Secondary Master Cylinder Questions

Joined
Jan 6, 2010
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Lacombe, AB Canada
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05 ST1300
I've read a few threads here how the SMC can cause some problems on the ST1300. I've got an 05 non-ABS. The part of all this that bothers me the most is that these issues seem to be intermittent on some bikes and occur without warning and you wouldn't necessarily notice that there was a problem until it's too late. I took my SMC off the other day to try to see if there was any sign of problems. It all looked and operated really good; brakes released and there was no drag immediately upon release. But I couldn't find a way to peel back the rubber boot to inspect to see if there was corrosion behind it; at least not without risking damaging the boot. In fact it looked like it was sealed up really good and that there was no way moisture could get in. Any ideas on that conundrum; how to inspect without damaging?:confused:
Also - the newer SMC's have a slot for water drainage instead of a hole. Has anybody tried (successfully or unsuccessfully) to cut their own slot into their SMC to copy the factory's "new and improved" version? I don't see how there could be adverse effects from doing this - only positives - but then again, my vision's not always 20-20.
 
Joined
Jan 8, 2011
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Arizona
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2007 Honda ST1300A
You can pinch the boot between your thumb and first finger and gently start wiggling it then it will pop off. The two that I've inspected this week had green pond scum oooze out form behind it. I checked another members 09 and it was very clean, so I simply packed the rubber boot with SILICONE grease (scuba diving) in hopes that it will keep the rod water proofed and keep the moisture from seeping past the boot.
I did this to mine as well.
I think if we check it often and dry the area after we wash or ride in the rain, we should be ok.
I'll bet the ones that locked up were dirty, or neglected.
I inspect my SMC before EACH ride now!
don't want my wheel locking up in front of a buick.:D
 

dduelin

Tune my heart to sing Thy grace
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I think one would notice a brake dragging. These things are powerful but they are not that powerful. Let off the throttle and see if it coasts.....:confused: Of course if the brake locked up on application and did not release that might be a different story.

Just do the maintenance on time or interval and ride the thing. The SMC does not require any special attention beyond that.
 
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The weep hole was one change but the new ones also use different brake pads so there may be other changes. Parts fiche might show that. Cleaning behind the boot and a little silicone o-ring grease/dielectric grease, like chicken soup couldn't hoight.
 

Mellow

Joe
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The weep hole was one change but the new ones also use different brake pads so there may be other changes. Parts fiche might show that. Cleaning behind the boot and a little silicone o-ring grease/dielectric grease, like chicken soup couldn't hoight.
Yes, the front calipers are just a little larger, the pads are something like .5 inches longer... not sure if the internals of the caliper itself are different.
 
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Joe you've had both right? Do you notice any improvement in braking with the new design?
Curious why they changed the pads unless it's just a more common part number among other hondas.
 

Mellow

Joe
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Joe you've had both right? Do you notice any improvement in braking with the new design?
Curious why they changed the pads unless it's just a more common part number among other hondas.
Difference between 2003 and 2008 ST1300 braking:
None whatsoever.. both were ABS models and both were incredible brakes.

Part compatibility:
Actually, you could interchange Wing and maybe VTX front/rear brake pads with front/rear brake pads on a PRE-2008 ST1300.

So, the change could not have been motivated by common parts.. I'm thinking there were enough rear brake issues related to the SMC for honda to throw some spare dollars on redesigning the front brakes..
 

Blrfl

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Has anybody tried (successfully or unsuccessfully) to cut their own slot into their SMC to copy the factory's "new and improved" version? I don't see how there could be adverse effects from doing this - only positives - but then again, my vision's not always 20-20.
Without knowledge of what alloys and casting process were used to make the part, I don't advise trying to machine it.

Hmmm anyone up for pestering the authorities for a recall of this item? If it needs to be checked every time you ride that is a problem...
Go right ahead, I'll watch. Get on them about your tires, too.

--Mark
 

safedoctor

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Hmmm anyone up for pestering the authorities for a recall of this item? If it needs to be checked every time you ride that is a problem...
Honda does know this can be a problem and it is on their service list that they will do at N/C. Just ask your dealer to check the Vin. in the computer or on the bike where the Vin. is stamped when they do this service you will see a punch mark an the bottom of the J or the side I don't remember which and the is an other service that is marked in the other place. My 04 has both done.
 

