upgrading late 80s cannondale with 11 speed components

[CAP57]

I am building up a late 80s cannondale with modern ultegra R8000 components and I am wondering what is the best way to route the cables. (the spacing for the rear wheel measures out at just over 127mm and I was able to fit a 130mm wheel in without stressing the frame)

I would like to get a Cannondale boss kit and attach housing stops on the downtube. I found this replacement boss kit on eBay. Is it possible to attach this without stripping down the paint and epoxying them on? Are there any other alternative options to getting housing stops on the downtube? clamp on stops?

The chainstay is also missing a housing stop for the RD but I am not sure what the part would be called or what exactly I am looking for. Would anyone happen to know the name of this missing part or anything I can use as a replacement? Should I look into stick on/zip tie cable stops?

I would like to attach a braze on FD using the holes provided on the frame. Am I just looking for something like this braze on plate to attach to the frame? Looking at the one pictured it does not seem like it would put the FD in the correct place.

If the above options do not work out. Is routing the bike with zipties going to affect shifting/brake quality?

Thanks in advance!

 

[black lightning 1987]

I would recommend that you find the Cannondale parts from a trashed donor frame. Keep an eye on local craigslist and contact your local bike co-op for leads. The linked front derailleur mount might work but you would have to assume the guinea pig role to find out. I can't see the down tube bosses working at all. If they had made one side in two pieces like the original so they could be tightened without rotating the concave bits that contact the down tube they might be OK. I doubt you could find clamp on stops with the right diameter clamp. Here is what the original bits look like:

 

[black lightning 1987]

The gold portion of the down tube boss rotates independently of the concave boss, so that allows the assembly to tighten up without damage to the tube. You put the fixed boss and threaded rod through one side of the tube, add the boss for the other side, and tighten the gold "nut" to bring everything tight.

 

[black lightning 1987]

Looks like someone has run full length housing all the way to the rear derailleur but I can't imagine that it doesn't affect shifting performance. SunTour made some clamp on front derailleurs with a cable housing stop but I doubt that they would shift Shimano 11 accurately.

 

[black lightning 1987]

The chain stay housing stop is made from a piece of steel about 1/16" thick. It is attached to the stay with two pop rivets. If you are handy you could probably fabricate a replica. I can get you a picture of the original if needed.

Ask around your local bike shops about shops that were Cannondale dealers in the 80s/90s. Some local shop may still have a box full of these frame attachments. All the dealers would have had them when the bikes were relatively current, but most of the vintage Cannondale dealers are long gone.

 

[CAP57]

The gold portion of the down tube boss rotates independently of the concave boss, so that allows the assembly to tighten up without damage to the tube. You put the fixed boss and threaded rod through one side of the tube, add the boss for the other side, and tighten the gold "nut" to bring everything tight.

Thanks for the reply! Is there a range I should be looking to pay for an oem cannondale boss kit? How much should I be looking to spend on a used frame? I see quite a few used cheap cannondales for sale but it seems like such a waste to part out a perfectly good bike to build this one. If I bought something like this would it be fairly easy to take these parts out? Do I need any proprietary tools to do the job? Something like this would be perfect. Thanks again!

 

[black lightning 1987]

No special tools required, just a proper sized drill bit to drill out the rivets on the chainstay stop (start small). Adjustable wrench will remove the down tube bosses. Just be careful to loosen the correct side. The fixed side boss is diecast and pretty delicate. The one in my picture has the threaded part that holds the central rod broken off from the boss. Best to soak the rotating side well with a good penetrating oil so that you don't have to apply too much torque to break it loose. Front derailleur mount is just two socket head cap screws, 4 or 5 mm hex wrench to remove. Shoot some penetrating oil down the seat tube and around the mount. If the rivnuts turn in the frame you will have to drill or grind the heads off the cap screws, but not something I've needed to do. That 1987 SR400 would be a good candidate if it were in rough shape. Bottom of the line road bike and the Alpha 3000 components aren't much. I'd be patient and look for a rough/damaged frame.

 

[CAP57]

No special tools required, just a proper sized drill bit to drill out the rivets on the chainstay stop (start small). Adjustable wrench will remove the down tube bosses. Just be careful to loosen the correct side. The fixed side boss is diecast and pretty delicate. The one in my picture has the threaded part that holds the central rod broken off from the boss. Best to soak the rotating side well with a good penetrating oil so that you don't have to apply too much torque to break it loose. Front derailleur mount is just two socket head cap screws, 4 or 5 mm hex wrench to remove. Shoot some penetrating oil down the seat tube and around the mount. If the rivnuts turn in the frame you will have to drill or grind the heads off the cap screws, but not something I've needed to do. That 1987 SR400 would be a good candidate if it were in rough shape. Bottom of the line road bike and the Alpha 3000 components aren't much. I'd be patient and look for a rough/damaged frame.

The bottom of my chainstay looks like this. Would I need to drill into this still? Any recommendations on oil to soak with? If I were to buy a frame and strip it, is the frame essentially useless without those parts? I would be happy to donate the stripped frame to a bike coop if they can use it.

 

[black lightning 1987]

I was thinking that the 1987 frame I looked at had the two rivet holes (nearly) parallel with the rear wheel axle - in line at 90 degrees to the centerline of the stay. Those look to be staggered - kind of on a diagonal to the centerline of the stay. I have a couple of 1988 frames and some older ones I can check given time. Check your serial number and see what the build date is.

