Author Topic: Cb750 caliper insert removal (got out, but ruined) (Read 1742 times)

Davez134 · « **on:** February 13, 2015, 03:35:13 PM »

I finally got my front caliper that has been holding my project up, and this insert is in the wrong side. Been searching for removal method with no luck. How do I get this out without ruining it? If I have to find another one I'm gonna lose it!

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Davez134 · « **Reply #1 on:** February 13, 2015, 03:42:34 PM »

Don't know why this posted so many times! Sorry

rb550four · « **Reply #2 on:** February 13, 2015, 04:10:18 PM »

I'm not a 750 guy by any means ,but, doesn't the flanged brake line go in that hole and mate with the surface that you would like to remove?
And , I haven't had to do this but , if you go on the extra posts that you've made, can't you remove them by hitting remove one post at a time?

Davez134 · « **Reply #3 on:** February 13, 2015, 04:14:26 PM »

Quote from: rb550four on February 13, 2015, 04:10:18 PM

I'm not a 750 guy by any means ,but, doesn't the flanged brake line go in that hole and mate with the surface that you would like to remove?

yes it does, but it needs to be in the hole to the rear, not the front. On my '72 the caliper goes on left side of the bike and hard line screws into the rear. The way this caliper is, the bleeder screw was in the rear hole.

rb550four · « **Reply #4 on:** February 13, 2015, 04:16:07 PM »

Would an easy-out allow you to unscrew it, providing that it was screwed in.

Davez134 · « **Reply #5 on:** February 13, 2015, 04:21:52 PM »

it appears to be a pressed in part. I don't want to try screwing anything in there and possibly mangling that surface because looking at parts diagrams, it doesn't seem like I can just get that part. But if others have done it with success I'll sure try

Davez134 · « **Reply #6 on:** February 13, 2015, 04:40:49 PM »

Seems like it is rusted in there pretty bad. Tried pb blaster, heat, not budging. tried inserting a nail from inside and pulling out. Nothing. Finally tried easy-out, just deformed it. So now for another question, anyone know if this part is available? Or have any laying around? I've wasted so much time and money than should be necessary with this front caliper situation.

Don R · « **Reply #7 on:** February 13, 2015, 04:41:55 PM »

The article that shows moving it for a double disc says put a proper size nail through the hole from the inside, put the nail point end in a vise and pull. The head of the nail will catch the part and pull it out.

Don R · « **Reply #8 on:** February 13, 2015, 04:42:38 PM »

But I could be wrong.

Davez134 · « **Reply #9 on:** February 13, 2015, 04:44:33 PM »

Quote from: Don R on February 13, 2015, 04:41:55 PM

The article that shows moving it for a double disc says put a proper size nail through the hole from the inside, put the nail point end in a vise and pull. The head of the nail will catch the part and pull it out.

Yeah, I saw that method and tried, heated, tried again. let cool, tried again. thing wouldnt budge. So, I figured maybe I could make ot spin a little in there and in the process ruined it.

scottly · « **Reply #10 on:** February 13, 2015, 05:09:27 PM »

sounds like I'm too late.

oldhatt45 · « **Reply #11 on:** February 13, 2015, 05:16:53 PM »

Davez

Going along the lines of what Scottly just posted, if you have a Machine Screw that will fit in there, you might be able to put a nut on it with a washer against the caliper and literally screw it out by tightening the nut. Don't know if it would work, but...............

Or if worst comes to worst, just use a drill and drill it out. Doesn't look like it's stainless, so maybe if it's aluminum, if you drill enough out, you might be able to get an ice pick in between the remaining piece and wedge it out.

Just a couple of ideas that ran through my head.

Hope you get it out.

Charlie

Old Moe Toe · « **Reply #12 on:** February 13, 2015, 05:26:46 PM »

The nail from the inside worked a treat for me.
Once I had the nail poking through I held the nail in a metal vice and then gently tapped the caliper with a softish hammer.
Was even able to put the offending item in the correct hole and re-use it.

Davez134 · « **Reply #13 on:** February 13, 2015, 05:36:49 PM »

Thanks for all the replies guys, I guess I was not clear with my last response. I got it out, ended up using all those methods and only one that worked was the screw. It was stuck in there so bad that I ruined the surface while pulling it out. I was trying to remove and still be able to reuse. I got it out but it is not useable now. I posted in the "parts wanted" section looking for a new one, as I don't see them for sale anywhere.

Old Moe Toe · « **Reply #14 on:** February 13, 2015, 06:02:07 PM »

I seem to remember on one of those twin disc set up threads that one bloke actually made one from a bit of brass. I think he used a drill press and a file once the central hole was drilled. It looked like a mighty fine job. No doubt it would take a bit of care and patience but it may be quicker than tying to find one.
Good luck.
BTW, enjoying reading your build in the project section.

scottly · « **Reply #15 on:** February 13, 2015, 06:12:02 PM »

Did you mess up the hole in the caliper, or just the insert? Post a pic of the insert.

Davez134 · « **Reply #16 on:** February 13, 2015, 06:46:04 PM »

Quote from: scottly on February 13, 2015, 06:12:02 PM

Did you mess up the hole in the caliper, or just the insert? Post a pic of the insert.

