Rear brake issue

[zachryan]

I have a 2004 st1300 and im in love with it but for the last few weeks.. i noticed the rear brake seems to be dragging a bit... I bled the system according to manual and it seemed fine and i was happy to have new fluid. Week goes by and i go out for a ride one day and i got about 2 kms from hime and pulled up to stop... Before even touching the brakes i could feel the bike slowing very quickly. I stoed and put on the center stand and could not move the rear wheel no matter what i did. Got the bike home and loosened the rear bleed screw and it freed up the wheel right away. Problem is now the slightest ressure on the rear brake abd it was clamp down hard enough to stop the bike in its tracks and will not release unrill i open a bleed screw.. help..

 

[Catmandu2]

Zach,,, you are about to be inundated with warnings to not ride your bike before doing a complete smc replacement. It is true,,, you should not ride it. I locked up my '04. And you are in the same dangerous situation. Stand by for further posts !! seriously,, CAt'

 

[zachryan]

I have no intention of riding it until it is fixed... I just dont know where to start ..

 

[Obo]

There's an SMC (secondary master cylinder) located on the drives side above the front brake. It activates the rear brake when the front brake is applied.

It's likely bad, most likely due to the brake fluid not being changed regularly.

While you can buy a rebuild kit, this often doesn't fix it as it's beyond the overhaul point.

This results in only one option: replacement.

We have a guru on the forum by the name of @Igofar.

He knows these bikes inside and out and is normally more than willing to help folks over the phone, email etc.

Since I've tagged him above I hope he'll chime in.

*also very glad to see you're not planning on riding it until fixed!

Cheers,

Obo.

 

[core-aggie]

I have no intention of riding it until it is fixed... I just dont know where to start ..

I'd start with reading the excellent tech articles in the "ST1300 Articles section, such as:

Article [13] - ST1300 Maintenance - Brakes- Avoiding the Pitfalls | ST1300 Articles

A close hands-on look at the Honda ST1300 braking system. These are personal observations about the things that can go wrong, why they go wrong and what can be done to keep things working sweetly. Updated April 2020 and to address more recent observations, to include information about the SMC...

www.st-owners.com

Article [13] - ST1300 Maintenance - Replacing the Secondary Master Cylinder (SMC) | ST1300 Articles

The usual format from me - Description, some useful photos and a few tips and tricks to help you to avoid the normal 'Doh!' moments - Like emptying all of the fluid out before realising that you wanted tomove the pistons out as far as possible; Like reftting everything before realising that you...

www.st-owners.com

 

[WhiskyW]

Some really good advice regarding the dreaded smc and brakes on the forum. Thanks for all the work and advice.