gugie 

Good points!

Salamandrine 

In the days of when everyone was converting 120 to 126, and freewheels were all there was, it was very important to properly reset the frame and realign the dropouts. If you just forced it in, broken axles could be expected.

Nowadays with freehubs, if you wanted to be sloppy you could just let it go. Frame alignment may be a bit off since the right and left chainstays don't always bend equally.

That said, I would suggest you do align it, because I am an ex mechanic and it is always better do do things properly. Either DIY or take it to a good bike shop. Resetting a frame isn't rocket science. It is very important that the dropouts and derailleur hanger be aligned afterwards. Don't overlook it. Sheldon's DIY methods are solid. The all thread method is totally stupid. A 2x4 or 2x6 isn't functionally a lot different from a Park frame tool, and string is actually just as accurate a way to check alignment as the special tool.

TimmyT 

A string is *not* as accurate as a special tool to measure the dropouts. The reason for this is that the deflection of the string is less along the seat tube and is hard to measure accurately, particularly if the string slips along the head tube.

That said, it is possible to make a much more accurate tool, with a few bolts, some aluminum stock, a hacksaw and a drill. I made one for about $10. Given the amount I use the tool, it doesn't make sense for me to have something more complicated.

CycleryNorth81

I brought my 1980s frame to a frame builder to spread from 120mm to 130mm. He recommended 128mm. That way you can use 126 or 130 axles, freewheel or freehub.

Cyclist0108

I wonder why mine is 128 rather than 126, given its date of birth (the bike is 1987, but the frame might be a year or so newer -- it was a warranty replacement for one I cracked).

L134 

. The all thread method is totally stupid.


Why?

easyupbug 

Ah, the misguided Reynolds 753 cold set myth. I say this to keep 753 frames from being scraped as they are lovely rides.

Yes, I know the Reynolds engineers placed a warning not to cold set and the internet repeats. Being a mechanical engineer I know how wrong engineers can be and how a skilled and experienced craftsman can do wonders.

So when I rescued a 753r frame with slightly bent forks and a slightly bent frame I gave it a try. Got the forks lined up pretty straight on my cast iron table but as soon as I mounted the bike and started riding I was back to dangerous pulling left and the same bent forks. I am slow so did this three times .

Took the frame to our local builder and he said no worries, back in the day we cold set these all the time. Mounted on
his Marchetti table imported from Italy the frame was straightened and the fork likewise on his custom fork table.
The bike rides beautifully.

TimmyT 

See my post above. If the only tools you have are a ruler and string, then it's better than eyeballing it. I wouldn't call it totally stupid.

Salamandrine 

Because usually one stay will require much more force to bend the same distance than the other. If you just push them against each other, typically the drive side will move out, the non drive side will nearly stay put, and they will be misaligned. At this point a lever is needed anyway. Better to start with one.

Salamandrine 

A ruler and string works fine. That has nothing to do with all thread.

L134 

OK, thanks. I guess that makes sense. I already did mine with the all thread method and it seemed to work ok so I was curious. Somehow seemed less primitive than Brown's method. Checked the alignment with the Park tool and it isn't perfect but close enough that I wasn't confident I could do better with more work or any other method. Bike rides well.

Had my main ride done years ago by LBS and the alignment is perfect. I just wanted to see what I could do myself on another bike. I'm happy.

dailycommute

Just did a diy cold set on 88 trek 560 (126mm) to approx 132mm for a 135mm hub. The last 3mm is easily done by hand on rear swap out so I left the diy cold set at 3mm per side. Used a stout straight piece of wood as per sb method. If you can easily swap in the wheel I would not bother cold setting, otherwise it does not take much leverage to move it 2mm per side.

rjhammett

I have a frame that I am going to cold set (126-130). I plan on using this method:
Cold Setting A Bike Frame (126mm to 130mm Hub Spacing)

fietsbob

OCD, & need absolute precision? then a frame builder with a Precision Frame Alignment table is where you need to go.

Those tables with the indicators etc. cost a grand+ , so expect it to be un free..

easyupbug 

+1, that 753r frame & fork straightening and 130 cold set was $80, 3 years and 1,000s of sweet miles ago.

L134 

Curious, I went back and measured. Sure enough, drive side out maybe 2-2.1mm farther than non-drive side (more than I remembered). Perhaps I'll go back and try to tighten things up but not now. Assuming frame was aligned when I started (I didn't check) drive side moved 3mm and non-drive 1mm?

andr0id

Depends on where and how you want to ride it.

$50 is a pretty good deal if you're planning on descending at 40+ mph and don't want a speed wobble.
For tooling around town, it doesn't matter.

The problem with "just spreading it" is that you don't really know which side is moving and how much. You could get one side (likely the NDS since is is not usually dimpled) stay straight, and all the shift be on one side.

