Add disc tabs to steel F/F

[johnniecakes]

I have Colorado frame and fork hanging in the garage that I am deciding what to do with. One thought is to add tabs for disc brakes to both the frame and fork. Is it possible?

Thanks for any suggestions

[jtakeda]

Yes it’s possible but might be expensive and it will require a repaint

[R3awak3n]

some fork blades are not going to be beefy enough for discs so check that. Unless you go carbon disc fork and add tab in the back.

I would not do this, seems like too much money and hassle.

[David Kirk]

Is it possible? Yes. Should you do that? No.

In the rear one could add an ISO mount on the seat stay, re-space the rear to 135mm, and add a brace between the seat and chain stay to spread the load is it would probably be OK. Probably.

The fork is a different story. The fork blades we used on those bikes were fairly light and the material was pretty soft. It worked fine obviously for it's intended purpose....but....if you stick a disc brake to one of the fork blades I'd be shocked if it didn't fail. Hard braking will most likely un-rake (bend) the blade at a minimum or it will just full-on fail.

The material we use on steel bikes now is so much more advanced than the stuff that was used back in the day. There's a common misconception that "steel is steel" and that steel builders use the same stuff we did in the 70's, 80's, 90's and that is way off base. I wouldn't dream of making a bike out of that stuff now. Modern tubes are much lighter and much stronger at the same time....a win-win for sure. A good builder can make you a safe and fun steel disc fork today but they would never use a blade from the 1990's.

Sorry to rain on your idea.

dave

[johnniecakes]

Is it possible? Yes. Should you do that? No.

In the rear one could add an ISO mount on the seat stay, re-space the rear to 135mm, and add a brace between the seat and chain stay to spread the load is it would probably be OK. Probably.

The fork is a different story. The fork blades we used on those bikes were fairly light and the material was pretty soft. It worked fine obviously for it's intended purpose....but....if you stick a disc brake to one of the fork blades I'd be shocked if it didn't fail. Hard braking will most likely un-rake (bend) the blade at a minimum or it will just full-on fail.

The material we use on steel bikes now is so much more advanced than the stuff that was used back in the day. There's a common misconception that "steel is steel" and that steel builders use the same stuff we did in the 70's, 80's, 90's and that is way off base. I wouldn't dream of making a bike out of that stuff now. Modern tubes are much lighter and much stronger at the same time....a win-win for sure. A good builder can make you a safe and fun steel disc fork today but they would never use a blade from the 1990's.

Sorry to rain on your idea.

dave
Dave
Thanks for the thoughtful reply. I did not know the new steels were so different than the previous generations. I will probably just refinish it and run an Ultegra group with rim brakes

[David Kirk]

Dave
Thanks for the thoughtful reply. I did not know the new steels were so different than the previous generations. I will probably just refinish it and run an Ultegra group with rim brakes

that sounds like a good plan - enjoy the ride....they really are very good.

dave

[baldbones]

Dave
sorry to hijack the thread
but would you recommend a thru axle or QR for that new fork
Thanks!
Rick

[David Kirk]

Dave
sorry to hijack the thread
but would you recommend a thru axle or QR for that new fork
Thanks!
Rick

Are you asking what type of drops do I think a steel disc brake fork should have? If so I think either can work fine. If I was going to use a QR I'd want the dropout slots to be angled in the proper direction so that braking forces don't try to slip the wheel out of the fork.

Strictly speaking a TA will be stiffer but much of it depends on the hub design. If the QR hub has a small diameter axle (not just the ends but all the way through) then it will be more flexible.....if the hub has a large diameter axle (that a TA could slip through) and has end caps that downsize it to 9mm at the ends the difference is stiffness will be little to none.

The real advantage a TA has in many cases is the fact that even if left loose it won't allow the wheel to come out.

Some will argue that a TA will position the wheel better so that rotor-to-caliper alignment will be better....I understand the premise. The thought being that with a QR set up that the axle doesn't have a single "home" and that there's play in it. At the risk of sounding like a jerk if your axle doesn't go to the same place each and every time your builder dropped the ball. I can promise you that a top shelf builder does not make a frame or fork that will have play in the dropout slots and this is not an issue if you choose a good builder.

Thanks for the question.

dave

[bitt3n]

At the risk of sounding like a jerk if your axle doesn't go to the same place each and every time your builder dropped the ball. I can promise you that a top shelf builder does not make a frame or fork that will have play in the dropout slots and this is not an issue if you choose a good builder.

If that's the case, both Seven and Enve are about to get angry phone calls about the slapdash methods of their respective fly-by-night operations, and I'm calling collect and speaking real slow just to rack up the long-distance charges.

[baldbones]

Dave
As ever a great reply
Thanks for taking the time to answer
Rick

[R3awak3n]

If that's the case, both Seven and Enve are about to get angry phone calls about the slapdash methods of their respective fly-by-night operations, and I'm calling collect and speaking real slow just to rack up the long-distance charges.

ahahh yeah.

My elephant, everytime I clamped the front I would have to do minor adjustments to stop some rub. Not a big deal. My rawland was the same thing. Interestingly enough it was always in the front, back was always ok

[bitt3n]

ahahh yeah.

My elephant, everytime I clamped the front I would have to do minor adjustments to stop some rub. Not a big deal. My rawland was the same thing. Interestingly enough it was always in the front, back was always ok

Just out of curiosity, do you also use the folded business card method to center it? Eyeballing it seems impossible.

[R3awak3n]

Just out of curiosity, do you also use the folded business card method to center it? Eyeballing it seems impossible.

yes, I actually got some of these

https://ae01.alicdn.com/kf/HTB1IGp5JpXXXXXnXFXXq6xXFXXXO/TB-BR10-Brake-caliper-alignment-tool-for-tunning-MTB-bike-Disc-Brake-gap-Birzman-Clam-Disc.jpg_640x640.jpg

worked great on the elephant and now works great on my open (which I never have problems when the brakes are centered and using TA but to initially set it up or when I change up wheelset.