SM600?

[Ergo]

The frame number is 18031788111, but I can’t figure out what it is.

Looking at the catalogs, the Suntour XCD derailleurs make it look like a 1989 SM 600.

This is the bike my wife rode in college in the early 1990s and I’m fixing it up for my son to take to college.

I’d like to update the derailleurs, since right now I can’t get the the chain to not hit the front derailleur cage in the lowest gear but it then hits the largest sprocket if I move the derailleur further down on the frame tube and there’s no barrel adjuster at the derailleur to make fine adjustments.

The rear derailleur has no B adjustment screw so I can’t get the chain to shift into the lowest gear without the chain rubbing on the upper jockey wheel.

Any suggestions for suitable derailleur upgrades?
Though looks like I’d have to use a derailleur hanger for most rear derailleur upgrades.

 

[letsbike]

That looks to be a 1988 SM600 that has seen some rough treatment.

 

[Ergo]

Agree, that’s the conclusion I’ve reached too. The wheels, derailleurs, brake are all stock, frame is straight and original paint. But I think a lot of it was left at various bike racks and railing in San Luis Obispo. I’m tempted to restore with the original shifters and red cable sheaths but my kid has shown minimal interest in it…just want to write code all day.
There is a broken tooth on the gear set and I might replace that if I find a suitable replacement

 

[black lightning 1987]

The rub on the large cog could be from incorrect chain length. Does it happen with all three chainrings?
My first Cannondale was a 1989 with XCD. I put almost 8000 miles on it with only replacing the chain a couple of times, and one freewheel. I don't recall either of the issues you're having. Could the front problem be incorrect limit screw adjustment? You could add an inline cable adjuster for fine cable tension adjustment. I have a box full of XCD stuff if you think something is simply worn out.

 

[Ergo]

I thought the same thing and just bought a new chain yesterday. The play on the RDR is fine but I got a couple of replacement jockey wheels out of my local ship’s parts box. We’ll see if that makes a difference. I’m gonna clean them up but don’t want to remove the finish.

I appreciate the offer!

 

[Ergo]

I thought the same thing and just bought a new chain yesterday. The play on the RDR is fine but I got a couple of replacement jockey wheels out of my local ship’s parts box. We’ll see if that makes a difference. I’m gonna clean them up but don’t want to remove the finish.

I appreciate the offer!

 

[Kenright73]

As previously stated, it's a 1988 SM600. Pictured below is mine, all stock except for tires, grips and Profile Bar Ends. I've only ever seen 2 being offered for sale; 1 became mine and is my daily street bike. So with yours, I guess that means there's 3 out there

 

[Kenright73]

If youre looking for parts, you should be able to find some 6 speed freewheels/cassettes on eBay. Shifters might be a little harder to find as they are a little unusual, as are the bat wing brake levers. I hate em, but love em. They're staying, even though I'd love to add another cog on the back....

Also, try this link. Top of page should say Vintage Components. Scroll down and click on the part you are looking for, etc. It's a little tedious, but these guys seem to have everything!!!! Best seen on a real screen, trust me on that. LMK how it works out!!

Vintage & Modern bicycle components from South Salem Cycleworks

A listing of vintage bicycle components

www.sscycleworks.com

 

[Ergo]

I found the exact freewheel on eBay, just finished painting and putting decals on. Now replacing wheel bearings.
Mine had a gloss black stem that looks stock, which I kind of like, but may go back to the red seat and stem at some point, but the red stem/seat is less than understated for my taste.