• Required reading for all forum users!!!

    Welcome!
    Register to access the full functionality of the GSResources forum. Until you register and activate your account you will not have full forum access, nor will you be able to post or reply to messages.

    A note to new registrants...
    All new forum registrations must be activated via email before you have full access to the forum.

    A Special Note about Email accounts!
    DO NOT SIGN UP USING hotmail, outlook, gmx, sbcglobal, att, bellsouth or email.com. They delete our forum signup emails.

    A note to old forum members...
    I receive numerous requests from people who can no longer log in because their accounts were deleted. As mentioned in the forum FAQ, user accounts are deleted if you haven't logged in for the past 6 months. If you can't log in, then create a new forum account. If you don't get an error message, then check your email account for an activation message. If you get a message stating that the email address is already in use, then your account still exists so follow the instructions in the forum FAQ for resetting your password.

    Have you forgotten your password or have a new email address? Then read the forum FAQ for details on how to reset it.

    Any email requests for "can't log in anymore" problems or "lost my password" problems will be deleted. Read the forum FAQ and follow the instructions there - that's what we have one for...

  • Returning Visitors

    If you are a returning visitor who never received your confirmation email, then odds are your email provider is blockinig emails from our server. The only thing that can be done to get around this is you will have to try creating another forum account using an email address from another domain.

    If you are a returning visitor to the forum and can't log in using your old forum name and password but used to be able to then chances are your account is deleted. Purges of the databases are done regularly. You will have to create a new forum account and you should be all set.

Brake piston issue, ordered from Bike Bandit???

1978GS750E

1978GS750E

Forum Sage
Super Site Supporter
Past Site Supporter
I ordered two sets of front brake pistons and seals for my 1978 GS750E thru Bike Bandit. I got one set and they cancelled the backorder??? Ordered another set and they shipped in 2 days! The problem lies in when I went to rebuild the calipers this morning. The pistons and seals that I received in both sets are 42mm diameter. The original pistons on my bike are 38mm diameter. I checked 3 websites, which I believe all use the same parts fiche, and part # 59100-45813 shows that it fits the front caliper for my bike. So.....can anyone verify what the correct diameter piston is in a 1978 GS750E? I want to make sure that someone has not changed the calipers on my bike before sending these pistons and seals back. I could just turn down the pistons but the seals are too big also. The end that holds the dust cover is the same on both the new and old pistons and the length is the same. Anyone have any ideas?
 
Alpha Sport shows these numbers...

Part# 59100-44823 Desc PISTON SET -SU USD Price 60.06 Quantity

*supersedes 59100-44820 59100-44821 59100-44822
 
Hi I looked around and I took this from Z1
Fits Front Brake Caliper - 38mm diameter Suzuki GV1200GLF/GLF2/GLG 1985-86 GS1100GZ/GD/GLZ/GLD 1982-83 GS1000GT/GLT/GX/GLX 1980-81 GS850GT/GX 1980-81 GS850GZ/GD 1982-83 GS850GLT/GLX/GLZ/GLD 1980-83 GS750ET/EX/EZ 1980-82 GS750ED/ESD 1983 GS750LT/LX 1980-81 GS700EF/ESF 1984 GV700GLF/GLF2 1985-86 GN400TX/TZ 1981-82 GN400...
i know it does not list 1978 gs750 but I cannot see the 750 be fitted with larger Pistons than the 1200, 1100 and 1000
I have not had a 750 so hopefully someone will be more helpfull

 
Thanks Hannibal! I have found a lot of confusion with these brakes. The bike that I have has the 38mm pistons and the "78" mounting bracket. The other bike that I sold had the larger pistons and the "77" mounting bracket, yet both were 1978 models and had dual disc brakes up front. It looks like Suzuki might have made a change mid-model year on these front brakes. Lots of the online parts sellers show the incorrect part numbers in their "where used" lists. It looks like I may have to actually talk to one of the "experts" at Bike Bandit, Partszilla, Z1, or Parts Outlaw to get the correct parts.

Geez......all I wanted was to stop a leaking caliper........boy this is fun! Oh well, at least it is cold here!
 
Is the bigger piston just for single disc setup. I think I can remember using a left caliper from my gs1000n on my son's gs550. The right caliper was from a twin setup and had a smaller piston.
 
I believe the larger piston is used in single brake bikes and the smaller 38mm piston is used in dual front brake bikes. none of the so-called "experts" at any of the online sellers can tell me the diameter of the pistons that they sell. May have to try the 38mm Honda pistons, at least they specify the diameter. Geez.....it's only 40 years old!
 
OK, now I'm at the end of the proverbial rope! Cannot find the Suzuki 38mm front brake pistons and seals anywhere. Or at least anyone that can verify that the pistons and seals that they sell are 38mm diameter. ANYONE know of a Suzuki brake piston and seal that is 38mm diameter and still available?
 
Upgrade to the twinpots if you don't care about originality. Part supply is still good on those...
 
59100-45833 is the part number for the 38mm pistons. I think I still have the kit. I'll take a pic tomorrow if I can find it.
 
That part number is not available on Parts Outlaw, and does not come up at all on Bike Bandit or Partzilla searches. Thanks anyway!
 
I'm looking for these myself right now. P/N for 78 piston set is 59100-44823

Unavailable on all the typical sites.

Can anyone recommend aftermarket 38mm pistons?
 
You must log in or register to reply here.

Similar threads

martin_montreal
braided steel brake line (front)
Replies
2
Views
100
1978GS750E
1978GS750E
T
Potential sale 1980 gs550L project + parts near Seattle, WA
Replies
0
Views
45
tadakan
T
S
Brakes, front tire, chain
Replies
13
Views
237
Shin-Ken 1074
Shin-Ken 1074
S
Wobble at low speeds
Replies
9
Views
230
first timer
first timer
E
'79 GS850 - One Year Ownership & Maintenance Summary
Replies
3
Views
71
emlivings
E
Back
Top