Author Topic: stripped brake line fitting in caliper......Helicoil possible? (Read 18902 times)

sinister902 · « **on:** April 27, 2009, 05:31:25 PM »

as the title states.....I managed to strip the threads trying to bleed the front caliper cause the bleeder is snapped off from previous owner, and the threads stripped right out on me.....I have been trying to locate a cheap caliper, but if I cannot find one.....can I get away with a helicoil?

Markcb750 · « **Reply #1 on:** April 27, 2009, 05:36:22 PM »

I would check here

http://www.emhart.com/products/helicoil.asp

email/online tech support is available.

WHALEMAN · « **Reply #2 on:** April 27, 2009, 05:48:43 PM »

I am not sure this would work but an idea I had would be to buy a speedbleeder in a larger size and then use a blind tap to thread the hole. Dan

sangyo soichiro · « **Reply #3 on:** April 27, 2009, 05:49:17 PM »

I wonder if you could go to the next larger pipe thread and, if worse comes to worse, just use a plug instead of the nipple-type thing...

If you do this though, make sure you re-tap it with a tapered thread (NPT - National Pipe Taper).

http://www.engineeringtoolbox.com/npt-national-pipe-taper-threads-d_750.html

themotoworks · « **Reply #4 on:** April 27, 2009, 06:04:26 PM »

i think a helicoil would work, as long as the seal is good. i've fixed them before by drilling out the threaded hole, turning a piece of aluminum and press fitting it, then rethreading... worked well

cappy · « **Reply #5 on:** April 27, 2009, 06:08:22 PM »

I have had much success using TimeSerts. Look them up on the web.

Basically they are a thin wall sleeve that uses the same pitch of thread but oversized diameter (solid piece sleeve)

sinister902 · « **Reply #6 on:** April 27, 2009, 10:35:51 PM »

i must clarify, i stripped the threads for the brake line itself going into the caliper, not the bleeder.....the bleeder was snapped off by previous owner, so i was bleeding using the line, and stripped the threads out......and after looking at pictures of helicoils, i dont think they will work in this application. I need a CB550 caliper......

jaknight · « **Reply #7 on:** April 27, 2009, 10:46:49 PM »

Hey sin's sister,

You might try checking the SpeedBleeder site itself. I seem to recall that they had a procedure there for fixing a stripped thread hole. I can't recall what the procedure was, but I am sure they at least at one time had a fix procedure there. See what they recommend.......

Just a thought, you never know.......

Edit AddOn.... Well, I guess SpeedBleeder has removed that section; I did a search there and couldn't find it

~ ~ ~ jaknight ~ ~ ~

bryanj · « **Reply #8 on:** April 27, 2009, 11:42:47 PM »

I wouldnt helicoil that thread, caliper from 350, 360,400 four, 500 four and twin and 550are all the same

WHALEMAN · « **Reply #9 on:** April 28, 2009, 02:12:17 AM »

Quote from: soichiro on April 27, 2009, 05:49:17 PM

I wonder if you could go to the next larger pipe thread and, if worse comes to worse, just use a plug instead of the nipple-type thing...

If you do this though, make sure you re-tap it with a tapered thread (NPT - National Pipe Taper).

http://www.engineeringtoolbox.com/npt-national-pipe-taper-threads-d_750.html

These threads are not pipe thread. Dan

Toxic · « **Reply #10 on:** April 28, 2009, 03:47:46 AM »

So if it doesn't work and the seal lets go while your riding you're in a world of trouble.

keep looking for a replacement caliper. They are out there.

Not a chance I would take.

jinshiyang · « **Reply #11 on:** June 15, 2009, 11:12:33 PM »

and after looking at pictures of helicoils, i dont think they will work in this application.http://www.xhcljx.com/eng

754 · « **Reply #12 on:** June 16, 2009, 07:49:30 AM »

This wont look stock, but you can tap it to a metric banjo size or NPT, then install an adaptor to braided line & be back in business.

bikebitzofvt · « **Reply #13 on:** June 16, 2009, 09:25:26 AM »

I recall seeing a stainless insert to repair damaged bleeders. I think it was in a H-D aftermarket supplier's catalog. It looked nicer than this:

http://www.truechoice.com/prodinfo.asp?number=BLEEDER+KIT

But, this should fix your problem...

Good luck!

MRieck · « **Reply #14 on:** June 16, 2009, 10:29:36 AM »

Quote from: bryanj on April 27, 2009, 11:42:47 PM

I wouldnt helicoil that thread, caliper from 350, 360,400 four, 500 four and twin and 550are all the same

I have to agree with Bryan...there are so many used calipers out there it isn't worth the time to try and repair it (which very well might not work in the end anyway.) Plus you said the bleeder was screwed up too.

sinister902 · « **Reply #15 on:** June 17, 2009, 10:45:55 AM »

I did in fact find a replacement caliper for $40, and went that route. Thanks for the help guys!

