Have the dreaded rear caliper center piston not releasing...locks the rear wheel.
The ST forum recommends replacing the secondary master cylinder on the left front caliper.
Honda part number 06454-MBG-425 is unavailable. This part number is the same for 1998-2005 VFRs.
The 2006-2009 part number is is 06454-MBT-D52. May fit other years but I stopped searching after model year 2009.
Anyone know if the 2006 part number fits the 1998-2005 model years?
Thanks.
I have one handy, but not sure what model year it's from. I'm in the North part of Anaheim, just a few miles from Long Beach. Message me and let's see if I can help.
Cheers,
D
Shucks...I'm in the Colorado area now...moved from LA several years ago.
Is the one you have handy on or off a bike? Might be able to take some pics and measurements.
Thanks
I just rebuilt the SMC on my '99 with some new AllBalls seals . AllBalls don't have a specific SMC kit but because it is my own bike, I bought a kit for the same same year front brake master using the reasoning that as long as diameter was the same, the seals would interchange, and that does appear to be the case. My SMC was weeping fluid but no longer, and all appears to function correctly (200km test ride yesterday). There's a blue cartridge in the SMC that gets clogged I think, but with care it is easy enough to fully disassemble and clean.
I visually compared the SMCs on my 99 and 09 and they certainly look like the same part, same MC diameter, same pivot distance. I know there's no difference between wheel axle size, disc spacing and disc diameter so I would be surprised if there is a significant difference at the SMC. Is the calliper part number common across all the 6th gens? The part number change could be for a very small difference e.g. paint finish, or there might be a detail difference e.g, in moisture drain hole that was an upgrade.
Thanks for the visual check.
Same part number, 06454-MBG-425 BRACKET SUB-ASSY., L. FR., used on Honda VFR800 Interceptor model years 1998, 1999, 2000, 2001, 2002, 2003, 2004, 2005.
Part number 06454-MBT-D52 used on 2006, 2007, 2008, 2009 model years.
2010 VFR 1200, looking at the parts diagram and doing some additional research, looks like a completely different brake setup.
I'm betting the 2006-2009 part will fit and work.
12 hours ago, vt600cShucks...I'm in the Colorado area now...moved from LA several years ago.
Is the one you have handy on or off a bike? Might be able to take some pics and measurements.
Thanks
Off the bike. I might have another one, but have not dug into that bin as of yet.
Sorry to hear your VFR is acting up.
I am currently in the process of delinking my 5th gen to circumvent this event.
From comparing pictures on the internet (06454-MBT-D52) and the three original ones I have laying around: look very similar, but indeed no guarantees on fitting, fluid displacement and working of SMC.
Why not try to clean your current one as good as possible? Have a look here.
You can also refurbish the 'pump' part with aftermarket part from Tourmax with part number MSB-117.
As stated already, the SMC cannot be purchased separately/new/aftermarket, so if this is remains the culprit after cleaning, a possibility is to buy a second hand 06454-MBG-425 and hope it is in a better condition (after cleaning).
A more impacting option is to delink your VFR.
There are some fancy options to upgrade to a different forks, mentioned here.
I have made the choice to stick to the original front and will replace 06454-MBG-425 with a custom designed bracket combined with 45190-KFG-641 from a NT650V from 2002 (or another rear one, although not fully matching with 'slit' for disc width) .
Also, be sure your rear caliper (pistons / rubbers) aren't the bottleneck.
Appreciate the responses.
I found a new 2009 caliper with an SMC (on Ebay) so I took a chance and purchased it.
The caliper assembly part number is Honda 45150-MCW-H03.
The SMC bolted on exactly as the 2001 SMC. Hard to see in the attached pictures, but the casting on the SMC is 1/2, same as the 2001 SMC.
The 2009 caliper was slightly different. The lower brake hose port is angled versus the 2001 which is straight, like the upper brake hose port. The 2001 short brake hose should be long enough to use on the 2009 slightly angled brake hose port. The second difference was the brake pad pin, the 2009 uses a hex head brake pad pin.
So, as it stands now, Honda part number 06454-MBT-D52 (model year 2006-2009 SMC) can be used for model years 1998-2009 VFRs.
I'll update once all is back together but it will be a while as I plane to rebuild all the calipers and flush all the brake lines, maybe replace them with stainless lines.
[image: image.png.dfda66e44073551de7a0775439a636e5.png]
[image: image.png.9e08f0d2598d529e4657049fa7a7889f.png]
Did you check that the 'slit' in the 2009 secondary master cylinder / caliper mounting bracket has the same offsets towards the brake disc when mounted?
