Gus1300
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Secondary Master Cylinder Information
- Thread starter Igofar
- Start date
Don't know the details. Looks like a few guys on the ST EU board got together with a spring manufacturer and had a batch of them made a few years ago and the ones who have been using it since then just swear by it. I suppose you probably follow these EU characters as well?
Am not good enough with springs to figure out if it is is stronger just by looking at it. More coils makes it weaker (lower rate) but the larger wire makes it stronger, hard (for me) to know which way it goes without running the numbers, and then there is free length vs installed length. It could have been designed for about the same force but lower stress than the OEM, to prevent setting and weakening over time.
Typically a spring designer will optimize the design for the spring to be as cheap as possible, minimum material, which means smallest wire diameter and number of coils possible, with smallest safety margin allowed against yield. When you make huge qties of these, it adds up. I suspect a Honda Eng wouldn't be promoted for designing a spring as expensive at this EU one.
stopper bolt is "crooked" ... @jfheath explains in the post that follows, but it's pretty obvious ...
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Gus1300
Site Supporter
Thanks, saw that, but the head flange also doesn't look like it's flat against its mating surface. It looked to me like the bolt is just sitting off kilter, not bent. Wasn't sure that's what I should have been looking for as there's no way to tell whether the hole size is allowing that play or whether the hole itself is not oriented at 90 degrees. Or that it was crossthreaded as explained. (I focused on the picture vs the text...)
Always learning...
larryg
Site Supporter
Could you please post a link to that EU ST board ?
Not sure about policy for posting links to ST boards here, but a search for "Forum for Pan-European" will get you right there.
Afternoon all. This is my first post.
Joined the forum to attempt to tackle an issue I’ve had with my 2010 ST1300A. I have a sticking rear brake that seems to be a regular issue on these bikes.
So far, I’ve replaced the rear brake pads and rotor, and rebuilt the rear caliper, bled and refilled the system following the service manual instructions. Still have the same issue with it sticking.
From what I’ve read here so far, it appears the secondary master cylinder and proportional control valve could be the issue?
Any help would be greatly appreciated. I’ve unfortunately only been able to get about 500 miles on this bike since I bought it.
Joined the forum to attempt to tackle an issue I’ve had with my 2010 ST1300A. I have a sticking rear brake that seems to be a regular issue on these bikes.
So far, I’ve replaced the rear brake pads and rotor, and rebuilt the rear caliper, bled and refilled the system following the service manual instructions. Still have the same issue with it sticking.
From what I’ve read here so far, it appears the secondary master cylinder and proportional control valve could be the issue?
Any help would be greatly appreciated. I’ve unfortunately only been able to get about 500 miles on this bike since I bought it.
Kevcules
Site Supporter
Larry (igofar) is probably smiling right now. He must have sensed this question by now. He's the brake whisperer.
Your issue is more than likely your SMC. Search it on here and ask or call Larry for some advice.....
OP
OP
Igofar
Site Supporter
How did you know?Larry (igofar) is probably smiling right now. He must have sensed this question by now. He's the brake whisperer.
Your issue is more than likely your SMC. Search it on here and ask or call Larry for some advice.....
I just walked in the door and saw this...
Standing by the white courtesy phone
- Joined
- Mar 18, 2006
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- 2,848
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- 70
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- Ilkley, W Yorkshire, UK
- Bike
- 2013 ST1300 A9
- 2024 Miles
- 000679
- STOC #
- 2570
Good afternoon, @Jersey47, and welcome to the forum. Sorry to hear you are having trouble with your new-to-you bike. It sickening when you spend money on a new 'toy' and it doesn't live up to your expectations. But believe me - it will. And in the hands of someone who will look after it, it will do so for many tens / hundreds of thousands of miles.
That is the commonly held belief. It's not my experience though, and. I would suspect not a common experience for members on this forum - once they have sorted out any issues created by poor maintenance of a previous owner.
'Standing by the white courtesy phone' is an indication that Larry has invited you to get in touch. He has probably sent a private message with a phone number. Check your messages on this website.
Listen to Larry. Unfortunately, We have never met or even talked by phone - I'm in the UK - but over the years we have become good email friends. He will help you get it sorted and tell you how to keep it from happening again.
