Dropout/frame alignment



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Mick Collins

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A rear wheel sits off to one side in a frame that I will be selling via eBay. It hasn't bothered me
in use but I'm concerned about my description being honest and accurate, but am also keen not to put
anyone off unnecessarily at the same time!

What can cause the rim of a perfectly dished rear wheel to be nearer to one chain stay than the
other when fitted to a frame with vertical dropouts?

What is the technical term for this (if rim is, say, 2mm off to one side, how should this be
described?), and how much error is acceptable in a mid-price road bike frame (one with minimal/no
clearance for fenders)? It looks worse on this bike than many others, I'm sure, because there's so
little gap anyway between rim and frame, so every mm shows up.

What is the best way of accurately measuring the error? I'm having trouble getting consistent
results with a caliper or ruler so far.

Thanks
 
"Mick Collins" <[email protected]> wrote in message
news:[email protected]...
> A rear wheel sits off to one side in a frame that I will be selling via eBay. It hasn't bothered
> me in use but I'm concerned about my description being honest and accurate, but am also keen not
> to put anyone off unnecessarily at the same time!
>
> What can cause the rim of a perfectly dished rear wheel to be nearer to one chain stay than the
> other when fitted to a frame with vertical dropouts?
>
> What is the technical term for this (if rim is, say, 2mm off to one side, how should this be
> described?), and how much error is acceptable in a mid-price road bike frame (one with minimal/no
> clearance for fenders)? It looks worse on this bike than many others, I'm sure, because there's so
> little gap anyway between rim and frame, so every mm shows up.
>
> What is the best way of accurately measuring the error? I'm having trouble getting consistent
> results with a caliper or ruler so far.

You might consider a consultation with the local frame repair shop. If it is indeed minor, a quick
pass with a 1/4" die grinder will let you advertise "dead straight" on EBay.

--
Andrew Muzi http://www.yellowjersey.org Open every day since 1 April 1971
 
On 19 Feb 2003 08:52:53 -0800, [email protected] (Mick Collins) wrote:

>A rear wheel sits off to one side in a frame that I will be selling via eBay. It hasn't bothered me
>in use but I'm concerned about my description being honest and accurate, but am also keen not to
>put anyone off unnecessarily at the same time!
>
>What can cause the rim of a perfectly dished rear wheel to be nearer to one chain stay than the
>other when fitted to a frame with vertical dropouts?
>
>What is the technical term for this (if rim is, say, 2mm off to one side, how should this be
>described?), and how much error is acceptable in a mid-price road bike frame (one with minimal/no
>clearance for fenders)? It looks worse on this bike than many others, I'm sure, because there's so
>little gap anyway between rim and frame, so every mm shows up.
>
>What is the best way of accurately measuring the error? I'm having trouble getting consistent
>results with a caliper or ruler so far.
>
>Thanks

A good LBS should have a set of drop-out alignment tools from either Park or Campy and a frame
alignment tool... it is usually only a matter of a few minutes work for an experienced mechanic to
straighten out difference as small as you describe...
 
[email protected] (Mick Collins) wrote in message
news:<[email protected]>...
> A rear wheel sits off to one side in a frame that I will be selling via eBay. It hasn't bothered
> me in use but I'm concerned about my description being honest and accurate, but am also keen not
> to put anyone off unnecessarily at the same time!
>
> What can cause the rim of a perfectly dished rear wheel to be nearer to one chain stay than the
> other when fitted to a frame with vertical dropouts?
>
> What is the technical term for this (if rim is, say, 2mm off to one side, how should this be
> described?), and how much error is acceptable in a mid-price road bike frame (one with minimal/no
> clearance for fenders)? It looks worse on this bike than many others, I'm sure, because there's so
> little gap anyway between rim and frame, so every mm shows up.
>
> What is the best way of accurately measuring the error? I'm having trouble getting consistent
> results with a caliper or ruler so far.

Thanks for the replies. However, my questions remain unanswered. I probably won't be taking it to a
shop before selling (inconvenient for me & time is limited).

I mainly want to know how much error you would regard as acceptable in a brand new mid-price road
bike frame, and if I mention it at all in the description, what technical term I should use?.....

"The hoolimawotducallit is within X mm".

What do I say instead of hoolimawotducallit?

