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-   -   1980's Frame Misalignment (https://www.bikeforums.net/showthread.php?t=1256784)

branko_76 08-12-22 08:33 PM

1980's Frame Misalignment
 
Most of the bikes I've owned and worked on were 1970's era Raleigh's and all have had misaligned frames. This is the second bike I've worked on from the 1980's and both have misaligned frames. First was a ROSS Signature, this one is a SCHWINN Traveler.

How common is this?

The first photo is of the non-drive side, second is drive side, the gap is 7mm. The dropouts are parallel and are perfectly spaced for a 126mm hub.


https://cimg2.ibsrv.net/gimg/bikefor...40cefcd48b.jpg


https://cimg3.ibsrv.net/gimg/bikefor...281ba827cd.jpg

bertinjim 08-12-22 09:01 PM

branko 76-

Misalignment of older steel bikes is pretty common in my experience. Wear and tear, getting crashed or dropped, all sorts of things happen over 40 years. I routinely have my bike purchases checked by a nearby frame builder and then aligned. It makes a great difference in the ride and tracking even when I previously considered the bike to be fine.

branko_76 08-12-22 09:13 PM


Originally Posted by bertinjim (Post 22608568)
branko 76-

Misalignment of older steel bikes is pretty common in my experience. Wear and tear, getting crashed or dropped, all sorts of things happen over 40 years. I routinely have my bike purchases checked by a nearby frame builder and then aligned. It makes a great difference in the ride and tracking even when I previously considered the bike to be fine.

In complete agreement

3alarmer 08-12-22 09:17 PM

.
...of the stuff I have redone for my own use, probably 70% of them need some sort of either minor or major realignment. As stated above, it's pretty common.
I routinely check the dropout spacing and alignment, frame alignment, fork alignment, and derailleur hanger alignment as part of the process on every bike I work on.

If a bike gets used, **** happens. And some of them were not well aligned when sold new, anyway.

easyupbug 08-13-22 10:06 AM

It is worth the trouble. My worst was 7 years ago an utterly unridable 80's custom from a local builder. Hung upside down by strings looped through the rims the fork would cant off 30º. A lugged Reynolds 753 which you can find Reynolds engineers documents saying 753 can not be cold set. I tried to cold set the fork first and as soon as i mount and moved it would snap back to the original position. Fortunately an old time framebuilder in town with Marchetti frame table and Lange fork table got it perfect. I enjoy it to this day.
https://cimg0.ibsrv.net/gimg/bikefor...21ad1b4a7.jpeg

zandoval 08-13-22 10:19 AM


Originally Posted by bertinjim (Post 22608568)
branko 76-

Misalignment of older steel bikes is pretty common in my experience. Wear and tear, getting crashed or dropped, all sorts of things happen over 40 years. I routinely have my bike purchases checked by a nearby frame builder and then aligned. It makes a great difference in the ride and tracking even when I previously considered the bike to be fine.

For me just getting proper derailleur alignment has been a great thing. And I don't even have proper tools to do it. I just use two large "C" clamps.

As to the OP: Yes, pretty common. A further question would be what methods can we use as a DIY alignment check.

Our guys at Sheldon have a few things posted

https://cimg3.ibsrv.net/gimg/bikefor...6dad352b3e.jpg
https://sheldonbrown.com/frame-spacing.html

randyjawa 08-13-22 03:12 PM

Yup, tweaked frame alignment is not at all uncommon. I always check frame and fork alignment and correct as required. And, in many cases, correction is required. I use the string method to check stays alignment but I no longer have a fork gauge. Stupid me sold mine a long time ago:-(

bulgie 08-13-22 04:15 PM

Alarming that ShelBroCo would show a picture of doing it wrong. (I am admittedly too picky by half, but why not do it right? It's not any harder.)

The string should come off the dropout at a point that matters, namely where the wheel will sit, the inner face of the "land" for the axle. This shows the string coming off a part of the dropout that's not involved with holding the axle, and it's different between the right and left (that knot can throw off the string's centerline).

Even if you do it right, you might want to measure and compensate for the curve in the seat tube from brazing on the front derailer attachment. All tubes have some runout of course, nothing is perfectly straight, but the F. der. BO puts a pretty decent curve in the tube, more than any runout I have measured in an unbrazed tube.