 

[CAP57]

I was thinking that the 1987 frame I looked at had the two rivet holes (nearly) parallel with the rear wheel axle - in line at 90 degrees to the centerline of the stay. Those look to be staggered - kind of on a diagonal to the centerline of the stay. I have a couple of 1988 frames and some older ones I can check given time. Check your serial number and see what the build date is.

Unfortunately this frame doesn't have a serial number. I was told it was a gift from someone who worked at cannondale. It seems like I am doing a disservice building this frame up if I have to part out another just to put modern components on this one. Would I be better off finding a different frame to build?

 

[black lightning 1987]

Kroil has a reputation as being the best penetrating oil but it's expensive and you usually can't find it locally. PB Blaster has a pretty good reputation and is easy to find.

You can sometimes pick up framesets for less than the fork is worth so there is value there. These frames could be made into a single speed/fixed gear although it would require a chain tensioner or eccentric bottom bracket. But people do that, so the frame wouldn't necessarily be scrap after losing the fittings. And there is always the chance of finding someone who has a cracked/dented frame with all the fittings that just needs good tubes.

 

[CAP57]

Hmm thanks again that gives me some peace of mind. Do you think something like this would work for a chain stay stop?

NOS Shimano Chainstay Cable Guide with Housing Stop from the 80s

Weight/Gewicht : 10 gr Condition: New old Stock (NOS)Diameter / Durchmesser:13.5 - 15.5 mm Production date / Produktionszeitraum : 1980s

www.velosaloon.com

 

[black lightning 1987]

Unfortunately this frame doesn't have a serial number. I was told it was a gift from someone who worked at cannondale. It seems like I am doing a disservice building this frame up if I have to part out another just to put modern components on this one. Would I be better off finding a different frame to build?

Certainly something to consider. There are lots of options out there for vintage frames - all materials and brands. Don't know what your priorities are.

 

[CAP57]

Certainly something to consider. There are lots of options out there for vintage frames - all materials and brands. Don't know what your priorities are.

Thanks for all the info. This really gives me something to think about. If I do decide on building this frame up, the individual parts I am looking for are chain stay housing stop, fd plate, boss kit and boss covers? Is there anything else I am missing to complete the frame? Are stick on cable stops with zip ties at all worth looking into?

 

[black lightning 1987]

Hmm thanks again that gives me some peace of mind. Do you think something like this would work for a chain stay stop?

NOS Shimano Chainstay Cable Guide with Housing Stop from the 80s

Weight/Gewicht : 10 gr Condition: New old Stock (NOS)Diameter / Durchmesser:13.5 - 15.5 mm Production date / Produktionszeitraum : 1980s

www.velosaloon.com

I never measured the stay diameter of an early Cannondale but my guess is that it's at least 20 mm so that clamp would be way too small. You could probably drill some holes in that stop and rivet it to the frame, but I wouldn't want to add more holes to the stays, especially if they were near the existing ones.

 

[black lightning 1987]

Thanks for all the info. This really gives me something to think about. If I do decide on building this frame up, the individual parts I am looking for are chain stay housing stop, fd plate, boss kit and boss covers? Is there anything else I am missing to complete the frame? Are stick on cable stops with zip ties at all worth looking into?

From what I can see, that should cover what you need to cable the frame. I haven't seen the stops you mentioned but derailleur cable tension and be pretty high. Back in the 1970s when everything was attached by clamps, frame builders used to braze a small piece of steel to the underside of the down tube to keep the shifter clamp from moving under cable tension. That makes me a bit apprehensive about recommending an adhesive stop and a zip tie for a similar purpose.

 

[CAP57]

I never measured the stay diameter of an early Cannondale but my guess is that it's at least 20 mm so that clamp would be way too small. You could probably drill some holes in that stop and rivet it to the frame, but I wouldn't want to add more holes to the stays, especially if they were near the existing one

Yeah this makes me feel like I should build it out properly. I am a little apprehensive when you mentioned I need to drill out rivets. This would be drilling into the chain stay of the doner frame to take out the piece I need?

 

[CAP57]

Thanks for all the help yesterday. Here is some progress as the parts come in. Next is the tricky part of routing the cables! Any thoughts on clearance with the derailleur hanger and the high gear? It looks like theres somewhere between 1-3mm clearance there although I have put any cable tension yet.

 

[black lightning 1987]

Yeah this makes me feel like I should build it out properly. I am a little apprehensive when you mentioned I need to drill out rivets. This would be drilling into the chain stay of the doner frame to take out the piece I need?

Yes. I have never drilled any rivets out of these frames but my guess is that they are aluminum rivets with aluminum shanks, which should drill out pretty easily. Problem with drilling out rivets is that the drill will often want to drift off the center of the rivet into the gap between the rivet and the shank. Drilling there will result in an oval shaped hole in the frame, which may or may not be too large for a 2nd rivet to expand enough to anchor securely.

 

[black lightning 1987]

Thanks for all the help yesterday. Here is some progress as the parts come in. Next is the tricky part of routing the cables! Any thoughts on clearance with the derailleur hanger and the high gear? It looks like theres somewhere between 1-3mm clearance there although I have put any cable tension yet.

View attachment 9398View attachment 9399

By high gear do you mean the largest cog? That is actually the low gear - lowest gear ratio with a given chain ring. I can't see what model of derailleur you have but it looks to be something like a GS cage Shimano. I'd need to know model number of the derailleur and the tooth count of your cassette to give you a definite answer, but my guess is that you will be OK once you have the proper length chain and everything is adjusted correctly.