.. mine moves a little bit.. but I thought it was normal..
and on this occasion I ask you all: when it is parked, the SMC must not move at all..? his move must be '0'..?
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Front fork noise when going over obstacles
- Thread starter cricu
- Start date
and on this occasion I ask you all: when it is parked, the SMC must not move at all..? his move must be '0'..?
- Joined
- Mar 18, 2006
- Messages
- 2,874
- Age
- 70
- Location
- Ilkley, W Yorkshire, UK
- Bike
- 2013 ST1300 A9
- 2024 Miles
- 000679
- STOC #
- 2570
You should be able to move the SMC bracket forward by pressing the rear of of the top part forward towards the fork, but it is not an easy press, it requires a small amount of effort. And the movement is only a tad more than 1mm - and that is enough to stop the rear wheel from turning, and releasing it again when the SMC is not being pressed.
If it clunks, then there's something not right.
If it clunks, then there's something not right.
I made 3 videos so you can see exactly what is happening.. the first is with the movement of the SMC. the 2nd, is with the rotation of the wheel, with the SMC pushed by hand. and the 3rd, is with the rotation of the wheel without the SMC being pushed.
https://youtube.com/shorts/yYooF0t9deE
https://youtube.com/shorts/L8-gbhTdJig
https://youtube.com/shorts/jbeunpOqBMY
Kevcules
Site Supporter
Sounds like a lot of play in your SMC. Again, try the bleeding sequence first.
You might hear that SMC go clunk clunk as you hit uneven spots in the pavement. Try pressing the front brake (slowing down) while going over a bad spot in the road. The SMC will be pressed up and shouldn't make any noise while the front brake is on slowing down.
Lay down beside your bike on the left side. Rotate the rear tire with your foot and then quickly press up on your SMC. The rear tire should stop right away. Then release your SMC and try spinning the rear tire again. It should release the rear brake right away.
Good luck.
You might hear that SMC go clunk clunk as you hit uneven spots in the pavement. Try pressing the front brake (slowing down) while going over a bad spot in the road. The SMC will be pressed up and shouldn't make any noise while the front brake is on slowing down.
Lay down beside your bike on the left side. Rotate the rear tire with your foot and then quickly press up on your SMC. The rear tire should stop right away. Then release your SMC and try spinning the rear tire again. It should release the rear brake right away.
Good luck.
Andrew Shadow
Site Supporter
Your SMC either has a lot of air in it or it is shot. There is no way that you should be able to move it that easily. You can do so because it is not pressurizing any brake fluid. I suspect that the piston is seized in the SMC bore and that you need a new SMC.
Try bleeding the brake system first and then doing a functional test, you have nothing to loose.
Try bleeding the brake system first and then doing a functional test, you have nothing to loose.
After replacing hundreds of SMC’s on these bikes over the past several years, I’ve seen one major flaw in folks explaining, and inspecting these units etc.
Most, if not all, folks have never seen or inspected a new and undamaged unit, so they have no reference point as to know what feels/looks normal.
I’ve removed too many seized up units that the owners felt were normal (they all do that) not knowing they were on the edge of having their bike lock up the rear wheel and toss them off.
Folks think 1-2mm of movement is normal, yes, but are they really feeling free movement, or dead space because the piston is stuck in the bore etc.
If you want to see if your feeling pressure, or damage, place a bleed hose on the PCV, open it up to relieve the pressure, and see if you can then move the piston it’s full length.
Most folks are surprised when it still won’t move more than a millimeter or two because it’s stuck etc.
And yes, even when the piston is stuck in the outward end of the bore, you can press hard enough to stop the wheel, but that does not mean it’s working properly or safely.
Most, if not all, folks have never seen or inspected a new and undamaged unit, so they have no reference point as to know what feels/looks normal.
I’ve removed too many seized up units that the owners felt were normal (they all do that) not knowing they were on the edge of having their bike lock up the rear wheel and toss them off.
Folks think 1-2mm of movement is normal, yes, but are they really feeling free movement, or dead space because the piston is stuck in the bore etc.
If you want to see if your feeling pressure, or damage, place a bleed hose on the PCV, open it up to relieve the pressure, and see if you can then move the piston it’s full length.
Most folks are surprised when it still won’t move more than a millimeter or two because it’s stuck etc.
And yes, even when the piston is stuck in the outward end of the bore, you can press hard enough to stop the wheel, but that does not mean it’s working properly or safely.
My money says your SMC is locked up.
ok, so I'm not wrong that I change the whole SMC, it's clear that it has a problem, correct..? I guess you saw the videos I posted..After replacing hundreds of SMC’s on these bikes over the past several years, I’ve seen one major flaw in folks explaining, and inspecting these units etc.
Most, if not all, folks have never seen or inspected a new and undamaged unit, so they have no reference point as to know what feels/looks normal.
I’ve removed too many seized up units that the owners felt were normal (they all do that) not knowing they were on the edge of having their bike lock up the rear wheel and toss them off.
Folks think 1-2mm of movement is normal, yes, but are they really feeling free movement, or dead space because the piston is stuck in the bore etc.
