Fredo76

I helped my powder-coater/framebuilder Charlie O'Leary reset mine, and am glad I did. Probably could have done it myself, but was glad to have the extra experience and tools, similar to Doug's post above. We got it to 128mm and aligned (that second part is important!) after a couple hours of wrestling with it, and called it good. It came out of the oven at 126mm. My old training and racing wheels went to 6-speed, and I got a new pair of 7-speed training wheels. I have a pair of carbon wheels that I haven't tried yet, 130mm and 8 speed.

After a new powder-coating job, I got pretty fond of the classic look again.

Historical significance to me means something like Merckx winning a stage on it, not just a particular brand or model, unless really rare. It's your bike - do what you want with it, I say.

I hope sew-ups make a comeback, with some larger sizes available. To me, removable presta value cores, Stan's tire sealant, and double-sided rim tape instead of glue makes them viable again - I've resurrected four. My racing pair are lighter than my carbon wheels.

Doug Fattic 

I'm assuming you are referring to the string around the head tube and attached to each dropout and then measure the distance from the string to the seat tube, yes? This is not a good system and does not provide a professional result. The problem with this method is that it assumes the front part of the triangle is actually aligned. In other words the seat and head tubes are exactly 90 degrees to the threads in the BB and the head tube is exactly in plane with the seat tube. This is most often not the case with classic era steel frames. If anything is leaning then the measurement to the seat tube will not be true. If one is using a 2X4 and leveraging it against any part of the front triangle, it is likely to throw the front triangle out of whack. It will move as easily as the rear triangle.

Before I mess with widening the dropouts, I make sure the front triangle is aligned and the easiest best way is with my alignment table. I can brace the front triangle tubes to keep them from moving when bending the back end. There are ways to do that without a big table but that is beyond the scope of this discussion.

It can take a lot of force with H tools to bend the dropouts parallel. A lot. The bolt and washer method can be diagnostic but then you have to bend them. And then the dropout hanger has to be checked and trued. There is probably some amateur way of doing it but I have the right tools to do the job so I'm not trying to figure out some amateur way to do the job.

SurferRosa

Damn, I've been doing it wrong all these years! I wonder how many watts I'm losing?

The thing I absolutely adore about Sheldon Brown is that he doesn't scare people. He empowers them ... to do all their own work with very basic tools and easy to follow instruction concerning a very simple machine.

reissue59

I just slip in a 130 wheel, slightly spreading the rear stays, usually works . Adjust the hanger and give it a go. If it goes to sh@t, i just bring it to Marinoni, 30$ for spreading, dropout adjust and hanger. Kinda lucky, 40 min drive

davester

"Works" is a subjective term. If you mean that the wheel will turn but then the stress on the axle from the misaligned dropouts eventually either breaks the axle, prematurely wears the bearing races and/or cracks the dropout, then you are correct.

Chombi1 

I remember spreading the rear triangle on my 82 Peugeot PH10S back in the early 80's. The only bike I ever cold set
I built up a new wheelset (w/ 126mm OLD rear wheel)for the bike and I was surprised when the rear wheel did not fit between the rear dropouts.
I suspect it's because the PH10 had 120 or 122mm OLD spacing.
decbikedecido the spreading of the rear stays as it looked pretty close to where I had to have it so the new rearshhel would fit.
Got it wide enough with no problem, except the dropouts faces were not perfectly parallel, so the new wheel does not drop in or pull out as easily as the original wheel that was on the bike. I was new to cycling so I thought this was no big deal and I can live with the slightly tight fit.
The thing that surprised me though was how much force it to to bend the stays the 6mm additional width. IIRC, i had to have my brother help me do it with me onone side of the rear triangle and I on the other.
That Carbolite 103 frame sprung back pretty hard and it took quite a few hard pull to get it to budge.
I suspect other frames with higher quality tubing would be even harder to cold set.

repechage

Nah, just may not be able to ride "no hands" effectively.
Might shimmy on a descent.
Minor details. Why settle for mediocrity when perfection is within reach?
A bicycle is quite tolerant of being rideable even when really skewed.
Like the pick-up trucks you find yourself driving behind where the front wheels are displaced to one side by a noticeable amount to the rears, it still "works"

SurferRosa

Seriously! Why don't all c&v members here get all their frames professionally aligned? Mediocre!

t2p

the rear triangle on my vintage Schwinn Peloton was spread using the same process described above by Doug Fattic

in fact - all of my better bikes / frames went through a similar process - BB and head tube faced, frame and fork checked for alignment, measurements taken/documented (including trail, etc)

I was fortunate have a friend that was a custom frame builder

had one bike/frame that didn't 'survive' the process - early 90's Cannondale R800 2.8 frame and fork both out of alignment ... they were scrapped

bamboobike4

I don’t disagree with the points of view expressed herein.
I’m not a professional.
I don’t play one on TV.