[image: caliper_brake_disc_alignment.jpg.ba0fba9a82f03492b5fecd883135497c.jpg]
The pads were even different sizes. As I recall the calipers were redesigned. I own both sets all have different part numbers including the pads.
Haven't got that far yet.
Would it matter if the 'slit' offset is not the same?
Just playing around with the 2009 SMC, the caliper seems to float on the SMC and might center itself even if the 'slit' offset is not the same.
Thanks for pointing that out as I haven' looked that close.
eric
In practice a 0.5 mm difference on not being identical might work out, but since braking is pretty essential for safety, you must at least look for possible differences and decide if the (possible) impact is acceptable (to you).
For example, the brake disc are a 'floating', you want your braking pads for braking on the disc and not the caliper holder...
I am not sure which caliper you want to place on the 2009 caliper holder, but the glide pins length, the distance between the glide pins (in plane of brake disc), the mounting position (in the direction of the wheel axle), etc. need to be (near) identical.
Any update on the original question of if 06454-MBG-425 and 06454-MBT-D52 are the interchangeable ?
Thank you. You are very helpful. A new 6th Gen SMC will be my last resort due to no availability in new 5th gen SMC. I have read every forum pertaining to the linked brake issues. I am going to take my chances on rebuild kit and removal of the green filter screen. Nobody has mentioned HOW to remove this exactly ? What is the way to remove without damaging. If the answer is compressed air, where do I direct the air exactly ?
8 hours ago, Slide46Thank you. You are very helpful. A new 6th Gen SMC will be my last resort due to no availability in new 5th gen SMC. I have read every forum pertaining to the linked brake issues. I am going to take my chances on rebuild kit and removal of the green filter screen. Nobody has mentioned HOW to remove this exactly ? What is the way to remove without damaging. If the answer is compressed air, where do I direct the air exactly ?
Up to 2009, 5th & 6th Gen use exact same 2nd master cyl, part numbers are identical.
6th Gen front calipers are no use on a 5th Gen, piped up different & piston sizes & how it's linked is different too.
Re:
Green check valve in 2nd master cyl.
Once master cyls off the bike, pull the piston assembly, remove the bolt off brake pipe union that holds the Green return valve in place, O'ring is all that keeps brake fluid in so don't loose it, ideally replace if you can size match it, note valves orientation (Take pics).
To get valve out:
Block off the bottom banjo bolt hole, stuff some rag in, blow into piston bore & green valve will just pop out, I wouldn't use an airline, a good blow with mouth is enough (trumpet style) it's not a tight fit, but it is a snug fit, keep a hand over it, if you lose of damage it, you're fucked, you can't buy em & master cyl can't be used without it, you'd never get a fluid seal on the bolt off pipe union, give the insides lots of love, to avoid scratching stuff I use Ice lolly sticks split in half as pokers with paper towel soaked in brake cleaner to get the gunk shifted from the bottom of the piston bore, when all the schmoo is out, I lightly hone the bore with 2000 wet , dry or a grey scotchbrite to ensure a good fluid seal.
Green return valve has a filter screen on each side, carefully pry it apart, ball bearing & spring is all that's inside, surgically clean it all, along with the bore it came from, there's a micro hole all the way thru the valve, ensure you see daylight thru it, this is held closed by the ball & spring.
If you source a Tourmax repair kit (best available) they come fully assembled, easier to fit to master cyl if you remove the clevis mount from the pushrod.
Have fun😊
Update:
I took the time to rebuild the secondary master cylinder with new seals. I quickly found my issue when I finally popped out the green screened filter. The ball bearing and spring completely full of gunk. I read on a forum here the ball bearing and spring can be removed completely , I know this probably isn’t the correct way but I did not want to take chances with it. I needed clarification on how to remove the filter and was grateful to get the instructions here from Gaz66. Unfortunately mine was slightly stuck in the press fit hole so the “trumpet” method was not enough and I managed to bend a right angle pick back a tiny bit, carefully put it into the cylinder, then through the hole behind the filter to pop it out. This worked for me.
Used a .009 guitar string to free up the microscopic hole inside the filter. Worked perfectly. Reassembled everything while constantly questioning if I put the seals the right direction regardless of telling myself “remember which way they go”.
Flushed the system very thoroughly. Bled everything thoroughly. Cleaned/burned all the brake fluid off the exhaust and she doesn’t lock up anymore. Thank you and now I can focus on the things I want to with the bike and actually enjoy it.