Capt. Kirk

Hi,
I recently purchased a used 1999 Cannondale M300 SRB and I'm converting it to a gravel bike. I've put out a question to Cannondale but have not gotten a response from them. Does anyone know what these screws are for? This is the support bar connecting the seat post to the drop outs behind the seat post. I'm thinking it is for a rear cargo rack, but if they are for a rear cable stop, I'd like to see where I can get one of these cable stops. I bought a seat post cablestop for now.

To convert this to a gravel bike, I'll have to convert to cantilevers... thus the question.

Thanks,
Kirk

mstateglfr 

Those bolts are for a rear rack. Just keep them in place if you dont use a rack so that water doesnt get into the tubes.

That design is called a wishbone seatstay. Seatstays are the 2 tubes that connect the top of the seat tube to the rear dropouts. A modification to that is to have a single tube connect with the top of the seat tube, like you have. It looks like a wishbone.
Also, you do not need to get cantilever brakes. You can keep the brakes you have and buy TRAVEL AGENTS which will allow the V brakes to work with road brake levers. Another option would be to purchase miniV brakes as they have the same short pull ratio as road brake levers.
I mention these two options because they allow you to either use the brakes you have and/or avoid cantilevers.
If you are deadset on cantilever brakes, then get this CABLE STOP or something like it. It connects to your seatpost binder bolt.

Trakhak

When I buy a used bike with rack bolts or bottle cage bolts, especially an aluminum bike with rivnots with potential aluminum/steel interface corrosion like those pictured, I back the bolts out, grease them, and thread them back in. To avoid damaging the rivnuts in an aluminum frame, I twist the Allen wrench quickly but with minimal pressure.

The alternative method, i.e., applying slowly increasing force to the bolt, sometimes leaves the bolt stuck in the rivnut such that the rivnut turns in the frame tube rather than the bolt breaking loose of the rivnut. That's relatively easy to repair, but it's better to circumvent the problem.

Capt. Kirk

Thanks. I was hoping it was for a special cable stop mount, but it makes sense that it's for a rear rack. I've already ordered the cantis so I've committed to it. I'll definitely keep the original V brakes and if at some point i want to go back to original, I'll get the travel agents. Great suggestion!

I'll back the screws out, grease them and screw them back in. They were loose when I got it..one of many problems with the bike but it's coming along.

Thanks all,
Kirk

fishboat

A buddy of mine has a M700 with the wishbone seatstay. He used the adapter below to help in mounting a rear rack. Amazon has it (search rear rack mount adapter). The second pic is a surly cable stop. I've used these on a couple builds. The nice thing about it is the adjustment ability. It helps in setting up some canti brakes(pads with a threadless pole).

Capt. Kirk

Thanks Fishboat. I almost bought the Surly cable stop. Instead I bought a shimano Rear Centerpull Brake Cable Hanger With QR. It's a two prong adapter that is threaded through the bolt and attaches on the outside of the seat clamp. The spacing between the bolt and the clamp gap is very narrow and I find the ones that have a single hole that fits in between the clamp sometimes impede the clamp from closing tightly. It should be arriving soon, so I can't wait to try it out.