Random Tandem

Recently, I have had curiously good luck when it comes to Miyata bikes from 1991. Last year, I found my 1000LT at a very good price and the potential problems all melted away and I was able to set it up as my go-to long-range touring bike that I rode over the Washington Pass from Vancouver, BC to Spokane, WA (highly recommended 5 day tour).
Last month, one of my riding buddies decided he would add a steel touring bike to his mostly carbon-based stable. I found him another 1991 1000LT in near-perfect condition, but it turned out to me one size too small, so he bought it for his partner. The next week I found a small size 1991 Miyata Triple Cross (made in Taiwan by Dodson, but with Miyata splined triple butted tubing) at a near give-away price that I have set up as a bike for guests to ride when visiting me in Vancouver (and it seems to be a reasonable touring rig, for guests who want to roll around a little more). But I was still looking for a 21” steel touring frame for my friend...until this week, when I came upon this frame lying out with the trash!


1991 Miyata frame found on a trash pile

A quick look let me to try and see beneath the sloppy rattlecan job to see that the fork crowns had “Miyata” pantographs and the canti brake posts (but no chain protector, so not a 1000LT), so I wondered about a 600 series Miyata. After using some paint remover on the BB, I confirmed that its serial number (TAxxxxx) matched the Miyata pattern and indicated yet another 1991. As I was unable to find a 1991 catalogue, I reviewed the spec sheet page posted online and see that 1990 was the last year the 600GT was listed. The details on the frame do not match any of the other bikes listed in 1991 catalogue, but seems to perfectly match the 1990 600GT. Since there were no identifying components and I cannot see any sign of the original paint colour, I am left with the quandry – did Miyata keep making the 600GT after 1990, but not list them in the 1991 catalogue? Here are a few more pix of the details on this frame in case you think this must be a different model (I have confirmed that it is a steel frame and fork):

Hard to see Miyata pantograph on fork crown

Unhappy treatment of that cable stop

Just a BB

Which bring me to my real issue: the derailleur hanger on the right dropout has been damaged and I am wondering what to do. As you may be able to see in the photo below, the derailleur attachment hole has been drilled out so that it is no longer threaded and is about 12mm diameter.

Abused derailleur hanger

Obviously, the hanger is weaker than it was, but it may be strong enough to work. Nonetheless, the hole is too large and will no longer hold a bolt tight to attach the derailleur. There is another less significant injury to the frame on the bridge to stop the rear brake housing (shown in the third photo above) that will require some attention from a torch, but this is a less crucial issue than the derailleur hanger. I am planning to ask a frame builder about the repair (that will be paid for by my friend who will receive the bike), but I am interested in what others may think is the best approach before I proceed.

Thanks for your thoughts,

-Will

bark_eater 

The derailleur hanger may have already been bored out for a "Dropout Saver"

https://wheelsmfg.com/presses-tools/dropout-savers.html

Maybe you could solder one in?

Random Tandem

BE: I think you are right. I used a 15/32" drill bit to confirm that this is the diameter of the hole, so likely enlarged to deal with stripped threads. I will see if I can find one of the inserts at an LBS near me. I expect that there is enough of the dropout left that with the wider flange of the dropout saver insert it will hold the derailleur in place (so not necessary to solder, braze or weld it in). Thanks for the help!

-Will

The Golden Boy 

That creeps me out with the metal being so thin on that dropout hanger. With all the hipster dropout grinding 10 years ago- has there been a consensus as the best way to repair a missing hanger? A bolt on? Braze on a new hanger? Replace dropout?

I'd want to start from scratch, rather than that- and you can get the cable hanger repaired at the same time!

scarlson 

Never heard of that dropout saver - looks like a neat solution! I was going to say I'd turn something on the lathe to either fit tightly or braze in there, but if you have a ready-made thing, all the better. Braze it in with Harris Safety-Silv 56%, or just leave it tightened with the derailleur. It will definitely be strong enough if it's brazed in, and likely even if you just screw it to the derailleur. If you fill a hole perfectly, or near perfectly, the metal around the hole will be made more durable because it doesn't have to resist buckling or twisting. So even something thin like that will stand up to the forces a derailleur would put on it. If you're really concerned afterwards, you could buy one of those horseshoe shaped MTB derailleur guards.

The cable housing stop is a little harder, but still easy work to braze a new housing stop with silver and some vise grips or a spoke and a screw to position things.

This isn't rocket science. You could probably do what you need with a cheap swirl-flame torch, and learn something in the process. Total outlay including the torch would be under $100 to DIY. Use some wet rags around the paint up on the stays to protect the paint.

Bianchigirll 

I'd look around for someone to fix it properly. The paint is already so so from the rattlecan. I am no Smitty nor trained in the arts of metallurgy but I don't think it would take too much heat to fix them both. You might even consider getting the seat binder ears cleaned up a bit too.

tyrion

FWIW you don't need the cable stop if you use V-brakes.

John Nolan 

Or, just use one of the cable stops that attaches to the seat binder bolt.

Random Tandem

Thanks for all the advice. I am going to be looking around to see if I can get my hands on one of the dropout savers locally, otherwise I can buy one online. Looking at the dropout and a 15/32" drill bit, it seems very likely that it was drilled out for one of these, but perhaps the person drilling was not careful and the hole ended up more toward the edge of the dropout. I will test to see how tight the derailleur holds the dropout saver and whether it feels sufficiently stable, with a plan to have the dropout saver brazed in if it feels like it needs additional strength. On the cable stop, I will plan to have it brazed eventually, but in the meantime I can just use an alternate cable stop (I am pretty fond of cantilever brakes on touring bikes, so less inclined to linear pull). The binder bolt ears look ugly, but mostly I think this is the thick paint from the rattlecan job, and the metal is okay.

With this you have all given me a clear path to get this bike rolling, and allow my friend to take it on a tour in the spring and confirm it suits him, but that brings me back to my first question: did Miyata make the 600GT in 1991 (despite it not being listed on the 1991 spec sheet), or is this frame some other model or what?

-Will

TiHabanero

Take the frame with you to the LBS when you go on the hunt for the dropout saver. They come in three depths, and you need to match the depth to your dropout thickness.

nlerner

FWIW, I’ve seen a couple of Miyata 210 models with canti brakes, I think available in that configuration for just one or two model years, iirc.

Random Tandem

I have a little more information: it seems that this frame was originally painted black (the steerer tube was painted this colour and that would be an unlikely place for rattlecanning), which only adds to the mysteriousness, as this does not seem to be a colour in which the 600GT was offered in the relevant period. Moreover, the combination of (1) a 1991 serial number (in the form "TAxxxxx"), (2) horizontal rear dropouts, and (3) cantilever brake posts does not seem to match any of the catalog listings for 1991 or 1992 (I even obtained an almost complete copy of the 1991 Miyata catalog as part of my research). I also checked the 1991 and 1992 Koga Miyata catologs, which do not seem to include any other bikes that fit these three criteria. The frame characteristics do seem to match completely the 1990 600GT (including different cantilever posts on the rear forks vs. the front forks), other than the paint colour. Which leaves me with the conclusion that Miyata must have still been manufacturing 600GT frames in early 1991 and eventually painted and sold those frames, even though they were no longer listed in the 1991 catalog, and mine was one of those. I recall this was a tumultuous period for Japanese industry given the Yen revaluation and it was also a time when mass consuming bicycling was moving away from touring road bikes, so perhaps my frame was just one of the last orphans of dying species. I am so pleased that I am able to give a new lease on life and glorification!

As I progress with the frame "repairs" and building the bike, I will post more in the next couple months.

-Will