I just don’t follow any real guidelines.
Dozens of builds, 126 to 130 setups.
Thumb pressure seems to work.

Never an issue, but if there is one, I’ll drop $200 on a used bike and build another.

Probably just guaranteed that jinx.

sdn40

Only if bikes somehow become as important as the Declaration of Independence

Lenton58 

I'll add a couple of stuffs, although it looks like it maybe superfluous:

• The sports bike LBS I went to for years refused to do it. And they were adamant. They would do anything else and understood bicycles having been competition cyclists

• A frame builder who was licensed to repair crashed Keirin racing bicycles did a complete servicing on all the frames I own. He once spread some 120 stays to 126. After watching him, I would certainly never do it myself. For starters, I don't have a suitable table — let alone the tools. To watch him was a treat. Every move he made was like a choreographed dance, all in sequence and never a pause in motion. (Sadly, he retired from frame making due to ill health ... so I hear, and AFAIK, there's no more professional frame-making in Sendai or even in all off Northern Japan.) [[b]Edit: There is a builder here in Sendai, and I think he is certified JIS. Just found this out — Nov, '22. And I should not have made such a generalized statement, because there could be others in Northern Japan that my inquiries have not revealed.]

• NEVER move an aluminum frame. Well, that's just MY advice. I have a Vitus 979, and I'm moving nothing on it — ever. If it gets bent, it gets junked. Someone may disagree, but I'm not going to be riding their aluminum bicycles.

diphthong

do as you like. how many people do you ride with that are going to break out the calipers? rhetorical question potentially...

JackJohn

I believe knowing the proper professional method and the diy method are complementary rather than conflicting information to have at hand. The pro tells how it “should” be done to avoid minor or major problems, while alternative simpler methods are a useful guide to do the job yourself. Knowing both allows to understand where issues may come from and let people decide which way to go and judge the imperfections they’re willing to accept or not. This is the real “empowering” for me and I’m glad all this knowledge is shared in this forum.

Classtime 

When I only had one bike, I had a pro do it to my less rare than a Cinelli SC and regret it. I did it myself with string, nuts, and bolts to a common Japanese mid-upper level racer and would do it again.

edit: A Cinelli SC is not your bike. You are only the caretaker and it is Taboo.

Jeff Neese

It's only an original "as built" Cinelli SC (handbuilt in Italy by skilled framebuilders, as I understand) until you start modifying it. I think Luigi would turn over in his grave at the thought of someone bending up his frame in their garage, using 2x4s and some string. And I know I would never buy a high-end steel bike if the frame has been modified. The only exception would be if there is clear documentation that it was done by a skilled framebuilder, and done right as has been described above. Even then, it still devalues the frame, at least as far as collectibility or resale value. As others have said, you have freewheel options that don't require you to bend your frame. Leave it alone.

repechage

you are tolerant of out of tolerance.
as I wrote, a bicycle will be rideable still when way out of whack.
if you have no problems, terrific.

SurferRosa

smd4

All this consternation and gnashing of teeth for four millimeters? Please. You are now on the list of people forbidden from buying my bike.

SJX426 

WRT 2x4. I entertained buying a Bianchi in 2009 after impinging on a fender of a car with my bike and the roof with my body.

The reason I didn't was the forks had dents from the 2 part of the 2x4. Must have had a stuck stem. The flats were on both legs but one in front and the other in back. Wasn't noticeable until close inspection for tangs on the inside of the legs.

Busted brake or chain bridges is another gotcha. They need to be clamped.

My preference would be to have a frame builder do it for anything I really value that is not common to find, like a '70s Cinelli SC. A Trek 610, maybe.

I confess to bending a Trek 760 front fork back to specifications, much to Mr Fattic's consternation. I used a 10' 2x4 and then a fixture for alignment and trail check. It worked out. I would not do it again.

Doug Fattic 

Just to be clear, i'm not opposed to using a 2X4 when I am not strong enough to budge something. I've used them on stubborn frames attached to my alignment table. I don't think they should be used the Sheldon Brown way however. Sheldon puts the end against the seat tube. The force used to bend the stays can also likely bend the seat tube to the side (I place the end against my table instead). The reason this is a problem is because a leaning seat tube can be a source of knee problems. When the bike is being ridden, the seat tube will automatically be straight up vertical. Now the BB is tilted with the result that your pedal platforms are tilted. Crooked pedals can create knee issues. Way back in the 80's when the FitKit came out with their cleat alignment system, they also had to come out with a frame alignment system. Otherwise without an aligned frame, they could not solve cleat and by extension knee problems. That was one of the reasons for a customer to get a cleat adjustment in the 1st place.