And if you want something with pictures, diagrams and explanations, I'll point you to some of my own documents that many have found to be useful. There can be nothing better than having it explained by the @Igofar, but having it written down is sometimes useful !
But you managed the last mile home. That is the most important one.
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Get in touch with @Igofar ASAP. He will speak to you and have you do a few test to determine what could be wrong. He accurately diagnoses my frozen SMC over the phone. He pointed me in the right direction for parts, how to and within 3 hours I had new brake pads, installed the SMC and bled all 7 brake lines. Happy and Safe riding!
- Joined
- Mar 18, 2006
- Messages
- 2,848
- Age
- 70
- Location
- Ilkley, W Yorkshire, UK
- Bike
- 2013 ST1300 A9
- 2024 Miles
- 000679
- STOC #
- 2570
Hi to ST Owners - my first post.I'll answer that for @ojm Larry - since he is in Europe
Oh, Welcome @ojm. I missed that it was only your 2nd post.
There are a few good places in Europe. This is one that I have used in the past.
Genuine Honda Parts & Spares - UK & Europe's #1 | MSP
Shop Honda parts and spares from Europe's largest spare parts provider. Fast and safe delivery worldwide from reliable couriers.www.motorcyclespareparts.eu
Please note - you list your bike as a 2005 model, but check the white label on the frame under the seat - my guess is that it will indicate a 2004 model. In which case it will state ST1300 4 or ST1300A-4 (the letter 'A' indicates whether it has ABS or not). If the label says '4' or 'A4' you need to give 2004 as your bike's year.
The website doesn't list a 2005 model, and I know that there was not a 2005 model in the UK. It might have been built in 2005, but using the 2004 specs. All models up to 2006 use the same L Brake caliper.
You need the complete part - labelled on this diagram as #2 - I've highlighted the outlined bit - it comes pre-assembled. Check the diagram for the details that you enter onto the website.
You will find it under the section 'L Front Brake Caliper' after you have entered the Brand, Type, Year, Model.
I have been reading many of the posts about the SMC, as I am in the middle of doing re-work of whole brake system during winter layup. I have a 2005 ST1300 (US model) that I bought used with 44,000 mi., and the only reason I started working on the brake system was that the book said I needed to change fluid in 12,000 mi. intervals (haven't done it before). As I get deeper into the project, it keeps getting bigger, with more and more bits to replace. Everything seems doable up to the part where I encounter the SMC. I haven't taken it apart yet, but just encountered the picture above.
I thought I might replace the part labeled (#20), and was not sure which part number to choose (45620-MCS-G04 ?) since there are 4 listed, but this indicates I should replace the entire unit (#2), casting and all. Is that the way to eliminate the problems that seem to be troubling all ST owners? Thanks for your help.
Sadlsor
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- Joined
- Jan 15, 2020
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- 4,271
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- 66
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- Birmingham, Alabama
- Bike
- 2008 ST1300A
- STOC #
- 9065
Glad to have ya! Yeah, I guess being up there in the frozen tundra, you will have SOME time to work on these things for a while.
So you bought a used 15-year-old bike, with an average of under 3000 miles per year. As you ultimately pore over all the brake threads archived herein (and you will want to hit at least 2 of them; look for @jfheath as authoring one of the better ones.)
It's not the mileage that gets ya, it's the sitting around for extended periods of time, unridden. As yours undoubtedly has.
The Secondary Master Cylinder (also search for articles titled thusly) is often the culprit, and without re-hashing the articles (Look in the blue bar atop your computer screen), they become recalcitrant and protest the unfairness of being relegated to dirty clothes racks in the laundry room, while we know that God and Honda made them to be munching miles on all the highways and byways betwixt here and yon.
Even for a non-experienced, terrified-of-the-unknown-and-unfamiliar kinds of novice bike mechanics, you will be amazed at what can be, and what has been, successfully undertaken by folks, with the expert guidance and support by those on this forum.
@Igofar will become one of your best friends.
He walked me through replacement of my Secondary Master Cylinder over the telephone, when I experienced this same scary scenario. Mine is a 12-year-old ST1300, bought with 8300 miles on the clock. So yeah, she had been sitting for an extended period as well.
Be sure to check back here for a personal message from Larry - check for a red flag near your profile at the top-right of the screen.
Enjoy the wrenching, then enjoy the ride!