MRieck · « **Reply #16 on:** June 17, 2009, 11:07:13 AM »

Quote from: sinister902 on June 17, 2009, 10:45:55 AM

I did in fact find a replacement caliper for $40, and went that route. Thanks for the help guys!

You did the right thing.

Raul CB750K1 · « **Reply #17 on:** June 18, 2009, 12:43:30 PM »

My .02 in this issue.

I had handlebar switches installed in my Sanglas bike. When I fitted the mirrors I found out that what seemed to be good thread were indeed ruined- the mirror locknut will snap with the slightest torque.

So I found myself in your same dichotomy: buy new switches or helicoil. Sure, there are plenty of switches out there but I would have to remove the handlebar and reroute the wires, while helicoil is just a matter of five minutes.

I could buy used switches and find out that the threads were bad too, and after all, didn't we enjoy these challenges? replacing is the easy thing to do, restoring and repairing is what it all about.

Contrary to the opinions here, I think a helicoils would work perfectly on the banjo bolt of the brake caliper. Why? because the sealing is done at the crush washer, and even when you need to drill to a bigger size, it is not that big of a difference. And even if it is, you can always use a bigger washer of the same diameter (10mm), as you don't replace that banjo bolt often.

So you opted for replacing. Guess what did I opt for... :-)

754 · « **Reply #18 on:** June 18, 2009, 05:07:31 PM »

Raul.. BIG difference between a through hole,
and a Shallow hole with a seat (that is CRUCIAL) for sealing..

Raul CB750K1 · « **Reply #19 on:** June 19, 2009, 07:24:00 AM »

Quote from: 754 on June 18, 2009, 05:07:31 PM

Raul.. BIG difference between a through hole,
and a Shallow hole with a seat (that is CRUCIAL) for sealing..

From what I understand, it was not the bleed nipple what was stripped, but the hole for the banjo bolt for the brake line. There the sealing is made at the washer if I'm not wrong.

Even if it was the bleed nipple, as the sealing is done at the seat, much better. You only need to drill carefully and insert a short Helicoil, as it has proven stronger than aluminum threads, to guarantee you will have a strong seat of the nipple against the seat.

Not trying to beat a dead horse, but I really think there is nothing wrong in repairing a brake caliper -as long as you can easily find Helilcoil of such a fine thread-

MRieck · « **Reply #20 on:** June 19, 2009, 07:32:45 AM »

Quote from: Raul CB750K1 on June 18, 2009, 12:43:30 PM

My .02 in this issue.

I had handlebar switches installed in my Sanglas bike. When I fitted the mirrors I found out that what seemed to be good thread were indeed ruined- the mirror locknut will snap with the slightest torque.

So I found myself in your same dichotomy: buy new switches or helicoil. Sure, there are plenty of switches out there but I would have to remove the handlebar and reroute the wires, while helicoil is just a matter of five minutes.

I could buy used switches and find out that the threads were bad too, and after all, didn't we enjoy these challenges? replacing is the easy thing to do, restoring and repairing is what it all about.

Contrary to the opinions here, I think a helicoils would work perfectly on the banjo bolt of the brake caliper. Why? because the sealing is done at the crush washer, and even when you need to drill to a bigger size, it is not that big of a difference. And even if it is, you can always use a bigger washer of the same diameter (10mm), as you don't replace that banjo bolt often.

So you opted for replacing. Guess what did I opt for... :-)

Nice to see apost from you Raul....where have you been? If the bleeder is that messed up I would question the condition of the tapered sealing surface. I'd guess it is galled and in poor shape. Another thing is the cost of a helicoil set (insert tool, tap and inserts)......they are not cheap and if a shop did the job it would cost the same as a replacement. I like Helicoils and use them all the time on heads but there is an initial investment involved.

MRieck · « **Reply #21 on:** June 19, 2009, 07:36:52 AM »

Quote from: 754 on June 18, 2009, 05:07:31 PM

Raul.. BIG difference between a through hole,
and a Shallow hole with a seat (that is CRUCIAL) for sealing..

As an aside, a standard tapered Helicoil tap will not work with a shallow hole. You need to purchase an STI bottoming tap.....more cost

754 · « **Reply #22 on:** June 19, 2009, 07:38:39 AM »

Helicoils dont work well in shallow holes.

The PO stripped his brakeline threads (steel line) in a 550 caliper.

He could tap to the bigger banjo thread by removing the seat & probably drilling right thru.

But helicoiling, stock fitting to cone threads, not enough room.

Even if you ground a second tap, to more of a bottoming style, you still lose a bit of room as the end of coil must have full thread (when installed). If you ever ran a helicoil too shallow & had the lower part of thread undersize, you will know what I mean.