So the string method is not the ultimate alignment, but it's decent as a shade-tree mechanic technique for those without more rigorous methods, or even for a pro framebuilder in too much of a hurry for a complete alignment, say for a frame that isn't valuable enough to warrant the complete tear-down and rebuild. Just run that string in the right place, and try to see how bent your seattube is!

Note this string method (done right) is equivalent to the Park ***-1 tool shown in the OP; they measure the same thing. So the ***-1 (or -2) is also, in my opinion, not a "be-all and end-all" pro alignment tool, but it is very fast and easy to use. I have one and use it, but I keep its limitations in mind.

EDIT: the asterisks were put there by the censor. They replace the name of the Park Frame Alignment Gauge.
I, for one, welcome our new robot overlords!

Mark B

bulgie 08-13-22 04:43 PM


Originally Posted by easyupbug (Post 22608885)
<snip> you can find Reynolds engineers documents saying 753 can not be cold set. I tried to cold set the fork first and as soon as i mount and moved it would snap back to the original position. Fortunately an old time framebuilder in town with Marchetti frame table and Lange fork table got it perfect. I enjoy it to this day.

Yeah it's "common knowledge" that 753 can't be cold-set, but what they really should have said is it's difficult to cold set. If it springs back without taking a set, it just means you didn't push hard enough. Any steel, no matter how strong, can be bent, unless it's too brittle and snaps. But the problem with 753 isn't brittleness, it's just very thinwall (in the frame tubes, not the fork), making it likely to buckle or kink, a.k.a. beercan failure mode.

That's not a problem with the forks though, which are no thinner than 531. They're just 531 blades that got heat-treated to make them stronger, a very dubious advantage since 531 forks are strong enough. (I'm mad at Reynolds for "chickening out" and not making the blades lighter, a missed opportunity.)

The 753 steerer is also the same gauge as 531 for most of its length, but where the 531 steerer gets a butt at the bottom, the 753 doesn't, so the lower part of the steerer is lighter than 531. This a 753 fork is just a little bit lighter than a 531 fork, but it's really very little, like an ounce? Sorrry, I once knew the weight difference but I forget now, someone here will know.

Even if the blades were infinitely strong, you can still bend the crown, so yeah those forks definitely can be cold-set. You just need a longer lever, and a stout vise! Or a 100+ lb alignment fixture like the one I made recently from vintage cast iron industrial parts,

https://cimg9.ibsrv.net/gimg/bikefor...8fbe3eb6f5.jpg
That's a work-in-progress shot. It's now finished and bolted down to a very heavy steel table that's bolted into the concrete floor. Main difference from this pic is the handwheel is spaced upward an inch so you don't pinch your fingers against the crown. Unfortunately it only does 1" forks (I'm a committed C&V retrogrouch).

Mark B

repechage 08-13-22 04:49 PM

Braze on front derailleur mounts are definitely a way to bow a seat tube.

easyupbug 08-13-22 09:40 PM


Originally Posted by bulgie (Post 22609242)
...(I'm a committed C&V retrogrouch).

Mark B

and an inspiration to all us tinkerer.

JohnDThompson 08-14-22 08:23 AM


Originally Posted by bulgie (Post 22609242)
Yeah it's "common knowledge" that 753 can't be cold-set, but what they really should have said is it's difficult to cold set. If it springs back without taking a set, it just means you didn't push hard enough. Any steel, no matter how strong, can be bent, unless it's too brittle and snaps. But the problem with 753 isn't brittleness, it's just very thinwall (in the frame tubes, not the fork), making it likely to buckle or kink, a.k.a. beercan failure mode.

When I was with Trek, we decided to test cold-setting a 753 frame on a crashed team frame that was headed for the scrap barrel anyway. Put it on the alignment table and had at it with the Big Levers of Alignment, and just as you say, it kept springing back, and we kept increasing the force. Finally, it gave, by crumpling at the shift lever bosses.

And that's why I don't recommend cold-setting 753 frames.

Doug Fattic 08-14-22 10:23 AM

I'll start by answering the OP's question about how often are classic era bike frames out of alignment. As a builder/painter since the mid 70's, I've done hundreds (thousands probably) of alignments. The answer is most frames are somewhat out of alignment and some seriously out. I've visited many framebuilding places (especially in the UK) in the 70's and most were pretty casual about it with rudimentary tools. Furthermore, the $100/150 retail cost of a painted frame in Europe required those builders to make them quickly. The exception I've found were 80's Japanese frames that always seemed to be spot on. American builders raised the price and standard although not everyone does it perfectly. Where I learned to build at Ellis Briggs in Yorkshire, they had a very nice cast iron fixture/alignment table combination. I took back with me from Manchester much of Johnny Berry's Equipment including his 3' X 4' cast iron table. I've gotten others since but that one is still my main table for alignment. I was very fortunate to get it (and the knowledge of how to use it).

