not so.

Phil H

 

[Marcus Coles]

Philip Holman wrote:
>
> Not just for operational performance, throwing a chain from a standing
> start at a traffic light can be dangerous. It's also easier to lose a
> fixie chain through poor alignment than a derailleur which feeds the
> chain onto the cog at the optimum position.
>
> It's the BB flex that throws the chain on a fixie. This is highest from
> a standing start and with the right pedal under load deflecting the BB
> to the left and assisted by chain tension. If the chainring is 2.5mm
> outboard of the cog, I would say this would be OK. It's a real problem
> when its off in the other direction. BB deflection from left pedal load
> is countered by chain tension.
>
> I did a thorough investigation after losing my chain a few times on the
> track and being told I must be pulling the rear wheel. Not so.
>

Phil,

It seems to me something else is going wrong in this case.

IME with a single speed a chain has to be very slack and out by a mile
to derail.

Chains really want to stay on.

The chain has to be moved over so far that the next tooth pushes the
side plate over and off the sprocket to derail.
When a BB flexes the sprocket moves over and normally just drags the
chain along with it.

On my track bike you'd have to pry like crazy to derail the chain. On my
road conversions it might be slightly easier as they use derailer
rings. Still I have never derailed the chain in use on a fixed or ss
and not all have been well aligned.
Also I am no light weight and put out a fair bit of power from a
standing start.

A derailer misaligns the chain directly adjacent to the gear not a foot
and a half away.
A derailer drivetrain also has a lightly tensioned flexible chain and
short and sometimes twisted gear teeth.

I think further investigation is in order.

Marcus