So you bought a used 15-year-old bike, with an average of under 3000 miles per year. As you ultimately pore over all the brake threads archived herein (and you will want to hit at least 2 of them; look for @jfheath as authoring one of the better ones.)
It's not the mileage that gets ya, it's the sitting around for extended periods of time, unridden. As yours undoubtedly has.
The Secondary Master Cylinder (also search for articles titled thusly) is often the culprit, and without re-hashing the articles (Look in the blue bar atop your computer screen), they become recalcitrant and protest the unfairness of being relegated to dirty clothes racks in the laundry room, while we know that God and Honda made them to be munching miles on all the highways and byways betwixt here and yon.
Even for a non-experienced, terrified-of-the-unknown-and-unfamiliar kinds of novice bike mechanics, you will be amazed at what can be, and what has been, successfully undertaken by folks, with the expert guidance and support by those on this forum.
@Igofar will become one of your best friends.
He walked me through replacement of my Secondary Master Cylinder over the telephone, when I experienced this same scary scenario. Mine is a 12-year-old ST1300, bought with 8300 miles on the clock. So yeah, she had been sitting for an extended period as well.
Be sure to check back here for a personal message from Larry - check for a red flag near your profile at the top-right of the screen.
Enjoy the wrenching, then enjoy the ride!
- Joined
- Mar 18, 2006
- Messages
- 2,848
- Age
- 70
- Location
- Ilkley, W Yorkshire, UK
- Bike
- 2013 ST1300 A9
- 2024 Miles
- 000679
- STOC #
- 2570
Sorry - Forgot to say welcome to the forum and to your new-to-you ST1300.
The SMC is a good bit more expensive than the part #20, but nothing more than a few tanks of fuel would cost you. Replacing part 20 - commonly known as the service kit - it is quite possibly not going to solve the problem. - especially given the age.
The SMC piston bore could be damaged by corrosion or the very very tiny compensation port could be blocked with crud - and the filter part with its own tiny compensation port, two very find gauze filters and a small spring and seal are not listed as replaceable parts. You may well have to buy the full unit anyway.
Or the bore could have been knocked out of shape.
The circlip is notoriously difficult to get out and in. Buying the complete unit does away with all of the hassle. Get the complete unit, a good handful of copper crush washers and lean how to bleed and flush the brake system properly and it will give you thousands of trouble free miles.
Forget the 12000 mile interval as a guide. Your bike has averaged 2,500 miles per year . If you changed the fluid ever 12000, that would take 5 years between changes. The Brake fluid would be water and crystals by then. Change the fluid every year if you can. I do. It gathers moisture over time. 2 years is the absolute limit.
Note also when you look at the fiches, that your 2005 model has a different SMC from the 2008 and later models. The number at the end - eg you may see G02 or G03 - they don't make much difference - they are compatible with each other.
The 45620 MCS G02 and 45620 MCS G04 seem to differ in the way that the spring and primary seal are arranged inside the bore. So basically the later numbers have slight modifications to the innards. So given the choice you would go for the G04.
For the full SMC in the UK, the 2004 model uses 06454-MCS-G03 for the SMC. (There is no 2005 model in the UK).
Avoid the ones that end with something like R01 or R02 - those are the ones for the 2008 and later models and are not compatible.
The SMC is a good bit more expensive than the part #20, but nothing more than a few tanks of fuel would cost you. Replacing part 20 - commonly known as the service kit - it is quite possibly not going to solve the problem. - especially given the age.
The SMC piston bore could be damaged by corrosion or the very very tiny compensation port could be blocked with crud - and the filter part with its own tiny compensation port, two very find gauze filters and a small spring and seal are not listed as replaceable parts. You may well have to buy the full unit anyway.
Or the bore could have been knocked out of shape.
The circlip is notoriously difficult to get out and in. Buying the complete unit does away with all of the hassle. Get the complete unit, a good handful of copper crush washers and lean how to bleed and flush the brake system properly and it will give you thousands of trouble free miles.
Forget the 12000 mile interval as a guide. Your bike has averaged 2,500 miles per year . If you changed the fluid ever 12000, that would take 5 years between changes. The Brake fluid would be water and crystals by then. Change the fluid every year if you can. I do. It gathers moisture over time. 2 years is the absolute limit.