Sheldon Brown’s writings are a great asset to available bicycling knowledge. I refer to him when I need to know something not in my area of expertise. But everything he ever wrote is not Gospel truth. He has written he spent 2 weeks in Evanston, IL making a frame under the guidance of a Robert Myers in 1974. According to Sheldon, Robert leaned in a 2 week Eisentraut class. I wish he had spent a little more time making frames before writing how to spread the rear dropouts. His method ignores how an accurate rear triangle alignment is dependent on an accurate front triangle alignment. To divorce the 2 means the front and rear wheels might won’t be inline. Common sense should tell anyone that spreading the back with a 2X4 placed against the seat tube might move the seat tube too. And that throws off the string measurement to the seat tube. Frame builders don’t measure at the seat tube half way point anyway, they measure at the dropouts for greater accuracy.

rccardr 

I think we need to consider the relationship between money, time, and convenience. It’s great to say ‘take it to a frame builder’ but a frame worth $200 and a round trip shipping bill of $150 make that impractical for many.
Just for the record, every frame I’ve had repainted went to a painter who was also a frame builder, so any mods to the frame (eg cold setting) were done right and aligned properly.
However, on multiple occasions I’ve simply inserted a 130 hub into a set of 126 drops. Some of those bikes (including aluminum framed Cannondales) have literally tens of thousands of miles on them with nary an assplosion in sight.
Oh, and since I just bought a rear hanger alignment tool a year or so ago, until then none of them had the drops or hanger fooled with. Guess what? They all index shifted just fine.
So,there’s that.

Spaghetti Legs 

Doc’s post above reminded me of the one time I cold set a frame. Doc very kindly gave me a Ross frame to build into a city bike for my wife. It was, I believe 120 spaced. I carefully read Sheldon’s instructions and then laid the frame on the basement floor and levered it with a shovel handle with a foot on the opposite chainstay. Flipped over and repeated on the other side. Wife has been happily riding it for a couple of years now.

I would not, however, use that method on a Supercorsa.

Doug Fattic 

Remember that the OP was asking about altering a valuable classic Cinelli so my suggestions were directed to his question and not how to spread a $100 beater from Goodwill. In my answer I also wanted people to know there are better ways of aligning a frame than Sheldon's method because rear alignment is connected to front alignment. If one understands how a pro does it, that information can be used as a reference on how they can do it themselves. .

As explained previously the most important alignment on a frame is the seat tube to BB threads to avoid knee injuries. This can be checked with some kind of straight edge. In Ukraine where we build frames/bicycles for Ukrainian pastors, we used a long yellow aluminum level (with bubbles) with ground sides we bought inexpensively at a big box store (now burned to the ground). On one end we tapped a M6 threaded hole for a long M6 bolt we modified so it had a rounded pointed tip. You can find it at the top of our tool board in the picture of the inside of our shop in Bucha. I'm wondering if that level is still there after the Russians broke in and stole what they wanted. Fortunately they only took general use tools and not the bicycle specific ones (as I understand it). And strangely my sport touring Trek I realigned, repainted and reequipped with Campy 8 speed for my use when in Ukraine was just left for weeks in a storage shed with the doors busted wide open.

This straight edge can be placed against the side of the BB shell for checking purposes. If the BB shell is not faced properly, a BB cup can be threaded in and the straight edge placed against the cup. Down at the bottom of the seat tube the adjuster screw is turned until it just touches the seat tube. Now the level is raised so the screw is placed at the top of the seat tube to see if the distance from the tip of the screw to the seat tube is the same. If not, the frame can be clamped in a vise and yanked until it does. Once that is done the same thing can be done on the down tube. Head tube twist is more complicated and less important so I'll skip that for now.

After the the seat and head tube are bent perpendicular the the BB threads, the straight edge placed against the front triangle can be used to check the alignment of the rear dropouts. The straight edge is placed against the head and seat tubes so the adjuster screw when turned just touches the inside face of a dropout on one side. The SE is now placed on the other side to see if the other dropout is equidistant to the frame's centerline. Push and pull and measure until they are 130.5 apart. After that your cut bolts can be used to measure parallelism and a crescent wrench used to adjust them until they are parallel.


The framebuilding end of our shop in Bucha Ukraine including an alignment table.

bark_eater 

Doug Fattic Do you think a Wixey angle finder is useful for checking for things like head tube twist? Or at least indicating what direction a twist might influence "Kentucky windage"?