Stripped downtube boss

[rcnute]

My driveside downtube shifter boss is stripped. I would like to run downtube shifters on the bike. What's the best way to fix this? Thanks!

Ryan

[sales guy]

If you can, get a helicoil and use that. It depends on how thick the boss is and the type of boss. Also, some, they are a mechanical style like on some alloy frames and are replaceable.

it's an M5 x .80 tap/bolt size.

[zmudshark]

I have had some luck with similar repairs using Permatex/Loctite thread repair epoxy. It has also failed, so YMMV. A helicoil is a better bet.

[ultraman6970]

Hmm... jagwire has something called direct cable adjusters, the thing is this, I do not know if they will fit in the threaded hole, maybe somebody has one moving around and can check out the diameter???

http://jagwire.com/files/product/BSA035.jpg

[Peter P.]

Fill the hole with JB Weld, drill and tap a new hole.

I'd go that route if you can't get a Helicoil insert.

I'm assuming it's a steel boss.

[zmudshark]

Fill the hole with JB Weld, drill and tap a new hole.

I'd go that route if you can't get a Helicoil insert.

I'm assuming it's a steel boss.

I've tried that. JB doesn't cut that good a thread, in my amateur experience, and you need a special tap, or at least a broken one ground correctly. The expoxy I suggested above has a release agent for the bolt to preserve the thread, and when/if it works, it works. 50-50 IME

[Cicli]

Use a TimeSert. Far, far better than a helicoil. We use them on some very criticle parts. They dont fail when done correctly.

http://www.timesert.com

If its worth doing, its worth doing right.

[sales guy]

Hmm... jagwire has something called direct cable adjusters, the thing is this, I do not know if they will fit in the threaded hole, maybe somebody has one moving around and can check out the diameter???

http://jagwire.com/files/product/BSA035.jpg


These are for inside of cable stops or older STI levers. They go inside the housing stops on the shifts so you have an adjuster on internal routing frames. Like older Klein frames.

[Hindmost]

...or at least a broken one ground correctly...

Bottom tap.

[sales guy]

Use a TimeSert. Far, far better than a helicoil. We use them on some very criticle parts. They dont fail when done correctly.

http://www.timesert.com

If its worth doing, its worth doing right.


Never used these before. Do they have the tang inside for depth setting or no?

[zmudshark]

Bottom tap.Yes, that is the proper term.

[ftf]

Use a TimeSert. Far, far better than a helicoil. We use them on some very criticle parts. They dont fail when done correctly.

http://www.timesert.com

If its worth doing, its worth doing right.

+1 to the timeSert.

[EricEstlund]

For just about any threaded insert you need to drill and tap to the insert size, which steps you back to the M5. While that could certainly work, you might find it easier to just tap the old M5 to 12-28.