Caliper hole is fine. Insert is deformed, won't seat against hard line

Also before I waste 1 more minute of my life with this thing, I noticed that it has been crammed into a vise and the surface that mates with mounting bracket and bottom of caliper is slightly deformed. How important is it for these to be completely true. Hard to see in pictures but there is a small amount of deformity... Toast? Or still useable?

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754 · « **Reply #17 on:** February 13, 2015, 07:24:45 PM »

The Earls braided line adaptors do not need that in there, and seal just fine..
Caliper may be ok if the piston bore is still round.

Davez134 · « **Reply #18 on:** February 13, 2015, 07:33:53 PM »

I have all the rest of original parts, including hard line and slingshot cycles braided hoses. Just want this one little piece!

but still not sure if this caliper is worth it after noticing it was smashed in a vise (see pics above)

RAFster122s · « **Reply #19 on:** February 14, 2015, 04:57:37 AM »

You could take a file to the caliper body and carefully smooth the surface cutting back the area where the vise marks are and no one is going to notice. Like Frank has said, as long as the piston bore is not deformed it is still useable. The area where you pulled the seat for the brake line...can you post some pictures of the damage you feel you did there? Like someone else said, it can be drilled with a drill press a bit oversize and press fit with a brass insert threaded to fit the braided line. Or, threads cut in the body to a standard plumbing brass fitting that is threaded internally and externally. I believe Harrisluv does this to them.
- David

LesterPiglet · « **Reply #20 on:** February 14, 2015, 05:22:18 AM »

The vice marks on the body are nothing to worry about.

Davez134 · « **Reply #21 on:** February 14, 2015, 06:20:40 AM »

RAF122S, luckily I did no damage to caliper body when pulling seat. Only the seat got damaged. I already filed off the vise marks, wasn't worried too much about those, more worried that the front surface bowed out a bit from it. Bore still appears round though.

MCRider · « **Reply #22 on:** February 14, 2015, 06:33:37 AM »

Quote from: Davez134 on February 14, 2015, 06:20:40 AM

RAF122S, luckily I did no damage to caliper body when pulling seat. Only the seat got damaged. I already filed off the vise marks, wasn't worried too much about those, more worried that the front surface bowed out a bit from it. Bore still appears round though.

Are you committed to stock lines? If you go stainless braid, you'd have a banjo with a bolt running through it into the calipier. No need for the seat.

Davez134 · « **Reply #23 on:** February 14, 2015, 06:49:13 AM »

Yeah already committed to the stock line setup. Have all parts. This caliper was last bit. Been searching online for a solution, or a source for a similar seat that I can make work. Not much luck so far

mystic_1 · « **Reply #24 on:** February 14, 2015, 07:06:12 AM »

I've never seen a source of new replacements for that part. However it should be pretty simple for a competent machinist to reproduce one.

Having said that, are you sure yours cannot be massaged back into shape? It's not easy to tell from the picture you posted, but the critical areas on this part aren't very big. It does look to me as if the hole is been enlarged and may be off-center now, though, and the taper is the most sensitive portion.

Otherwise, source a junk caliper and cut the insert out rather than trying to pull it. That way you'll get the insert out with little risk of damage to the insert.

mystic_1

Davez134 · « **Reply #25 on:** February 14, 2015, 07:25:50 AM »

Yeah, I'm sure it's not useable. Posted in classifieds for junked caliper. Going to give this 1 more try then moving on.

MCRider · « **Reply #26 on:** February 14, 2015, 08:07:58 AM »

Quote from: mystic_1 on February 14, 2015, 07:06:12 AM

I've never seen a source of new replacements for that part. However it should be pretty simple for a competent machinist to reproduce one.

Having said that, are you sure yours cannot be massaged back into shape? It's not easy to tell from the picture you posted, but the critical areas on this part aren't very big. It does look to me as if the hole is been enlarged and may be off-center now, though, and the taper is the most sensitive portion.

Otherwise, source a junk caliper and cut the insert out rather than trying to pull it. That way you'll get the insert out with little risk of damage to the insert.

mystic_1

yEAH I would think that a bunged caliper should be easy to find on ebay or in a salvage yard. Our yard (cycle recycle Part II) has a box full of them. As many have mentioned they usually come out easy. I did the thread a wood screw in trick and as I was tightening it up it started to spin and pulled right out, no damage done. Threw it away sorry.

Davez134 · « **Reply #27 on:** February 14, 2015, 11:52:02 AM »

Yeah, I was hoping that the screw would cause it to spin but that little thing was in there good! Getting the word out to some friends locally here too, maybe I can find one soon.

strynboen · « **Reply #28 on:** February 14, 2015, 01:24:45 PM »

any maskinist can makt one..but ate or girling or any brake speilist must have this part..seen them in cars..too..

Davez134 · « **Reply #29 on:** February 15, 2015, 08:35:24 AM »

Fingers crossed...A friend says he has one in his garage, looking for me today. Almost too good to be true but hoping for the best!

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Author Topic: Cb750 caliper insert removal (got out, but ruined) (Read 1742 times)