Page 2 of 2 FirstFirst 12
Results 11 to 19 of 19

Thread: 77 GS750B Front Caliber - What make/model will swap?

  1. #11
    Join Date
    Nov 2018
    Location
    Mundy Twp, Michigan
    Posts
    467

    Default

    Quote Originally Posted by Grimly View Post
    Believe me, the early hockey-puck calipers are utter rubbish compared to even the ones that came immediately after. That was my experience with two of them on the 79 850, and I was glad to discover the later calipers fitted straight on as a factory upgrade, if you like. Even the later ones aren't perfect, and they're out-performed by much more recent calipers and discs, as Dan suggests. However, as a cheap and effective upgrade, if you can get a low-mileage caliper from an 80-onwards bike, you'd notice the improvement.
    Thanks for the input. So the 82 GS650G should fit and be an upgrade in braking?
    - 1983 GS850L ~ 30,000 miles and going up - Finally ready for a proper road trip!
    - 1981 GS850G ~ 44,000 miles, resto-mod project
    - 1977 GS750B ~ Restoration Project
    - 1977 GS750B ~ Parts

  2. #12
    Join Date
    Sep 2012
    Location
    Ireland
    Posts
    4,697

    Default

    Quote Originally Posted by 93Bandit View Post
    Thanks for the input. So the 82 GS650G should fit and be an upgrade in braking?
    If the mount is the same and the diam / offset of the disc is the same, I think it will fit.
    ---- Dave
    79 GS850N - Might be a trike soon.
    80 GS850T Single HIF38 S.U. SH775, Tow bar, Pantera II. Gnarly workhorse & daily driver.
    79 XS650SE - Pragmatic Ratter - goes better than a manky old twin should.
    92 XJ900F - Fairly Stock, for now.

    Only a dog knows why a motorcyclist sticks his head out of a car window

  3. #13
    Burque73's Avatar
    Burque73 is offline Forum Sage Past Site Supporter
    Super Site Supporter
    Join Date
    Mar 2016
    Location
    Albuquerque, NM
    Posts
    4,268

    Default

    Quote Originally Posted by 93Bandit View Post
    My end goal is a fun bike to ride around town. It will see zero track time and I don't ride hard at all. So factory performance is sufficient.

    @Burque73 is selling front calipers off a 1982 GS650G. Can't tell from the parts list image if they will fit or not. Does anyone know if they will?

    As for brake lines, I will be using Earls parts and building new ones.
    I didn't list it, but I also have the front wheel with both rotors from that 650G. My thought was to hang onto an extra set of rotors to eventually swap them over onto the 850. Honestly, I'd much rather them help someone get back on the road than sit in a "maybe use eventually" pile here.

    Let me know if I can help.
    Roger

    Current rides
    1983 GS 850G
    2003 FJR 1300A
    Gone but not forgotten 1985 Rebel 250, 1991 XT225, 2004 KLR650, 1981 GS850G, 1982 GS1100GL, 2002 DL1000, 2005 KLR650, 2003 KLX400

  4. #14
    Join Date
    Nov 2018
    Location
    Mundy Twp, Michigan
    Posts
    467

    Default

    Quote Originally Posted by salty_monk View Post
    The G caliper should fit your bike, you may have to change to the 550E/1000C rotor worst case. I believe all the calipers will interchange except for L models.
    Pulled the wheel off and double checked rotor diameter. It's the 296mm.

    Quote Originally Posted by Grimly View Post
    If the mount is the same and the diam / offset of the disc is the same, I think it will fit.
    Unsure about those measurements and I don't know if I can get them.

    Quote Originally Posted by Burque73 View Post
    I didn't list it, but I also have the front wheel with both rotors from that 650G. My thought was to hang onto an extra set of rotors to eventually swap them over onto the 850. Honestly, I'd much rather them help someone get back on the road than sit in a "maybe use eventually" pile here.

    Let me know if I can help.
    Thanks for chiming in Burque. I'm interested in at least one front caliber if it will fit my 750. Could you measure center to center of the mount holes on the fork leg to compare to mine? If that dimension is the same, maybe we can work something out. Also, are the caliper pistons free or are the stuck in need of rebuilding?

    On a side note, I was really hoping to have this bike road ready come spring, but it seems like every where I turn there's something else that needs to be fixed. Joys of working on older machines! My wife and I are expecting our 2nd child end of April, so after that I won't have any garage time for a while so I really want to get this thing going before that, budget permitting. Fingers crossed!

    As always, all the help from everyone is greatly appreciated!
    - 1983 GS850L ~ 30,000 miles and going up - Finally ready for a proper road trip!
    - 1981 GS850G ~ 44,000 miles, resto-mod project
    - 1977 GS750B ~ Restoration Project
    - 1977 GS750B ~ Parts

  5. #15
    Burque73's Avatar
    Burque73 is offline Forum Sage Past Site Supporter
    Super Site Supporter
    Join Date
    Mar 2016
    Location
    Albuquerque, NM
    Posts
    4,268

    Default

    Quote Originally Posted by 93Bandit View Post
    Pulled the wheel off and double checked rotor diameter. It's the 296mm.



    Unsure about those measurements and I don't know if I can get them.



    Thanks for chiming in Burque. I'm interested in at least one front caliber if it will fit my 750. Could you measure center to center of the mount holes on the fork leg to compare to mine? If that dimension is the same, maybe we can work something out. Also, are the caliper pistons free or are the stuck in need of rebuilding?

