silos

Hello guys, I have a surly long haul trucker and the break looks like to be DIA COMP model DC980 (it is very similar)

One of the bolts that holds the cable for front break is damaged (the picture does not help too much but the bolt cannot be turned very tight because it loses its grip in the internal walls that hold the tool to turn it) . Now Im looking for ideas to replace this bolt since it looks like a very special bolt I never saw before.

If you guys know alternatives here I appreciate your help.

PS: Someone told me to buy the whole system new but I found this alternative very agressive with nature, since I just want a simple bolt and the other parts will not be used soon (my bike is new).

Thank you!


Since I cannot paste my pictures here, I hosted my picutres on this website: gist . github . com / gsilos / 88107a524e13859f7f67c2335195c685

Iride01 

https://gist.github.com/gsilos/88107...67c2335195c685


The OP's pics.

Juan el Boricua

Is there a bike coop nearby; LBS? See if they have a bin of old canti brakes for you to scavenge a cable pinch bolt. If not, maybe try to find a regular or nylock nut that can work on the male ("bolt") end of the pinch bolt. Good luck.

Iride01 

I find it hard from the pics to tell if it's the bolt or the threaded thing it screws into that is stripped. Though I lean toward the nut being stripped.

If it were me here in my country needing that, I'd first go to all the nearby bike shops and show them what my issue is and see if any go to their spare parts bins and either gives me a replacement or only ask a pittance for it.

If this is a fairly new bike, I'd also contact the manufacturer or their authorized reseller and see what they say or offer.

Certainly as a temp fix the suggestion of just putting a nut that fits on it might be an option, but I wonder if the bolt is actually long enough to extend through whatever it fits in judging from the parts you show.

If you are capable, you might drill a hole in a longer bolt and if it doesn't find sound threads in the original nut, then add another nut if it's long enough to extend completely through the original.

Drilling a hole in a bolt that is hardened might be difficult for some. Drilling a hole in a bolt that isn't hardened might leave you with something not having enough tensile strength to tighten it enough to hold the cable securely.

Crankycrank

A longshot would be to contact Dia Compe in Taiwan. They may be able to give you a part number or something helpful. What the heck, it's easy and free to just send them an email. CONTACT | DIA-COMPE

silos

Iride01, it is the nut that is causing this problem.

This nut has a format that I never saw before. It is totally special thing that I think only the vendor can provide. Someone here gave an idea of making a hole in a bolt... I will think about it.

Im trying to fight against this practice of this vendor to create special format of bolt and nuts by coming here and checking if group thinking can be a good option to fight against it. I added new pictures here to try to ilustrate how this bolt fits there... Let me know if these pictures can help to understand.


In here we see the bolt and the nut together.
gist . github . com / gsilos / 88107a524e13859f7f67c2335195c685#file-bolt-and-nut-inside-the-hole-jpg

Here we see just the bolt passing through the hole. We can se that there is a space that will be fitted by the cylindrical form that exists in the nut.
gist . github . com / gsilos / 88107a524e13859f7f67c2335195c685#file-bolt-inside-the-hole-jpg

and here we can see how the nut fits inside the hole. this nut has a head in a conic shape. it is empty inside. the damaged part is in the inside that I cannot anymore fit an hexagonal alen hey into it.
gist . github . com / gsilos / 88107a524e13859f7f67c2335195c685#file-nut-inside-the-hole-jpg

Im sorry for these weird links for my images. I still dont have permission to post images or normal URLs here.

Thank you for your attention and reply!

silos

Hi Juan, that is a good idea. I will try to find somethink like "bike cooperative" or "local bike shop" to check if they have something that can help. I live in Berlin btw.

Thank you!

silos

I tried it right after reading your message. Their website looks very slow. Here is what I saw in my browser :

This site can’t be reached

www.diacompe.com.tw took too long to respond.

I will keep trying. Anyways!

Thank you Crankycrank!

Juan el Boricua

Hope that there's one close enough to help. Good luck.

Iride01 

No need to apologize for the lack of permission to post pics and other stuff. Though many don't understand it, it's a good policy, one of many that assist with spam prevention. Especially on high volume sites like this one.

I'm impressed you took the initiative to figure out how to get around it. Surprisingly you'll see posts here from other newb's that just acquiesce to this policy or complain without having enough gumption and ingenuity to do what you did.

You have 10 posts now so that probably won't be an issue any more. At most you might have to wait another day before your status gets updated.