Thanks for any help
 
On 20 Feb 2003 16:01:36 -0800, [email protected] (Mick Collins) wrote:

>[email protected] (Mick Collins) wrote in message
>news:<[email protected]>...
>> A rear wheel sits off to one side in a frame that I will be selling via eBay. It hasn't bothered
>> me in use but I'm concerned about my description being honest and accurate, but am also keen not
>> to put anyone off unnecessarily at the same time!
>>
>> What can cause the rim of a perfectly dished rear wheel to be nearer to one chain stay than the
>> other when fitted to a frame with vertical dropouts?
>>
>> What is the technical term for this (if rim is, say, 2mm off to one side, how should this be
>> described?), and how much error is acceptable in a mid-price road bike frame (one with minimal/no
>> clearance for fenders)? It looks worse on this bike than many others, I'm sure, because there's
>> so little gap anyway between rim and frame, so every mm shows up.
>>
>> What is the best way of accurately measuring the error? I'm having trouble getting consistent
>> results with a caliper or ruler so far.
>
>Thanks for the replies. However, my questions remain unanswered. I probably won't be taking it to a
>shop before selling (inconvenient for me & time is limited).
>
>I mainly want to know how much error you would regard as acceptable in a brand new mid-price road
>bike frame, and if I mention it at all in the description, what technical term I should use?.....
>
>"The hoolimawotducallit is within X mm".
>
>What do I say instead of hoolimawotducallit?
>
>Thanks for any help

at a shop no error... second hand? if it is within the 2mm you mention I'd consider that reasonable
(since it is so easy to fix) anything bigger then blame the shipper...

Seriously though I would not specify a measurement since there are so many ways to measure the buyer
may disagree with your number... If you want to be fully honest (for which I applaud you) say simply
" needs very minor rear drop out adjustment/alignment" ...
 
[email protected] (Mick Collins) wrote in message
> Thanks for the replies. However, my questions remain unanswered.

if folks are advocating a pass with a die grinder, you probably couldn't go wrong with a 4 dollar
small half round/round file and ten minutes. if you take it really really slow, you will get
results as good as any shop's grinder. just make sure you think it through before you shave metal
off (the dropout).

even the slightest thing wrong will put off a lot of people on ebay. folks want to hear that it is
'ready to ride'. id fix it, if it were my auction, no matter whether i did it or the shop.

if you are pressed for time, the filing will take but a minute, and you gotta' have one around, no?

cheers
 
On 21 Feb 2003 23:07:28 -0800, [email protected] (ant) wrote:

>[email protected] (Mick Collins) wrote in message
>> Thanks for the replies. However, my questions remain unanswered.
>
>if folks are advocating a pass with a die grinder, you probably couldn't go wrong with a 4 dollar
>small half round/round file and ten minutes. if you take it really really slow, you will get
>results as good as any shop's grinder. just make sure you think it through before you shave metal
>off (the dropout).
>
>even the slightest thing wrong will put off a lot of people on ebay. folks want to hear that it is
>'ready to ride'. id fix it, if it were my auction, no matter whether i did it or the shop.
>
>if you are pressed for time, the filing will take but a minute, and you gotta' have one around, no?
>
>cheers
That being said if I saw evidence of a die grinder or a file having been used on a frame I bought
I would flip...
 
> >[email protected] (Mick Collins) wrote in message
> >> Thanks for the replies. However, my questions remain unanswered.

> On 21 Feb 2003 23:07:28 -0800, [email protected] (ant) wrote:
> >if folks are advocating a pass with a die grinder, you probably couldn't go wrong with a 4 dollar
> >small half round/round file and ten minutes. if you take it really really slow, you will get
> >results as good as any shop's grinder. just make sure you think it through before you shave metal
> >off (the dropout).
> >
> >even the slightest thing wrong will put off a lot of people on ebay. folks want to hear that it
> >is 'ready to ride'. id fix it, if it were my auction, no matter whether i did it or the shop.
> >
> >if you are pressed for time, the filing will take but a minute, and you gotta' have one
> >around, no?

"ajames54" <[email protected]> wrote in message
news:[email protected]...
> That being said if I saw evidence of a die grinder or a file having been used on a frame I
> bought I would flip...

But the whole idea is that you cannot tell. And what we do is not different from what the factory QC
station does - on the days they work!

--
Andrew Muzi http://www.yellowjersey.org Open every day since 1 April 1971
 
ajames54 <[email protected]> wrote in message
news:<[email protected]>...

> That being said if I saw evidence of a die grinder or a file having been used on a frame I
> bought I would flip...

I agree, pure butchery!!

For a frame with vertical dropouts, grinding/filing the dropouts will not help. The problem is one
of two things: 1) the chain stays are unequal length or 2) the chain stays are not aligned to the
centerline of the frame. If the problem is 1), you are screwed since there is no good way to fix
this without breaking out the brazing torch. If the problem is 2), the rear stays can be alighed by
cold-setting them straight.

One way to check alignment:

1) Take a long string attached to the inside surface of one rear dropout
2) Wrap string around the head tube and then back to the other dropout
3) Measure the distance from the string to the seat tube on both the right and left sides of the
frame. The distance should be the same.
4) Bend the stays until the distance is the same.

A fair bit of work but better than trying to sell junk on ebay.