Note also when you look at the fiches, that your 2005 model has a different SMC from the 2008 and later models. The number at the end - eg you may see G02 or G03 - they don't make much difference - they are compatible with each other.
The 45620 MCS G02 and 45620 MCS G04 seem to differ in the way that the spring and primary seal are arranged inside the bore. So basically the later numbers have slight modifications to the innards. So given the choice you would go for the G04.
For the full SMC in the UK, the 2004 model uses 06454-MCS-G03 for the SMC. (There is no 2005 model in the UK).
Avoid the ones that end with something like R01 or R02 - those are the ones for the 2008 and later models and are not compatible.
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Sadlsor
Site Supporter
- Joined
- Jan 15, 2020
- Messages
- 4,271
- Age
- 66
- Location
- Birmingham, Alabama
- Bike
- 2008 ST1300A
- STOC #
- 9065
I went with the "buy-a-new-one" plan, and am glad I did.
However, I did keep the original SMC, and will later on purchase the rebuild kit (much cheaper), on the off-chance I may be able to keep it as a spare.
Thing is, now that I own this machine, I can say without reservation that it will most assuredly, NOT sit around in the laundry room or the garage, neglected and ignored as it did with the previous owner.
As a motorcycle owner, I take seriously my responsibility to ride the doggone thing!
Thanks for your help.
I guess I may have worded that to be a bit misleading. I did buy my ST used, but is was 2016, and it had 29,000 mi then. I have no excuse for not bleeding brake system, except "if it works, don't fix it". I will be changing fluid regularly from now on. The truth is, I didn't notice any problem with my brakes.
After draining and taking my calipers apart, it seemed like I might have run into problems in the near future, however, since the pistons seemed pretty hard to move. I was able to get them out with air pressure.
Ever since then, I have been trying to decide what to do about the SMC. Holding it in my hand, it seems to stick when pushed in. That is why I have been reading over these posts.
Since reading your latest post, I looked at the part number for the #2 part for both 2005 and 2010 and they are different as you mentioned.
The part number for 2005 is 06454-MCS-G03 and for 2010 it was 06454-MCS-R02. I will order the G03 unit since it is listed for my 2005.
Thanks again for all the help that is available in these forums.
I guess I may have worded that to be a bit misleading. I did buy my ST used, but is was 2016, and it had 29,000 mi then. I have no excuse for not bleeding brake system, except "if it works, don't fix it". I will be changing fluid regularly from now on. The truth is, I didn't notice any problem with my brakes.
After draining and taking my calipers apart, it seemed like I might have run into problems in the near future, however, since the pistons seemed pretty hard to move. I was able to get them out with air pressure.
Ever since then, I have been trying to decide what to do about the SMC. Holding it in my hand, it seems to stick when pushed in. That is why I have been reading over these posts.
Since reading your latest post, I looked at the part number for the #2 part for both 2005 and 2010 and they are different as you mentioned.
The part number for 2005 is 06454-MCS-G03 and for 2010 it was 06454-MCS-R02. I will order the G03 unit since it is listed for my 2005.
Thanks again for all the help that is available in these forums.
Sadlsor
Site Supporter
- Joined
- Jan 15, 2020
- Messages
- 4,271
- Age
- 66
- Location
- Birmingham, Alabama
- Bike
- 2008 ST1300A
- STOC #
- 9065
I actually rode mine for about 8 to 9 months, with no brake issues either. I was "going to get around to it" too, but we basically have about 364 riding days out of a year, here in Alabama, ...so I didn't find my 'roundtuit.
Until I had to.
But now that you've observed the SMC sticking, I submit to you that you're on the right track. You can do this!
I went with the "buy a new one plan", and now I have a brand new 06454-MC5-G03 SMC in my hand (the one listed for 2005). I did take the old one apart before ordering the new one, and yes, it was a little crusty in the end of the cylinder under the washer and snap ring.
My question is, do I need to take the brand new one apart to add silicone grease in the top, or has that been taken care of from the factory?
I thought someone might know the answer to this before I take it apart to find out.
My question is, do I need to take the brand new one apart to add silicone grease in the top, or has that been taken care of from the factory?
I thought someone might know the answer to this before I take it apart to find out.
Whoops-that would be 06454-MCS-G03. I discovered that the 5 was actually an S after I cleaned my glasses.
Thanks for the help.
Thanks for the help.