Wanted Downtube Shifter Boss / cable stop mounts

[RickG]

Restoring a 1994 H400.

The downtube shifter boss, AKA the place where the cable stops mount, completely failed when I tried to reinstall the cable stops. Hoping someone has one of these sitting around in a bin somewhere. Thanks in advance to anyone who may be able to help.

 

[black lightning 1987]

I have one that's probably broken in the same place as yours. See this thread for a pic and my thoughts on repairing them. Second link is for an aftermarket repair part.

http://community.vintagecannondale....shift-lever-boss-for-a-95-r300.254/#post-1338

https://www.cycle-frames.com/bicycle-frame-tubing/NOVA-LEVER-BOSS-KIT-FOR-AL-FRAME.html

 

[Brian]

Could you send me the failed one if you get a new one? I have been wanting to replicate this part, but its very tricky and very expensive to reproduce.

 

[black lightning 1987]

Brian, what about 3D printing? Might be a lot cheaper than the original die cast. I would make both sides the same as the right hand, with both sides having the steel part passing through the spacer that has the radius to fit the down tube. This would eliminate the threaded boss breaking off the pot metal on the left side, and eliminate making the left side altogether. I would put a 12 mm square boss (which the left side has) on the spacer instead of the 4 round bosses that index the shifter plate on the Cannondale part. You can't put a Campagnolo downtube rear shifter on these frames without modification as the 4 round bosses on the right side form a square too large for the Campagnolo lever stop plate. They put the four round bosses on to provide room for using a socket to tighten the steel part. The hexagon area on the steel part isn't even needed as you can tighten it with an adjustable wrench on the two flats. You should also consider making the flat back plates for Shimano shifters, as they are getting hard to find.

I can loan you my broken one if you want to pursue this.

 

[RickG]

So I have created a work around which, while it may not pass as a “restoration”, both works and doesn’t stand out as a patch job without a second look. The key is that the brass end of the original DT shift boss is still usable.

Parts - all bolts match thread pattern of the

• Original brass fixture
• Cable stops
• Generic curved DT shift boss (bought a pair at Framebuildersupply.com)

• Shimano SL-7800 shift lever boss cover
• 2” bolt (length may vary depending on frame diameter)
• .6” bolt
• .5” bolt (original)
• Old tube
• JD Weld steel formula
• Thread-lock

Instructions
I neatly cut the head off the bolt leaving a 1.5” threaded post. (Same length as my original post.) I attached the post to the generic shift boss with the JD Weld making sure not to thread it too deeply. Because the curve of the frame and shift boss don’t match exactly, I cut a gasket from the old tube to protect the frame. Thread the post through the frame and attach the brass fixture using JB Weld. Make sure not to over tighten.

Place the shimano cover over the generic boss stop and attach the cable stop using the.6” bolt. Install the cable stop on the brass fitting side with the original .5” bolt. Use thread lock on each.

The shimano cover is slightly thicker than the original covers. I ground the lip off the edge of this with my Dremel although it wasn’t entirely necessary. Removing the lip does help to keep the cable stop from rotating due to the square structure. I will clean this up better before final assembly. Regardless, the longer bolt was necessary due to the increased width.


Finished, this is attached solidly, isn’t rotating, and if the need arises it will be easy enough to drill out the generic shift boss end.

 

[Mr. Greg]

I'm having a very similar issue with my CAD2 R300 after having an accident in August. Mine broke shortly after the accident.



Any luck finding a downtube shift post/cable stop? I've been looking everywhere! Anyone have one that they are willing to part with?


ANY help (even pointing me in the right direction would be appreciated!

 

[black lightning 1987]

I would think you could JB Weld the stud back in the boss. I'd saw the broken part off the stud so that it can thread into the boss a bit more. With the epoxy it should hold as long as you are careful not to tighten it to much. If that doesn't work you can order one of these:

https://www.cycle-frames.com/LEVER-BOSS/

People who have used them say that you have to file them a bit to fit the larger than usual down tube of a Cannondale but that they work fine otherwise.

 

[Mr. Greg]

Thank you so much! That's really helpful.

Look what I just found on ebay right as you replied...

I guess you guys are good luck! I'm pretty sure this is exactly what I need, right?

 

[black lightning 1987]

What a find. That part's a pretty common request here as well as on other bike forums but the one you bought is the first factory replacement kit that I've seen. Pity that the seller doesn't have 50 of them.

 

[Mr. Greg]

Thank you, I was so surprised I found it! Here's the link to the shop that I bought it from on ebay.

https://www.ebay.com/usr/incycle-bicycles

I called them up to see if they had any other factory compatible parts kicking around... Apparently, they just cleaned out the back of one of their six shops and found a slew of old Cannondale parts that they are still sifting through and selling. Anyone looking might want to check them out or shoot them a ring. It's worth a shot.

https://www.incycle.com/

From what the manager told me... they are updating their own site to reflect ebay inventory and the "new - old" parts that aren't listed yet. Hope this helps others in the same situation!

 

[black lightning 1987]

Thanks. They don't have any more of the shifter kits but I will check their other items.

 

[Steve Zissou]

Hi!
Thanks for this tread, I already learned a lot!
I am looking for a part like this to mount my shimano 600 shifters on a frame that has nothing in place there.

I checked the links but could not find anything available. Can anyone help me on this?

Thanks!

 

[black lightning 1987]

Hi Steve. They are apparently not back in stock yet at cycle-frames. When I inquired I was told that they would have them back in at some point but it could be months down the road. You might check around at long term Cannondale dealers in Europe and see if any have the kit pictured above. I wish we had a list of dealers that existed in the 1980s and 1990s but I don't know of one. I know a couple of old dealers locally, will check with them.

 

[aquea]

Hi there, i'm new here, as i bought a second hand caad3 Saeco.

But after 2 weeks of riding, the downtube shifter boss broke.

I was looking for a solution and found this post.

It seems that the original piece is hard to find, and i can't find replacment one, my though is to shift this system... Does anybody try that?

Thanks

 

[black lightning 1987]

I am not sure what you are suggesting. I think that it might be possible to thread a small diameter aluminum tube to accept the screws for down tube cable adjusters. You would have to be careful not to over tighten them as you could distort the down tube. If I can find the time I might give this a try.

 

[black lightning 1987]

This is kind of pricey in my opinion but looks functional if a bit clunky.

https://www.ebay.com/itm/133573798543?hash=item1f199e6a8f:g:pjYAAOSwzJBgU3VD

For other tube diameters:

https://www.ebay.com/itm/154189864302?hash=item23e66e9d6e:g:2cQAAOSwCuBgU3dz