The problem with DIY alignment is figuring out what is the problem. I'm not a fan of Sheldon's string method. So you measure the distance of the string to the seat tube on both sids and there is a discrepancy. What's off? One might think that the rear dropouts are left or right of the center of the frame but how do you know? Maybe the down tube is leaning over to one side or maybe it's the seat tube leaning but not the head tube. Or the other way around. Or both. Or the front triangle is really 90 degrees from the threads of the bottom bracket shell and the dropouts are really off center. So the string method is only telling you something isn't right but it can't tell you where to fix what is wrong. There is a way to DIY if one wants to make a straight edge with an adjustable screw but that is beyond the scope of my post.

Just for your amusement, I'll show a couple of pictures of frames and accessories on my Johnny Berry alignment table. The 1st picture shows a carved lug frame I was making for my nephew. The other picture shows 3 kinds of straight edges with adjustable screws.
https://cimg1.ibsrv.net/gimg/bikefor...63e20816b.jpeg
some of the accessories to check frame alignment on a cast iron table

https://cimg5.ibsrv.net/gimg/bikefor...af4c03587.jpeg
a gaggle of straight edges that can be used in checking alignment

bulgie 08-14-22 04:18 PM


Originally Posted by JohnDThompson (Post 22609708)
When I was with Trek, we decided to test cold-setting a 753 frame on a crashed team frame that was headed for the scrap barrel anyway. Put it on the alignment table and had at it with the Big Levers of Alignment, and just as you say, it kept springing back, and we kept increasing the force. Finally, it gave, by crumpling at the shift lever bosses.

And that's why I don't recommend cold-setting 753 frames.

Right, I think you're agreeing with what I wrote. But do you agree that 753 forks should be alignable? (Is that a word?) Can't say as I recall ever having tried it, but I have aligned Prestige forks (maybe a thousand times, but weaker than 753) and a fair number of 853, which ISTR is even stronger than 753.

Mark B

reroll 08-14-22 05:14 PM


Originally Posted by zandoval (Post 22608892)
For me just getting proper derailleur alignment has been a great thing. And I don't even have proper tools to do it. I just use two large "C" clamps.

As to the OP: Yes, pretty common. A further question would be what methods can we use as a DIY alignment check.

Our guys at Sheldon have a few things posted

https://cimg3.ibsrv.net/gimg/bikefor...6dad352b3e.jpg
https://sheldonbrown.com/frame-spacing.html

Just the info I needed, the Sheldon dropout alignment check photo, at just the right time, thank you!

Bought a vintage frame set, being shipped to me now, and I wanted to do an alignment check on it.

reroll 08-14-22 05:25 PM


Originally Posted by bulgie (Post 22609207)
Alarming that ShelBroCo would show a picture of doing it wrong. (I am admittedly too picky by half, but why not do it right? It's not any harder.)

The string should come off the dropout at a point that matters, namely where the wheel will sit, the inner face of the "land" for the axle. This shows the string coming off a part of the dropout that's not involved with holding the axle, and it's different between the right and left (that knot can throw off the string's centerline).

Even if you do it right, you might want to measure and compensate for the curve in the seat tube from brazing on the front derailer attachment. All tubes have some runout of course, nothing is perfectly straight, but the F. der. BO puts a pretty decent curve in the tube, more than any runout I have measured in an unbrazed tube.

So the string method is not the ultimate alignment, but it's decent as a shade-tree mechanic technique for those without more rigorous methods, or even for a pro framebuilder in too much of a hurry for a complete alignment, say for a frame that isn't valuable enough to warrant the complete tear-down and rebuild. Just run that string in the right place, and try to see how bent your seattube is!

Note this string method (done right) is equivalent to the Park ***-1 tool shown in the OP; they measure the same thing. So the ***-1 (or -2) is also, in my opinion, not a "be-all and end-all" pro alignment tool, but it is very fast and easy to use. I have one and use it, but I keep its limitations in mind.