If you want to see if your feeling pressure, or damage, place a bleed hose on the PCV, open it up to relieve the pressure, and see if you can then move the piston it’s full length.
Most folks are surprised when it still won’t move more than a millimeter or two because it’s stuck etc.
And yes, even when the piston is stuck in the outward end of the bore, you can press hard enough to stop the wheel, but that does not mean it’s working properly or safely.
From the sound/look of your video, I would suspect your unit is stuck.
Do NOT try to rebuild it, as a new piston/spring/seal will not correct a damaged bore, or clogged up cartridge etc.
Purchase the entire unit.
You will also need 4 oil lock washers too.
If your comfortable working on your own bike, it’s a pretty simple swap, then the entire system needs to be flushed and bled correctly.
If you want to verify it for sure, remove pressure from PCV and check piston/bore movement, and gently lift up rubber boot on SMC and see if you see rust!
Do NOT try to rebuild it, as a new piston/spring/seal will not correct a damaged bore, or clogged up cartridge etc.
Purchase the entire unit.
You will also need 4 oil lock washers too.
If your comfortable working on your own bike, it’s a pretty simple swap, then the entire system needs to be flushed and bled correctly.
If you want to verify it for sure, remove pressure from PCV and check piston/bore movement, and gently lift up rubber boot on SMC and see if you see rust!
Start cheap and simple, grab, shake and bump and make sure forks are mounted straight. I have a St with 120,000 miles on it and haven't had any problems with the brakes or fork at all. but I was born lucky.
I AM NOT IN ANY SHAPE OR FORM JUDGEING ANYONE FOR THEIR POSTS OR WHAT THEY ARE SAYING. WE ALL HAVE DIFFERENT EXPIERIENCES. Their help is irreplaceable, and valuable. I have used them in the past and will use them in the future
There is a lot of stuff under the fairing and something might be just loose.
I have always found the fluid changes are the first thing to do when buying a knew bike though, most short term owners don't maintain their bikes like long haulers. Also with aluminum used in engines and components the cooling system should not be overlooked.
I have a ZRX that had a buzzing noise towards the front when I shifted at the medium range right before a shift, sounded like valves. Adjusted them and found problem inside bikini fairing with wiring harness, held fairing while revving. Weird how the front focused engine rpm to that area. I tell myself the valves needed adjusting anyway.
I AM NOT IN ANY SHAPE OR FORM JUDGEING ANYONE FOR THEIR POSTS OR WHAT THEY ARE SAYING. WE ALL HAVE DIFFERENT EXPIERIENCES. Their help is irreplaceable, and valuable. I have used them in the past and will use them in the future
There is a lot of stuff under the fairing and something might be just loose.
I have always found the fluid changes are the first thing to do when buying a knew bike though, most short term owners don't maintain their bikes like long haulers. Also with aluminum used in engines and components the cooling system should not be overlooked.
I have a ZRX that had a buzzing noise towards the front when I shifted at the medium range right before a shift, sounded like valves. Adjusted them and found problem inside bikini fairing with wiring harness, held fairing while revving. Weird how the front focused engine rpm to that area. I tell myself the valves needed adjusting anyway.
Andrew Shadow
Site Supporter
And he may well find something making noise in any of those areas, so he should absolutely do that as well. If he finds something, it will be in addition to his SMC problem.
His SMC is shot based on what is shown in his videos.
Thank you all ! Your advice helps me a lot, because here, no one knows the particularities of this motorcycle.
To be sure, as @ Igofar also says, I ordered the entire unit, 4 oil lock washers and the shaft boot.
I will try to do the bleeding as best as possible. I will do the work myself, because I do not trust the workshops in my area..
To be sure, as @ Igofar also says, I ordered the entire unit, 4 oil lock washers and the shaft boot.
I will try to do the bleeding as best as possible. I will do the work myself, because I do not trust the workshops in my area..
I looked at the fische and can't find the SMC and 4 oil lock washers. Anyone have part numbers or a nonsurgical way to help me find it ona fische?
Attachments
Thanks a bunch. I appreciate it.
A bit of news for you, Cricu, most of the Honda Dealers' mechanics over here don't know these bikes either, which has bred a very widespread distrust of them. One reason help is so readily available on this website is most of us have been stuck at one time or another and been helped here.
You left out half of my operation, Larry. I carved a wooden block to fit tightly between the smc and the fork so it couldn’t depress the smc to activate the rear brake when applying the front brake. The zap strap was to hold the wood block in place and stop the smc from rattling. Worked really well actually. Still had much better brakes than a lot of bikes I have ridden. They worked independently from each other, no more link-braking.
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In my case I helped myself. I had to, I was way up north in Whitehorse. Thankfully I grew up on a farm and my Dad was very adept at adapting and modifying anything to get it to work, and I guess some of that “skill” wore off on me. Fortunately there was a Honda dealer there and he had a set of rear pads in stock and I was able to put them in.
The only thing that is mandatory in a motor vehicle is brakes and steering, the rest is an option
Good tyres help