Converting freewheel hub to single speed, it ain't rocket science eh?



L

landotter

Guest
Penpal over in England is converting an old Peugeot to SS. He's a bike
noob, but mechanically at engineer level. I told him to take the rear
wheel to a shop and have them move the axle and get the rear wheel
"undished" in order to get the chainline right. The shop says that this
is "very difficult" and has sold him a bmx hub (110mm and I doubt they
respacered it) and a new rigida rim, plus are charging for a build.

Now I've "singled" a dozen or so bikes, both cassette hubs and
freewheel, and have no idea what they're going on about. Moving a hub
axle and undishing a wheel are extremely normal and basic
concepts--please tell me that I'm not loony for thinking that this kid
isn't getting his chain yanked?
 
landotter wrote:
> Penpal over in England is converting an old Peugeot to SS. He's a bike
> noob, but mechanically at engineer level. I told him to take the rear
> wheel to a shop and have them move the axle and get the rear wheel
> "undished" in order to get the chainline right. The shop says that this
> is "very difficult" and has sold him a bmx hub (110mm and I doubt they
> respacered it) and a new rigida rim, plus are charging for a build.
>
> Now I've "singled" a dozen or so bikes, both cassette hubs and
> freewheel, and have no idea what they're going on about. Moving a hub
> axle and undishing a wheel are extremely normal and basic
> concepts--please tell me that I'm not loony for thinking that this kid
> isn't getting his chain yanked?


Yep, they're yanking his chain, particularly the part about the BMX
hub. I built a single-speeder around an old Raliegh frame and a
threaded hub. I didn't even respace the hub to center the flanges. I
moved the chainring to the inside of the crank spider to get the
alignment close, but it's still a little off. It still works fine,
though. I suspect chainline is a little more critical with fixed-gear
bikes, but I have no data.

Jeff
 
landotter wrote:
> Penpal over in England is converting an old Peugeot to SS. He's a bike
> noob, but mechanically at engineer level. I told him to take the rear
> wheel to a shop and have them move the axle and get the rear wheel
> "undished" in order to get the chainline right. The shop says that this
> is "very difficult" and has sold him a bmx hub (110mm and I doubt they
> respacered it) and a new rigida rim, plus are charging for a build.
>
> Now I've "singled" a dozen or so bikes, both cassette hubs and
> freewheel, and have no idea what they're going on about. Moving a hub
> axle and undishing a wheel are extremely normal and basic
> concepts--please tell me that I'm not loony for thinking that this kid
> isn't getting his chain yanked?


>>>

The shop says that this is "very difficult" and has sold him a bmx hub
<<<

Trust me, that would only be 'very difficult' for a dumb Limey.
Fortunately
there are a few that are smarter than that. :)

Lewis

****
 
[email protected] wrote:
> landotter wrote:
> > Penpal over in England is converting an old Peugeot to SS. He's a bike
> > noob, but mechanically at engineer level. I told him to take the rear
> > wheel to a shop and have them move the axle and get the rear wheel
> > "undished" in order to get the chainline right. The shop says that this
> > is "very difficult" and has sold him a bmx hub (110mm and I doubt they
> > respacered it) and a new rigida rim, plus are charging for a build.
> >
> > Now I've "singled" a dozen or so bikes, both cassette hubs and
> > freewheel, and have no idea what they're going on about. Moving a hub
> > axle and undishing a wheel are extremely normal and basic
> > concepts--please tell me that I'm not loony for thinking that this kid
> > isn't getting his chain yanked?

>
> >>>

> The shop says that this is "very difficult" and has sold him a bmx hub
> <<<
>
> Trust me, that would only be 'very difficult' for a dumb Limey.
> Fortunately
> there are a few that are smarter than that. :)
>


I thought so. It was so blatant as to have me taken aback a bit.

As the Car Guys on NPR are fond of saying, "Somebody needs to make a
boat payment."
 
not to be a big jerk (i'm one real life though), but why is there
always the assumption that if someone is an engineer, that they know
the inner wrokings of compoenents they've never seen or know anything
about?

i know two engineers who work on their bikes and to this day....they've
cross threaded pedals, packed their freehub pawl/ratchets with truck
diff. grease, rounded out more bolt heads that most mediocre mechaincs
would in their lifetime, and seem to assume a whole hell of a lot,
about things they claim they know nothing about, after having to take
the bikes into the shop.






landotter wrote:
> Penpal over in England is converting an old Peugeot to SS. He's a bike
> noob, but mechanically at engineer level. I told him to take the rear
> wheel to a shop and have them move the axle and get the rear wheel
> "undished" in order to get the chainline right. The shop says that this
> is "very difficult" and has sold him a bmx hub (110mm and I doubt they
> respacered it) and a new rigida rim, plus are charging for a build.
>
> Now I've "singled" a dozen or so bikes, both cassette hubs and
> freewheel, and have no idea what they're going on about. Moving a hub
> axle and undishing a wheel are extremely normal and basic
> concepts--please tell me that I'm not loony for thinking that this kid
> isn't getting his chain yanked?
 
sal bass wrote:
> not to be a big jerk (i'm one real life though), but why is there
> always the assumption that if someone is an engineer, that they know
> the inner wrokings of compoenents they've never seen or know anything
> about?