MRieck · « **Reply #23 on:** June 19, 2009, 07:46:45 AM »

Quote from: 754 on June 19, 2009, 07:38:39 AM

Helicoils dont work well in shallow holes.

The PO stripped his brakeline threads (steel line) in a 550 caliper.

He could tap to the bigger banjo thread by removing the seat & probably drilling right thru.

But helicoiling, stock fitting to cone threads, not enough room.

Even if you ground a second tap, to more of a bottoming style, you still lose a bit of room as the end of coil must have full thread (when installed). If you ever ran a helicoil too shallow & had the lower part of thread undersize, you will know what I mean.

I know what you mean. The bottoming taps I use only lose about 1 thread (if that). Helicoils have their limits but I've found you can use them just about all the time.

754 · « **Reply #24 on:** June 19, 2009, 07:47:59 AM »

A few words on repairing stripped bleeders. After you get it out IF there is any meat left in the seat area..

Sometimes you can go to a bigger bleeder, the trick though is to fixture up, and after oversize drilling the thread hole, touch up the seat. This requires a 90 deg included angle c-sink (available from KBC)

If the seat is gone , there is one more option that works on some calipers. Accel used to make a replacement seat&bleeder, The drill correct size to tap to 7/16 thread, tap & install. Use sealant to seal in insert, or dont cut thread right thru, that allows it to jam on the last tapered threads..

I have saved a few calipers..

754 · « **Reply #25 on:** June 19, 2009, 07:53:48 AM »

Mike you can get it to within 2 or 3 pitches from the bottom (in this case, you can pull the cone).

But you need the correct length, if any sticks out the top, it can be trouble, if you are not real careful trimming the top of coil, may lift and peel the thread.. it can be done, but some folks being in a rush, might not pull it off successfully.

Raul CB750K1 · « **Reply #26 on:** June 19, 2009, 09:00:05 AM »

I understand what you mean. The tap, in their first threads, are not the right diameter as it is designed to self-center. So if the hole is too shallow, when the tap bottoms out only a fraction of the hole has been threaded to accomodate the helicoil insert. That makes sense.

Regarding the initial investment of the tool vs replacement, if you think exclusively in economic terms and opportunity cost, you will always buy a replacement. But following that way of thinking, who would spend in a restoration the same -if not more- than in buying a new bike?

I like to think of it in a more philosophical way: I install my switches and find out I have an stumbling block with the mirror hole. I can always go to a bigger size, or buy different mirrors that can be tightened with a nut in the opposite side. All of them will solve the "problem" of how to fix mirrors on a bike, a problem that is completely unrelated with using the original ones, nor the original mount. You can always buy aftermarket mirrors with handlebar clamps.

When I stumbled onto that problem, all options considered, I thought that the most profitable was the repair. It may cost more in the short term -money- but I will surely learn something in the process, will have another tool in case I need it, and to my point of view, would be the option that not only would solve the problem, but would let me keep the original appearance.

I had the very same problem with a caliper in my Sanglas bike. I tried to fix it -in that case it was a broken bleed nipple that refused to get out-. Tried to drill it out, tried to tap a bigger hole with an oversize nipple, tried to fill the hole with epoxi and re-thread - no way, only a replacement did.

But hey, I tried....

IHWillys · « **Reply #27 on:** June 19, 2009, 10:51:38 AM »

Quote from: 754 on June 19, 2009, 07:38:39 AM

...
The PO stripped his brakeline threads (steel line) in a 550 caliper.

He could tap to the bigger banjo thread by removing the seat & probably drilling right thru....

Yes, this is a case of stripped threads in an inverted flare fitting, very difficult to repair and keep the inverted flare cone undamaged.

If the caliper was drilled/tapped for a banjo fitting, there would still be no sealing surface for the caliper side of the banjo so one would have to be machined on.

Recommended *repair* would've been to drill/tap the caliper to accept a flare fitting adapter. 1/8" NPT / -3AN(or whatever flare is desired) adapter would then screw into caliper and a brake line would attach to the adapter via a flare fitting.

Best course of action on such a plentiful part... just what sinister902 did, replace it. But don't trash the caliper, they may not be so plentiful someday.

Ken

jinshiyang · « **Reply #28 on:** June 30, 2009, 08:05:20 PM »

If the caliper was drilled/tapped for a banjo fitting, there would still be no sealing surface for the caliper side of the banjo so one would have to be machined on.thread insert helicoil

754 · « **Reply #29 on:** June 30, 2009, 08:18:06 PM »

There is a flat there.
I would do it like this, in drill or mill.

Line up existing hole, and clamp caliper

Drill to tap size

Mill flat seat with end mill

Countersink

Clamp cetering point in drillchuck, & use to guide tap straight.

Tap is Banjo thread size.

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Author Topic: stripped brake line fitting in caliper......Helicoil possible? (Read 18902 times)

Markcb750

WHALEMAN

WHALEMAN

jinshiyang

jinshiyang