Mellow

Joe
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Honda does know this can be a problem and it is on their service list that they will do at N/C. Just ask your dealer to check the Vin. in the computer or on the bike where the Vin. is stamped when they do this service you will see a punch mark an the bottom of the J or the side I don't remember which and the is an other service that is marked in the other place. My 04 has both done.
Actually.. that was the PVC, not the SMC..

https://www.st-owners.com/forums/showthread.php?2349-ST1300-Brake-Proportioning-Control-Valve-(Bike-Years-2003-2004)

They should still fix any SMC issues as long as your bike is under warranty.
 

safedoctor

Flip
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They call it the Linked Brake System / PCV Leakage

To check look at the Vin. stamping in front of the J there will be a round punch mark.

I found my note paper.

The other problem with mine was

Ground Connector Cap Replacement that one the mark is under the J.
 

safedoctor

Flip
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Thanks for that. Prolly something I will do myself but its reassuring to know Honda is on top of this. Who knows maybe its already done. I saw a punch mark on the VIN but thought it was for the ground harness deal.
Mine has 2 munch marks and if Honda want's to do it at N/C I'd let them.
 
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Mine has 2 munch marks and if Honda want's to do it at N/C I'd let them.
The PCV (proportioning control valve) recall for 03/04 does not check the SMC although it does excercise it during the diagnostic. The recall is checking for a leaky PCV valve.

All recalls are done at no charge without regard to time frame.
If you don't have punch marks it either wasn't done or it was done and the dealer forgot to mark it and it will be in their Dealer Repository Report.
 
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Kitchener Ontario
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Difference between 2003 and 2008 ST1300 braking:
None whatsoever.. both were ABS models and both were incredible brakes.

Part compatibility:
Actually, you could interchange Wing and maybe VTX front/rear brake pads with front/rear brake pads on a PRE-2008 ST1300.

So, the change could not have been motivated by common parts.. I'm thinking there were enough rear brake issues related to the SMC for honda to throw some spare dollars on redesigning the front brakes..


Hi Joe, I am pulling this quote from an old SMC thread as I am putting my 04 up for the winter (regretfully) and must replace pads for next season. A recent development is noise from the rear brakes while pushing which leads me to believe that rears are dragging so I am researching SMC problemss in that regard. I have been looking for ebc fa261hh here in Canada that do not charge an arm and a leg for shipping. My motivation? Local dealer is asking $60 per pr. (times 3 pair plus tax). I can get fa261/2hh (which I believe is the gold wing pad you refer to) with free shipping from Amazon.ca. Can you confirm interchangeability of these pads?
 
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Hi Joe, I am pulling this quote from an old SMC thread as I am putting my 04 up for the winter (regretfully) and must replace pads for next season. A recent development is noise from the rear brakes while pushing which leads me to believe that rears are dragging so I am researching SMC problemss in that regard. I have been looking for ebc fa261hh here in Canada that do not charge an arm and a leg for shipping. My motivation? Local dealer is asking $60 per pr. (times 3 pair plus tax). I can get fa261/2hh (which I believe is the gold wing pad you refer to) with free shipping from Amazon.ca. Can you confirm interchangeability of these pads?

The 261/2hh is the thicker version of the 261hh and fits on all year st1300's REAR. I've used both the 261 and 261/2 on the rear on my 04.
Note a lot of web sites are confused as EBC's catalog was wrong for years.
 
Joined
Oct 23, 2009
Messages
28
Location
Huntsville, Alabama
I've read a few threads here how the SMC can cause some problems on the ST1300.

Also - the newer SMC's have a slot for water drainage instead of a hole. Has anybody tried (successfully or unsuccessfully) to cut their own slot into their SMC to copy the factory's "new and improved" version?
Any updates on the modification ?

I have my SMC apart and would like to do any thing to keep from doing this job again....

Don
 

dduelin

Tune my heart to sing Thy grace
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Any updates on the modification ?

I have my SMC apart and would like to do any thing to keep from doing this job again....

Don
I'm a firm believer that if the fluid is replaced and bled by the numbers every 12,000 miles or 24 months the stock system works as designed for a very very long time.
 
Joined
Jan 8, 2011
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Location
Arizona
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2007 Honda ST1300A
Any updates on the modification ?

I have my SMC apart and would like to do any thing to keep from doing this job again....

Don
Don, I sent you a pm, if you'd like to chat I will call you on the white courtesy phone.
 
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