There's this assumption? Really? Are you inside of my head? Wow, I
didn't know I meant that!

What I mean to infer is that the guy's smart, and quick to learn about
nuts n' bolts.


>
>
>
>
> landotter wrote:
> > Penpal over in England is converting an old Peugeot to SS. He's a bike
> > noob, but mechanically at engineer level. I told him to take the rear
> > wheel to a shop and have them move the axle and get the rear wheel
> > "undished" in order to get the chainline right. The shop says that this
> > is "very difficult" and has sold him a bmx hub (110mm and I doubt they
> > respacered it) and a new rigida rim, plus are charging for a build.
> >
> > Now I've "singled" a dozen or so bikes, both cassette hubs and
> > freewheel, and have no idea what they're going on about. Moving a hub
> > axle and undishing a wheel are extremely normal and basic
> > concepts--please tell me that I'm not loony for thinking that this kid
> > isn't getting his chain yanked?
 
landotter wrote:
> Penpal over in England is converting an old Peugeot to SS. He's a bike
> noob, but mechanically at engineer level. I told him to take the rear
> wheel to a shop and have them move the axle and get the rear wheel
> "undished" in order to get the chainline right. The shop says that this
> is "very difficult" and has sold him a bmx hub (110mm and I doubt they
> respacered it) and a new rigida rim, plus are charging for a build.
>
> Now I've "singled" a dozen or so bikes, both cassette hubs and
> freewheel, and have no idea what they're going on about. Moving a hub
> axle and undishing a wheel are extremely normal and basic
> concepts--please tell me that I'm not loony for thinking that this kid
> isn't getting his chain yanked?


Yer not but you aren't 'undishing' a wheel...you are dishing it,
putting the rim in the center of the axle flats. When you move spacers
from the right to the left side of the axle, it is 'undished'...adding
tension to the left spokes, to center it is 'dishing' it.
 
landotter wrote:
> Penpal over in England is converting an old Peugeot to SS.

<snip>
> Now I've "singled" a dozen or so bikes, both cassette hubs and
> freewheel, and have no idea what they're going on about. Moving a hub
> axle and undishing a wheel are extremely normal and basic
> concepts--please tell me that I'm not loony for thinking that this kid
> isn't getting his chain yanked?


Not defending the shop, but...

The older Peugeots (say early/mid eighteis) were of variable quality.
Nothing to do with PX10s, or other classic Peugeots of 50/60/70s.
These were cheap and cheerful (or perhaps not so cheerful) 10/12 speed
road bikes.Basically gaspipe frames and low end components (low ends
Sachs shifters, Maillard hubs etc), bizarre 24.0mm seat posts etc. You
could get 'em with a mens or a mixte frame, dressed up with a carrier,
bottle dynamo and chrome mudguards, or stripped down "racer" style. A
general "utility" bike.

I've owned several, with both steel and allow rims, and in all cases
the OEM spokes were galvanised cheapos, and the nipples lovingly
machined from cheese which was then coated in tinfoil, ie ****.
The first thing the spokes do is corrode onto the nipples, and because
the nipples are of such low quality, even lots of pentrating oil can't
get em to shift before rounding them.

Correcting an out of true rim would be bad enough, but the thought of
having to redish a whole wheel... ugh.

At shop rates, and if the original wheel is not in good nick anyway, it
might be better to go with a new wheel build rather than fix the old.
That said, I'd have been happier to hear that they'd put in a proper
track hub spaced out to whatever the OLN is.

Regards,

bookieb.
 
sal bass wrote:
> not to be a big jerk (i'm one real life though), but why is there
> always the assumption that if someone is an engineer, that they know
> the inner wrokings of compoenents they've never seen or know anything
> about?
>
> i know two engineers who work on their bikes and to this day....they've
> cross threaded pedals, packed their freehub pawl/ratchets with truck
> diff. grease, rounded out more bolt heads that most mediocre mechaincs
> would in their lifetime, and seem to assume a whole hell of a lot,
> about things they claim they know nothing about, after having to take
> the bikes into the shop.


Yeah, those engineers are all twits. I think what they do at engineering
school is disable their brains. A real education comes from pulling on
wrenches and pounding sand. By the way, I are a engineer so I know.

Anyway, I hope you have a sense of humor because I am just joking
around. Not all engineers are idiots but like any profession, including
doctors and bicycle mechanics, we have our fair share. In fact, this
thread may be about an idiot bicycle mechanic more than it is about an
idiot engineer.
 

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