EDIT: the asterisks were put there by the censor. They replace the name of the Park Frame Alignment Gauge.
I, for one, welcome our new robot overlords!

Mark B

Your information has been noted, thank you!

easyupbug 08-14-22 05:36 PM


Originally Posted by Doug Fattic (Post 22609798)
I'm not a fan of Sheldon's string method...

The above 753 Andy saved hung afterward by strings run through the rims hung straight as an arrow and it fails Sheldon's string test badly but I can ride it around the block w/o touching the handlebars, it is a delight. Andy also painted it for me, he is a gilt to C&V in Southern Arizona and I recall him saying basically what you did above.

JohnDThompson 08-14-22 05:42 PM

4 Attachment(s)

Originally Posted by bulgie (Post 22610102)
Right, I think you're agreeing with what I wrote. But do you agree that 753 forks should be alignable? (Is that a word?) Can't say as I recall ever having tried it, but I have aligned Prestige forks (maybe a thousand times, but weaker than 753) and a fair number of 853, which ISTR is even stronger than 753.

I'm pretty sure we were able to align 753 forks. The early production used Ishiwata SCM crowns, which we milled out to profile the crown. Those seemed to bend at the crown when aligned; we dubbed them "frame saver forks." Later production used a Tange crown, but I don't recall any issues with those.

reroll 08-14-22 05:42 PM


Originally Posted by Doug Fattic (Post 22609798)
The problem with DIY alignment is figuring out what is the problem. I'm not a fan of Sheldon's string method. So you measure the distance of the string to the seat tube on both sids and there is a discrepancy. What's off? One might think that the rear dropouts are left or right of the center of the frame but how do you know? Maybe the down tube is leaning over to one side or maybe it's the seat tube leaning but not the head tube. Or the other way around. Or both. Or the front triangle is really 90 degrees from the threads of the bottom bracket shell and the dropouts are really off center. So the string method is only telling you something isn't right but it can't tell you where to fix what is wrong. There is a way to DIY if one wants to make a straight edge with an adjustable screw but that is beyond the scope of my post.

Yes, that big, flat, smooth iron table sure does look useful.


https://cimg1.ibsrv.net/gimg/bikefor...63e20816b.jpeg
some of the accessories to check frame alignment on a cast iron table

https://cimg5.ibsrv.net/gimg/bikefor...af4c03587.jpeg
a gaggle of straight edges that can be used in checking alignment

Road Fan 08-14-22 09:04 PM


Originally Posted by bulgie (Post 22609242)
Yeah it's "common knowledge" that 753 can't be cold-set, but what they really should have said is it's difficult to cold set. If it springs back without taking a set, it just means you didn't push hard enough. Any steel, no matter how strong, can be bent, unless it's too brittle and snaps. But the problem with 753 isn't brittleness, it's just very thinwall (in the frame tubes, not the fork), making it likely to buckle or kink, a.k.a. beercan failure mode.

That's not a problem with the forks though, which are no thinner than 531. They're just 531 blades that got heat-treated to make them stronger, a very dubious advantage since 531 forks are strong enough. (I'm mad at Reynolds for "chickening out" and not making the blades lighter, a missed opportunity.)

The 753 steerer is also the same gauge as 531 for most of its lenght, but where the 531 steerer gets a butt at the bottom, the 753 doesn't, so the lower part of the steerer is lighter than 531. This a 753 fork is just a little bit lighter than a 531 fork, but it's really very little, like an ounce? Sorrry, I once knew the weight difference but I forget now, someone here will know.

Even if the blades were infinitely strong, you can still bend the crown, so yeah those forks definitely can be cold-set. You just need a longer lever, and a stout vise! Or a 100+ lb alignment fixture like the one I made recently from vintage cast iron industrial parts,

https://cimg9.ibsrv.net/gimg/bikefor...8fbe3eb6f5.jpg
That's a work-in-progress shot. It's now finished and bolted down to a very heavy steel table that's bolted into the concrete floor. Main difference from this pic is the handwheel is spaced upward an inch so you don't pinch your fingers against the crown. Unfortunately it only does 1" forks (I'm a committed C&V retrogrouch).

Mark B

Mark, that looks like a great tool coming into being! By coinidence I've just concluded the Terry ridden by Mrs Road Fan has a back-bend t teh fork crown. I can see it in a sice view of the bike, but I haven't undone the fork to et a real look at it. After the Auburn show I'll have to take it to Mr. Fattic and see what he says.


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