Chrome Molly

Have had at least a dozen bikes that haven't been cold set from 126 to 130 and have never experienced a speed wobble using 130mm wheels (on several 35-40mph descents). 4mm of play here, even if it's 1mm on one side and 3mm on the other, I doubt anyone would notice a 3mm (as extended) misalignment across a 1040mm wheelbase (that's probably something less than 0.2 degrees for you to make up in steering, assuming that is perfectly aligned). Chances are your stem is misaligned by at least that, and that's on the input side of the riding experience. Still concerned about it, then spin your dropout adjuster screw maybe half a turn...

zazenzach

Coldsetting is such an easy and safe procedure. Using a jig is completely unnecessary.

Use the tools and method outlined in the following video:

Fivethumbs

I have an old magazine from 1989 with an interview of someone from Shimano right after Shimano introduced 8 speed Dura Ace. At the time all frames were built with 126mm dropout spacing. The first generation 8 speed Shimano rear hubs were 130mm so they came with a convex washer that would act to spread the rear triangle as you pulled the rear wheel in. At the time it was not considered an issue for steel or aluminum frames because 2mm is minimal. I have one frame that I cold set using the Sheldon Brown method and another bike that I did not cold set but just pulled the dropouts apart while pulling the wheel in. Either way is fine. If you don't cold set the triangle it does not take much effort to get the rear wheel in, just slight pressure on the dropouts with your thumbs while you pull the hub back with your index fingers.

gugie 

Being a mechanical engineer I know how the lawyers make them do things that don't make any sense whatsoever.

Exhibit A, lawyer lips.

gugie 

Having cold set many a frame, I can tell you that if the drive side stay is dented for a chainring, and you try to bend both sides at the same time, you'll only bend the drive side. If there's a dent on both sides for wheel clearance only, they'll probably bend symmetric in the same method,but sometimes there's a small difference in the dent. With no indentation, I've noticed that you can bend both sides symmetric.

At any rate, start with lower force than you think will effect a bend, and sneak up on it. The risk in cold setting is creasing the material.

gugie 

This is one of those threads where just about everyone is correct.

Being able to get the rear wheel in and out easily is the reason for cold setting. 10 speed shift systems, which I have zero experience in, apparently are much more sensitive to alignment, I would imagine especially the derailer hanger. Cold setting is fairly easy to learn how to do. The string method is "close enough", but not as accurate as a frame alignment gauge, which in turn is not as accurate as a flat table. Rear end alignment is over-rated - and this is what I hear over and over again from many a professional framebuilder, and is what UBI teaches at their framebuilding classes. On the other hand, if you can make it perfect, why not? For those who would never want to attempt this, don't. Why try something you're not comfortable doing, especially when it doesn't cost that much to have a competent bike shop do it for you - and you're supporting that LBS. For those who want to try it, by all means, do so, carefully, and you'll probably come out all right.

Follow your bliss, choose your path.

easyupbug 

Point taken, however, perhaps not so much in this case.

The following article is copied from a March 11,1983 issue of Velonews reporting on the NYC International Cycle Show of that year. (thanks Mike Richardson)
"Too-tough tubing"

Have you ever heard that a frame made of Reynolds 753 tubing can't be "cold set" (i.e.bent back into alignment after being twisted in a crash)? Is it true? If so, how come? We asked TI Reynolds Show representative TOM FIELD.

"No way" is now Field described the chance of cold setting 753. "You just can't budge it at all. In fact, once it's jigged and brazed you just can't change it. It must be perfectly aligned by the framebuilder and that's why we are so careful about who is allowed to build with 753."

Field said that any framebuilder who wants to use 753 is sent a test kit containing tubes, a bottom bracket, silver solder, flux and instructions. He assembles the parts and returns them to the TI Raleigh lab in England, where five tests determine his proficiency. Field said about half of the 753 applicants are refused permission to abtain and use the tubing. He said that the U.S. now has five qualified 753 framebuilders.

So what happens if a 753 frame is crashed out of alignment? First, Field said, since 753 is the strongest bike tubing in the world(diameter for diameter), it is the most resistant to bending in a fall. However, it tends to dent easier than other tubings because it is so thin; the center portion is only 0.3mm thick, or about three times the thickness of one Velo-news page. Once a 753 frame is actually bent, it is a major undertaking to make it right again.

"The builder must be very good with his torch, use a slow flame to heat the part, then replace the tube or realign the frame, as necessary," Field said. He added that the expense of this type of repair makes 753 "not the best choice for the younger or less-than-serious rider.

"Reynolds 753 is for the discerning rider," Field summed up. "It is so light and so stiff that the serious competitor can't afford not to have it."

Weight of the 753 road set is 1,800 grams. The track set is 1,750 grams.