Author Topic: Caliper  (Read 2099 times)

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Offline bwaller

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Caliper
« on: October 28, 2017, 04:10:00 PM »
Looking for an underslung, opposed piston rear caliper. Must be something available/used during the 70's maybe 80's.

Any suggestions?

Offline slikwilli420

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Re: Caliper
« Reply #1 on: October 28, 2017, 05:33:40 PM »
You can still find the grimeca ones used on the rear. See them on vintage flat track bikes. Not appreciably lighter than a front though. Not much else period comes to mind. If you can go more modern use a Brembo p32 off a Ducati monster. Light, readily available and cheap.  That's what I'm going to use.
All you gotta do is do what you gotta do.

Vintage Speed Parts Mashup: http://forums.sohc4.net/index.php?topic=133638.0
Rickman CR Parts Kit Refresh: http://forums.sohc4.net/index.php/topic,154837.0.html
AHRMA CB750 Racer: http://forums.sohc4.net/index.php/topic,158461.0.html
AHRMA Superbike Heavyweight Racer: http://forums.sohc4.net/index.php/topic,173120.0.html
'76F CB750 Patina Redemption: http://forums.sohc4.net/index.php/topic,174871.0.html

Offline 754

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Re: Caliper
« Reply #2 on: October 28, 2017, 06:37:21 PM »
The PM small caliper used in the 80,s weighs like 14 oz,  not sure if that would be enough braking they are far smaller than the Grimeca.
« Last Edit: October 28, 2017, 06:41:32 PM by 754 »
Maker of the WELDLESS 750 Frame Kit
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Kelowna B.C.       Canada

My next bike will be a ..ANFOB.....

It's All part of the ADVENTURE...

73 836cc.. Green, had it for 3 decades!!
Lost quite a few CB 750's along the way

Offline Tintop

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Re: Caliper
« Reply #3 on: October 29, 2017, 06:58:17 AM »
You can still find the grimeca ones used on the rear. See them on vintage flat track bikes. Not appreciably lighter than a front though. Not much else period comes to mind. If you can go more modern use a Brembo p32 off a Ducati monster. Light, readily available and cheap.  That's what I'm going to use.

Be careful using the Grimeca, they have been out of production for a while and rebuild kits are very hard to find. 
1977 CB550/4 Cafe - Speed Warrior / BOTM 03/11
1980 CB750F (project)
Whittaker GBF Vintage Racing Sidecar (XS750 power) - ITG / 151's / CMR Racing Products (SOLD)
1976 CB400 SS - stock / BOTM 04/11 (SOLD)
1973 CB750 K - basket case (SOLD)
77 CB550 Cafe build
550/750 Filter Thread
Sidecar Rebuild Thread

Offline slikwilli420

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Re: Caliper
« Reply #4 on: October 29, 2017, 09:18:44 AM »
I've heard that, which is a bummer. If I cannot find a kit for my front when it needs it I'll upgrade to an AP unit. Doesn't give Brent many options to stay period.
All you gotta do is do what you gotta do.

Vintage Speed Parts Mashup: http://forums.sohc4.net/index.php?topic=133638.0
Rickman CR Parts Kit Refresh: http://forums.sohc4.net/index.php/topic,154837.0.html
AHRMA CB750 Racer: http://forums.sohc4.net/index.php/topic,158461.0.html
AHRMA Superbike Heavyweight Racer: http://forums.sohc4.net/index.php/topic,173120.0.html
'76F CB750 Patina Redemption: http://forums.sohc4.net/index.php/topic,174871.0.html


Offline Medyo Bastos

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Re: Caliper
« Reply #6 on: October 29, 2017, 11:56:46 AM »
You looking for front or rear? I have a few wrapped up under the bed


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Offline Tintop

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Re: Caliper
« Reply #7 on: October 29, 2017, 06:50:41 PM »
I've heard that, which is a bummer. If I cannot find a kit for my front when it needs it I'll upgrade to an AP unit. Doesn't give Brent many options to stay period.

To do the last ones I used some Brembo seals, ebay pistons, and it took a couple of attempts to find a piston seal.  The Brembo is to thin.  Not saying they can't be rebuilt, just not off the shelf, next day parts availability.
1977 CB550/4 Cafe - Speed Warrior / BOTM 03/11
1980 CB750F (project)
Whittaker GBF Vintage Racing Sidecar (XS750 power) - ITG / 151's / CMR Racing Products (SOLD)
1976 CB400 SS - stock / BOTM 04/11 (SOLD)
1973 CB750 K - basket case (SOLD)
77 CB550 Cafe build
550/750 Filter Thread
Sidecar Rebuild Thread

Offline 754

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Re: Caliper
« Reply #8 on: October 29, 2017, 08:00:56 PM »
Which Grimeca is hard to get kits for, the big caliper Or the smaller 41 mm type .
Maker of the WELDLESS 750 Frame Kit
dodogas99@gmail.com
Kelowna B.C.       Canada

My next bike will be a ..ANFOB.....

It's All part of the ADVENTURE...

73 836cc.. Green, had it for 3 decades!!
Lost quite a few CB 750's along the way

Offline Terry in Australia

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I was feeling sorry for myself because I couldn't afford new bike boots, until I met a man with no legs.

So I said, "Hey mate, you haven't got any bike boots you don't need, do you?"

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Offline bwaller

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Re: Caliper
« Reply #10 on: October 30, 2017, 08:25:08 AM »
Thanks all.

That little Brembo should fit the bill and is lightweight. It probably uses the same pads I use on the front, parts & pads are easily available. I can always invert it after it's bled. I plan to talk to Mr. Morse about a proper sized master cyl.

Offline 754

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Re: Caliper
« Reply #11 on: November 05, 2017, 09:25:08 PM »
 Sandy Kosman is now making new AP knockoffs... without the name on them.
Brand new less pads 139.00 plus shipping.
 SK Racing Products 707 799 7639
Maker of the WELDLESS 750 Frame Kit
dodogas99@gmail.com
Kelowna B.C.       Canada

My next bike will be a ..ANFOB.....

It's All part of the ADVENTURE...

73 836cc.. Green, had it for 3 decades!!
Lost quite a few CB 750's along the way