    On a side note, I was really hoping to have this bike road ready come spring, but it seems like every where I turn there's something else that needs to be fixed. Joys of working on older machines! My wife and I are expecting our 2nd child end of April, so after that I won't have any garage time for a while so I really want to get this thing going before that, budget permitting. Fingers crossed!

    As always, all the help from everyone is greatly appreciated!

    The mounting holes are 72.43mm or 2-27/32" center to center, give or take a hair.

    Since the calipers are already off of the forks I struggled to get the bolts (axles?) out to separate it and check the piston. It got late and it's cold in the garage too. I may try a bit of compressed air to move the piston tomorrow. The climate here and in Colorado where this bike lived is pretty dry, plus all of the fluids I drained from this 650 were the appropriate colors so the PO took care of maintenance it seems.

    What if you took both calipers, the fork legs, rotors and scrounged up a spoke wheel that you could put another rotor on. That'd be a sweet upgrade. Sounds too easy though. The upper fork tubes are 35mm. Would they even fit a 750? These are 31-3/16 long from the top to center of the axle.
    Roger

    Current rides
    1983 GS 850G
    2003 FJR 1300A
    Gone but not forgotten 1985 Rebel 250, 1991 XT225, 2004 KLR650, 1981 GS850G, 1982 GS1100GL, 2002 DL1000, 2005 KLR650, 2003 KLX400

  6. #16
    Join Date
    Nov 2018
    Location
    Mundy Twp, Michigan
    Posts
    467

    Default

    Quote Originally Posted by Burque73 View Post
    The mounting holes are 72.43mm or 2-27/32" center to center, give or take a hair.

    Since the calipers are already off of the forks I struggled to get the bolts (axles?) out to separate it and check the piston. It got late and it's cold in the garage too. I may try a bit of compressed air to move the piston tomorrow. The climate here and in Colorado where this bike lived is pretty dry, plus all of the fluids I drained from this 650 were the appropriate colors so the PO took care of maintenance it seems.

    What if you took both calipers, the fork legs, rotors and scrounged up a spoke wheel that you could put another rotor on. That'd be a sweet upgrade. Sounds too easy though. The upper fork tubes are 35mm. Would they even fit a 750? These are 31-3/16 long from the top to center of the axle.
    I set my dial caliper to 72.4 and held it up to the mount holes on the fork leg. Looks like that dimension is the same so the caliber should mount. Whether or not it's the correct offset or not, I don't know.

    I measured my fork tubes and they are 35mm and ~31" long as well, so they would likely fit a 750. However, that's a bit more involved than I wanted to get right now, not to mention I wouldn't be able to afford the shipping costs on all that.

    As for piston movement, don't worry about it. Wouldn't hurt to rebuild it anyways probably. I'll PM you.
    - 1983 GS850L ~ 30,000 miles and going up - Finally ready for a proper road trip!
    - 1981 GS850G ~ 44,000 miles, resto-mod project
    - 1977 GS750B ~ Restoration Project
    - 1977 GS750B ~ Parts

  7. #17
    Join Date
    Sep 2012
    Location
    Ireland
    Posts
    4,697

    Default

    Only thing I found as a gotcha was the L model forks have a different caliper mounting bracket, because of the axle position and the placement of the caliper on the disc as a direct result of that. However, the caliper is the same, so acquiring another pair of standard caliper mounts sorted that out.
    I'm not even sure the 750 35mm fork legs even had an L model to muddy the waters, anyway.
    ---- Dave
    79 GS850N - Might be a trike soon.
    80 GS850T Single HIF38 S.U. SH775, Tow bar, Pantera II. Gnarly workhorse & daily driver.
    79 XS650SE - Pragmatic Ratter - goes better than a manky old twin should.
    92 XJ900F - Fairly Stock, for now.

    Only a dog knows why a motorcyclist sticks his head out of a car window

  8. #18
    Join Date
    Nov 2018
    Location
    Mundy Twp, Michigan
    Posts
    467

    Default

    Quote Originally Posted by Grimly View Post
    Only thing I found as a gotcha was the L model forks have a different caliper mounting bracket, because of the axle position and the placement of the caliper on the disc as a direct result of that. However, the caliper is the same, so acquiring another pair of standard caliper mounts sorted that out.
    I'm not even sure the 750 35mm fork legs even had an L model to muddy the waters, anyway.
    That would make sense, the differences between G and L due to L axle placement.


    Roger is sending me all 3 calipers from the 650G. I will be sure to update the thread once they arrive and are installed.

    Thank you again to all those who helped out!
    - 1983 GS850L ~ 30,000 miles and going up - Finally ready for a proper road trip!
    - 1981 GS850G ~ 44,000 miles, resto-mod project
    - 1977 GS750B ~ Restoration Project
    - 1977 GS750B ~ Parts

  9. #19
    Join Date
    Nov 2018
    Location
    Mundy Twp, Michigan
    Posts
    467

    Default

    The calipers Roger sent me arrived today. I'm under the weather so won't be able to check fitment for at least a few days, but I'll update as soon as I get the chance.
    - 1983 GS850L ~ 30,000 miles and going up - Finally ready for a proper road trip!
    - 1981 GS850G ~ 44,000 miles, resto-mod project
    - 1977 GS750B ~ Restoration Project
    - 1977 GS750B ~ Parts

Posting Permissions

  • You may not post new threads
  • You may not post replies
  • You may not post attachments
  • You may not edit your posts
  •