guy1138

I restored/refreshed a 1985 Miyata 610 last year. If you Google "1985 Miyata 610" my bike's Bike Index page is the first result. It has the Horizontal short dropouts, as seen on Sheldon Brown.

I can assure you, OP's is definitely sitting too far forward, especially since it doesn't have the "teeth" of the QR nut biting into the dropout. Also, yes, they did have a version with a "T-nut", but that was only on long set-back, flimsy stamped drop-outs. They never came specced on horizontal short forged dropouts.

Johnathonbenfie

However I think he stands too far away. The picture doesn't really convey how it stands.

guy1138

Amazing. It has a barrel adjuster threaded into the plate retaining hole. To secure a claw type RD into a forged dropout. An RD non-original to the bike. Installed in a way that is clearly dangerous.

Hondo, what are we even talking about here?!? Tell OP that it is hazardous, install literally *any* long cage RD, bend the hanger into ~place and move on! Jesus ******g Christ, am I on crazy pills!

I would 100% refuse to work on this bike in my shop for even a flat tire, if the owner refused to fix this setup. It is an injury waiting to happen, AS EVIDENCED in the first picture he posted where the driveside part of the axle slipped forward and the tire was clearly rubbing on the non-driveside chainstay!!! FFS

guy1138

Only six-speed SIS was Dura Ace ; this ain't dura ace.

Hondo6

Um, no. One example: Shimano 105, 1050 series - per Velobase, it was released Aug 1986 for catalog year 1987 and was originally 6 speed SIS; the 6-speed shifters were SL-1050. Shimano 600EX also had a 6-speed SIS version (shifters were SL-6208). The same is true for a number of other Shimano groupsets of that general time frame (mid-late 1980s).

Dura Ace was the first Shimano SIS groupset, and its first iteration was 6-speed. For a short while, it was the only SIS groupset - and in 1985, I believe it was. But it was hardly the only 6-speed SIS system Shimano ever made.

Hondo6

Perhaps you missed these parts of my comment above (emphasis added):

". . . . we don't know if the OPs bike has the correct nut or not. If not, that would likely be a problem."

"And even with the correct nut, I don't see how a derailleur adjusting barrel could be torqued tight enough by hand to hold the derailleur reliably in place. Replace the derailleur adjusting barrel with an M5 bolt and lock washer and it might be reliable."

I thought it obvious that one would need to use tools to torque down an M5 bolt enough to hold strongly, so I didn't mention using them.

I also don't see anything inherently unsafe about using a claw mount derailleur. They've been used for decades, and are still sold today - albeit generally on lower-end derailleurs.


Edited to add: you also might be interested in this article from Red Clover Components:

https://webcache.googleusercontent.c...=firefox-b-1-d

(It's a link to Google's cache of the article, so you may have to cut and paste the whole link into your browser to read it. Sometimes those links don't work properly on this forum's software.)

The use of a claw mounted derailleur on a bike with a derailleur hanger integral to the frame is covered in that article. It can be done, and done safely. And if you want to run a non-Simplex derailleur on a frame with an integral Simplex derailleur mount without modifying the frame, it's one of the few options available.

SpedFast

I would not want to have to fix a flat on that setup on the side of the road.

yesterbik

It really amazed me to read all of your great explanations and advice. I read/learn all carefully and agree that it needs a different type of derailleur, a direct mount one.
I checked the one on my bike, it's a Shimano RD-L541.
I will look on ebay and find a replacement and hope I can share everyone with a proper derailleur soon.
Thank you all and happy biking.

Mike

Chuck M 

While you are eBaying, you could look for the original equipment derailleur while you are at it. I did that for my wife's Bridgestone just because I wanted it to be as original as could be even though the bike isn't anything special. One, I knew it should work and two, I'm just weird like that.

SurferRosa

It's "silly" to setup a bike properly?

Hondo6

According to this online catalog, for the 1985 model the Miyata 610's original RD was a Shimano RD-L514 SGS; the shifters were L-412s. If the OP can find one, that would be good - but an RD-L541 is a close cousin and is from a few years later. Using that later RD (or another SIS-capable long-cage hangar mount model from the Light Action series) would similarly preserve the general vintage appearance, plus allow the OP to go SIS in the future should he decide to do so. They might also be easier to find - Velobase doesn't even list the 514, so it may be fairly rare.


Edited to add: however, if the OP wants to go original, this eBay seller has one that would match the original and looks to be in good condition for a reasonable price:

https://www.ebay.com/itm/255513224111

Since Shimano documentation (EV) for the RD-514 is dated Sep 1984, I'd take the "7/8 speed" and "SIS" claims in the listing with a grain of salt - though it's possible that the derailleur might actually work in those configurations, dunno. Regardless, it it does seem to be in very good condition.

I have not done business with the vendor, nor do I have any connection with them whatsoever.

Hondo6

Not at all. But neither is using a claw mount derailleur inherently silly or unsafe - assuming it's done properly. While it may be aesthetically unpleasant, it can be both functional and safe.

And as the article from Red Clover Components I linked above describes, if you have a vintage frame with an integral Simplex dropout hanger and need to mount a non-Simplex derailleur, it's the only choice you have that requires absolutely no frame alteration. That's not the OP's issue, but it could be an issue with some vintage frames.

yesterbik

Hello everyone,

I purchased a Shimano DEORE MT60. It looks similar with the old one, but direct mounted.
After put it on, all gears are working well.

Thank you all for your advice and comments.

Mike

Hondo6

Glad to see you got things sorted out and working well. Looks nice; enjoy.

And thanks for posting info about the final outcome re: your original inquiry. All too often that doesn't happen.

yesterbik

Thank you for helping newbie.
I can feel the improvement on changing gear as well.