Now that I see the last pic, I don't like that design either, but it's unlikely Surly is going to change anytime soon that will help you in your current situation. However they might offer some remedy or just get you the replacement parts. Until then you still might do one of the other suggestions as a temporary fix. You should note that it appears their intention is that the bolt not actually tighten onto the cantilever, but remain loose enough for the whole thing to rotate to keep the cable straight as the brake pad moves toward the rim. Not sure how much of an issue it will be if your make something that can't do that.

silos

That is nice! Thank you!

I checked the rear break and I see this thing is completely stuck once the nut is tied to the bolt. So I dont think the format is what it is because it needs rotation once installed because I dont see this rotation in the rear break!

So with that observation, I imagine that there is a way to create a bolt at home my self just to keep the cable fixed there.

I already started doing an experiment here with some material to check if im able to produce this bolt myself.

I will give it a try and even if the result is ugly, at least I didn't spend 35 euro in a whole new system just because I want the bolt.


this was just to make sure I can create a hole in a new bolt. it worked fine. easier than I imagined! it is my first time doing this ahhahah

this is the tool I used... also first time using this stuff.

ClydeClydeson

Take a moment to evaluate the failure and see if you can't determine the cause before you move forward.

It is very unusual for a steel fastener to fail like that unless you (a) are vastly overtightening, or (b) are using a damaged or incorrect tool. For instance, if you were using an imperial hex wrench instead of the correct 5mm hex wrench, it is very likely to ruin the fastener. Same if you are using a very worn or damaged hex wrench.

While that particular fastener is not a common style, that is almost certainly not the cause of the failure. I'd bet my life savings of 0.35$ that the failure was caused by user error.

edit: Another possible factor in the failure is the round-head hex keys designed to allow the tool to be used at an angle to the fastener - these put a load on the inside of the fastener that is concentrated at the centre of the round head of the tool instead of along the whole length of the inside of the fastener.

dedhed

https://porkchopbmx.com/nos-dia-comp...antilever-nos/
Small Parts Service Parts for Dia Compe Gran Compe Superbe Calipers Royal Gran Compe Sidepull Brakes at Yellow Jersey

Or cut slots in the existing nut and use a big flat screwdriver.

dedhed

This looks like it may also be the same nut.

https://www.dchivey.com/index.php?ma...ducts_id=85655

silos

Hmm, carving the metal could be a possibility but since this nut is is empty inside, I dont think this is an easy task... you can see the nut hole in this picture:

https://gist.github.com/gsilos/88107...4129411471.jpg

This is the nut positioned in the hole of the break arm.

https://gist.github.com/gsilos/88107...e%2520hole.jpg

silos

Thank you for this link! looks like very similar. I will try to communicate with the owner of this website and check if he can open one of these packages and compare with the pictures I have...

silos

Nice post! Excelent toughts about how to handle a nut !

Since this bike is brand new (I just received it at home, unboxed and started assembling everything) I also think that something was weird with this nut from the beginning... when I first used a tool on it I could see something was not the same as the other nuts. this one specifically was already slight larger than the others for the same allen key I was using to tight it.

So... since assembling bike is not something I do everyday , yes, you are right... there is a chance of me being the big cause of problem here... but I can tell you that due to the conditions I found this nut when I first touched it, that this chance is under 10%

dedhed

Well then I'd be talking to the people I bought it from about sending a replacement nut or brake arm.

silos

I think I finally found a workaround. And what leads me to workaround this? Lockdown! of course. Guys, I dont know your area, but here in Berlin, it is difficult to get parts to replacement nowadays. Today was last drop for me. I went to a hardware shop to try to look for some bolts and nuts. When I arrived in front of the door, security came to me and asked me what I was doing there. I just answered: I came here to find some bolts. He replied: You cannot shop.

Okay. That is enough. I returned home and decided to built the bolt myself with what I had in hands. And here is the result:


this is how the final product of all this effort leads me. I think this will last during all lockdown hahaha

this is how the rear break is with the original bolt installed.

this is how the bolt become after I create a hole in it.

this is all the hardware I use to fix the cable in the front brake.

I think that little adventure ends here. I appreciate all your help during this journey! Thank you all and see you in the next adventure! \o

Juan el Boricua

Great job, Silos. Are you sure it will last just until the restrictions are lifted!?!? If it were me, that'll be the end of it 'til it breaks again or the bike was sold!!!
Kudos to you for using a nylock nut, as it will not back itself up.