Good luck.

Ed
 
On Mon, 24 Feb 2003 13:30:32 GMT ajames54 <[email protected]> wrote:

> That being said if I saw evidence of a die grinder or a file having been used on a frame I bought
> I would flip...

Keep in mind that any really good frame had a lot of die grinder or file work done on it at
the factory.

-
-----------------------------------------------
Jim Adney [email protected] Madison, WI 53711 USA
-----------------------------------------------
 
[email protected] (Ed Ness) wrote in message
news:<[email protected]>...
> ajames54 <[email protected]> wrote in message
> news:<[email protected]>...
>
> > That being said if I saw evidence of a die grinder or a file having been used on a frame I
> > bought I would flip...
>
> I agree, pure butchery!!
>
> For a frame with vertical dropouts, grinding/filing the dropouts will not help.

I'm confused and worried now because it DID help! Thanks Ant, I think!
:) Filing the bottom of one vertical dropout made the wheel move over
to one side. But I suppose it means the wheel might be tilting over a tiny bit. Does this matter?

The error was small so a small amount of filing fixed it. I did a neat job, but of course the finish
on droputs don't match each other. Due to the frame's finish (which I won't reveal here), it doesn't
show up terribly much but the evidence is there.

> One way to check alignment:
>
> 1) Take a long string attached to the inside surface of one rear dropout
> 2) Wrap string around the head tube and then back to the other dropout
> 3) Measure the distance from the string to the seat tube on both the right and left sides of the
> frame. The distance should be the same.
> 4) Bend the stays until the distance is the same.

1) _I'm_ never going to get an accurate and precise measurement like this.
2) I aint doin no bendin!

> A fair bit of work but better than trying to sell junk on ebay.

I don't think it was or is junk. Since any remaining fault would be too small to ever notice on the
road, it's just a question of cosmetics, trust, honesty, and last but not least, money!

Would it be nuts to lightly file and sand the other dropout just enough so it looks the same (but
not enough to alter the alignment)?

> Good luck.

Thank you.

I would still appreciate any more advice from others and second opinions on Ed's post.
 
On 25 Feb 2003 18:14:31 -0800, [email protected] (Mick Collins) wrote:

>[email protected] (Ed Ness) wrote in message
>news:<[email protected]>...
>> ajames54 <[email protected]> wrote in message
>> news:<[email protected]>...
>>
>> > That being said if I saw evidence of a die grinder or a file having been used on a frame I
>> > bought I would flip...
>>
>> I agree, pure butchery!!
>>
>> For a frame with vertical dropouts, grinding/filing the dropouts will not help.
>
>I'm confused and worried now because it DID help! Thanks Ant, I think!
>:) Filing the bottom of one vertical dropout <snip>

The bottom of a Vertical Dropout? Maybe a Horizontal Dropout? or the Top of the Vertical Dropout?

If it is a matter of removing built up paint then that is one thing... but to remove material from
the dropout without first checking to see if it is a simple alignment issue .. well to be honest I
don't even have words to describe how low an opinion I have of that... butchery comes close.
 
A Muzi wrote: << There are plenty of times when a die grinder is the right tool.>>

Could you give some examples please (just to possibly set my mind at ease)? Thanks.
 
[email protected] (Mick Collins) wrote in message

> Filing the [top] of one vertical dropout made the wheel move over to one side.

I now realise this was a dumb move, but can someone please tell me if it will result in any
practical problems.
 
Sure. Factory bike new out of the box with an end brazed in crooked or too close/far from the BB
compared to the other side. Everything else is in order. The wheel won't sit straight in the
bicycle, to one side, say 4 or
5mm. A very deft touch with a 1/4" rotary file moves the wheel back to center. Note that one mm at
the axle moves the wheel a very long way at the rim, something like 5mm!

As discussed earlier, one needs to ensure that that is indeed the problem. The word "butchery" was
used, appropriately, to describe whacking material from a perfectly good frame with an uncenetered
wheel or a simple rear lateral alignment problem.

I compared that to riders who anguish over "brake centering" when in fact their wheel isn't in the
bike straight. That is an everyday occurrence. If metal cutting tools were available to that sort
of person, bikes would be butchered through impetuousness and not measuring things before jumping
in to cut.

With modern carbon forks, when a wheel sits off center a small amount we cannot do an alignment
because carbon will not move short of failure. A judiciuous trim of the end is a reasonable
alternate to tossing out the fork. Those are the only two avenues available.
--
Andrew Muzi http://www.yellowjersey.org Open every day since 1 April 1971 "Mick Collins"
<[email protected]> wrote in message news:[email protected]...
> A Muzi wrote: << There are plenty of times when a die grinder is the right tool.>>
>
> Could you give some examples please (just to possibly set my mind at
ease)? Thanks.
 
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