Need help identifying frame - is this worth saving?
 

Haven't a clue, but it came with high end parts; Stronglight needle headset, Mavic wheels, Sugino AT triple crankset, etc. ,though they could had been added on. Serial number starts with a 'T', the rest are numbers (around 5 digits), but the cable routes under the bb may be obscuring a couple. The fork tube has a split where it appears the stem was over-tightened and someone hacked off the rear brake stop and replaced it with a hanger-type. The frame is fairly light-weight, bottle bosses under the downtube makes it unique, which I remember that Specialized and Miyata did this.

I would save it. Looks Japanese: Miyata, SR, Nishiki,......

Find a replacement fork, though. Thrown the split one in the trash.

The third set of bottle braze-ons was a sign of a touring frame, as are the cantilever brake studs.

I don't know the frame, but the rear rack mount points on the seat stays doesn't look very common to me, and may help someone identify the frame.

I would hop over to C&V to get people that know quite a bit about older frames.

And other than the steering tube, definitely worth saving. Depending on which frame it ends up being, I would possibly even see about replacing the steering tube to keep the fork.

Nothing really unique about bottle bosses on the bottom of the downtube, it is pretty common for touring frames to have them. Certainly my Bertrand has them. Pity about the fork, if you can't get it repaired it will have to be replaced. The frame is well worth using if you can repair or replace the fork

I'd save it. Most definitely. Looks like a mid-80's Japanese touring frame and the parts wouldn't be out of place on it. Shame about the fork, but a new one is relatively cheap.

if you like late 70's early 80's steel full-on touring frames with canti's that one might be a nice one to have powdercoated and fixed up. i find my '79 trek 710 to still compare favorably to my latest carbon creations. a used 1" threaded carbon fork would be nice if the one on the frame proves impossible to have repaired, which i would try to do. looks like someone may have been a bit over-aggressive in tightening the stem bolt! :eek: if so, and in his or her defense, it looks as though the steerer has been threaded too far down. it has three times the threading on it as my original 85 trek steel fork has on it.

can't be sure, but it looks like there are no water bottle mounts on the seattube.

will a nut still thread down over it, or is it spread?

that's an idea worth considering, perhaps having a nut to sleeve over it will prevent it from splitting more.

Not an exceptionally high end frame, but interesting nonetheless. How much does it weigh?

You might be able to replace the steer tube, but you might consider drilling the top and bottom of the crack. I like the idea of threading something down onto whatever part is hidden within the headtube.

The groove is necessary for the cable stop for the center pivot/cantilever brakes.

The crack is likely caused by overzealous tightening of the handlebar stem.

Unfortunately, without reinforcement, the handlebar stem will continue to expand the crack, causing the handlebars to loosen. Get enough nuts in the right place, and perhaps this could be prevented as long as they didn't interfere with the steer tube clearance.

Actually sleeving it will be tough. The head tube is about 1 1/4" ID. Your steer tube is 1" OD, giving you about 1/8" clearance on each side for the sleeve. And with the existing spread of the crack, it will be tight to thread anything onto it.

What I would try is to take a couple of generic top nuts from cheap headsets. Cut them flat on top with threads to the top.

FIRST Mount the lower cone, race, and bearing to the steer tube.

Now, carefully thread the modified nuts onto the steer tube so they end lower than the mount point for the upper race.

Grind the nuts round.

Assemble and hope for the best.

Well, I'll agree with the idea of having a new steerer tube fit to that fork, but not replacing it with carbon. You'll likely lose the cantilever brake posts and the low-rider front rack mounts, which should be preserved on this bike. Have the fork repaired, or find a comparable era touring fork. PG

Measure those cantilever studs. There are two standards, and the modern one is farther apart. It might be 60 vs 80 mm or something like that -- check it against a newer frame if you can.

If, as I suspect, this frame has the old standard for canti studs, it's tougher to find a brake that will work well. And vintage cantis, like old MAFACs can cost a fortune.

So, here's one possible way forward:

Throw out the fork.

Get a new 1" fork at a bike swap for $20 to $40 that either has a drilled bridge for a brake or modern canti stud spacing.

Run it with a front brake, fixed rear. Don't spend more than $200 or so making it a ride able six-pack hauler with a rack on the back.

Or just ditch it. It's not the kind of frame you want to be agonizing over.

Moved from Mechanics

Replacing the fork steerer isn't such a big deal. I'd investigate that first. Definitely save the frame, probably save the fork. Looks to me like it'll take pretty fat tires, which is nice.

I've been led to believe that with lugged forks you have to replace the steerer and crown simultaneously as they're one piece.

The steer tube should be brazed to the crown.
Just like the fork blades are brazed to the crown.

I saw a super-wide fork with a crown at the local bike recycler today. None of the extra braze-ons, but if you need a fork to take wide tires, I can try to get some more info.

"When you hear hoof beats - think horse not zebras..." In other words seek out the simplest answer or solution to a problem first!

I wouldn't mess around with a steerer with a crack in it like yours. There's an increased chance that the threaded area of the steerer could break off. There's nothing more derrière clinching than riding down the street with detached bars in your hands. Been there - done that! :eek:

The reason why the steerer cracked the way it did is that the threaded section is as much as 2" too long. Some bike makers did this to save money. They could use the same fork on a number of different size frames by just cutting the steerer off to the required length.

Ideally a stem should be inserted about 75mm to 80mm into the steerer - many stems have a minimum insertion mark. In the case of your fork the stem wedge expanded in the threaded section causing it to split!

A competent frame builder can cut off the top threaded portion of the steerer and TIG weld a new threaded section on. If well done it will be as strong as the original steerer. It wont damage the paint.

The second option is to have a frame builder replace the whole steerer. This will damage the paint and probably cost you a lot more.

Finally you could get a replacement fork but finding one with the cantilever studs and the correct steerer length, blade length and fork rake is going to be difficult.

The fork and steerer are the most highly stressed parts of a bike frame.

Forget about the shade tree mechanic suggestions unless you have good heath insurance and are VERY lucky! :notamused:

BTW I used to build and repair frames and I hang out with a few local frame builders who do these repairs all the time...


verktyg :50:

Chas.

It isn't my money so in a purely selfish manner, yes. Replace the steerer and get it repainted. Then in a few weeks or months post back and everyone will ooh and ahh over it.

hells yeah: easy fix for the competent frame shop to splice on a new steerer, and then you have a perfectly serviceable touring frame with a lot of nice components.
Bernie Mikkelsen used to charge $60 to do this repair (correctly and accurately!) and even if his price has increased it's still cheaper than a fork that would match that one.