Rear brake system

jfheath

John Heath
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I'm finally down the home stretch with my brake system rebuild. SMC is rebuilt, rear caliper is cleaned and all new seals are in, even found some silicon grease. Then I took one more look at the manual and noticed that I should be replacing bolts. Lots of them. Along with sealing washers. I'm not cheap but when all was totaled, it came to over 100 bucks!!! So my question is, who among all that have done this stuff has replaced these bolts? The washers I understand but the bolts are hard for me to swallow.
Yes, I replaced the 3 rear calliper joining bolts an the front caliper mount bolts both sides. The banjo union brake line bolts (oil bolt) do not need to be replaced according to my 2002 shop manual.

Personally, I tend not to replace the mounting bolts every time - maybe every other time - I clean them up, inspect the threads and apply thread locking compound - but the manual is very clear - replace with new. I always have a complete new set in stock, but I cannot recommend following my bad example. Ditto the rear caliper stopper bolts. These bolts are described as ALOC - but none of the Honda dealers know what this stands for. The suggestion is just they have thread lock compound already in place. The rear master cylinder mounting bolt 12Nm/9ftlb is an ALOC bolt and I can't think of any reason why that (other than thread locking) should have any special qualities. But these are just my own thoughts and since I am making big assumptions. Follow the manual is the best advice.

The banjo union crush washers also need to be replaced with new each time. I buy them from the local dealer who uses copper crush washers for a few pence each - but I ordered 20 for the front SMC and rear caliper. Like the oil sump bolt, they deform when they are tightened and if they are to provide a leak proof seal, must be replaced. People say that they clean them up and re-use - but they cannot then mould themselves into the casting or the bolt head as they will not crush any more. The answer with these is always to have a few in stock.

The bolts for the two caliper halves of the rear caliper: I know that some cylinder head bolts are use once only stretch bolts, so they are deformed by the action of tightening to the correct torque. I thought it was possible that these bolts were like that - but I have no way of knowing if this is the case. I just fitted new.

There's one way of looking at the expense of stuff like this. I change my oil every 4-6K miles. I use fully synth, and I can tell from the feel of the engine when it is time to change again. The point is that 4litres (UK) of fully synth oil costs around £36. After which it gets thrown away. Same with fuel. I have to fit new fuel every 280 miles or so, the Honda ST1300 disposes of it as it wears out. But a new fuel costs around £35 each time. Fortunately it is a spare part that is quite easy to obtain, and I'm happy to use non-OEM stuff for that.
 
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OP
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California
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2004 ST1300
I have to break down and put my ego aside and ask for some MORE help! I removed the rear wheel, caliper, then cleaned everything, rebuilt the caliper then reinstalled everything. Bled the system and everything is good. Then I removed the SMC, rebuilt that, added new crush washers, then filled the reservoir and that's when my problem started. When I squeeze the brake lever then release,
bang!, air comes back into the reservoir. I've bled brakes on 10 different cars, 20 bikes and a few helicopters. Never had a problem. I've used my Mighty Vac, the MotionPro and old fashioned tube in a container method. Any ideas at this point would be greatly appreciated.
 

Andrew Shadow

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In my experience, and for reasons unknown to me, I find that motorcycle master cylinders are more prone to developing air locks than car master cylinders. I would try bleeding the master cylinder directly at the master cylinder outlet before looking any further- it is simple and quick to do.
 

ST Gui

240Robert
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Helos have brakes to slow and stop the rotation of the rotors.

Air brakes are an extra cost option.
 

jfheath

John Heath
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I have to break down and put my ego aside and ask for some MORE help! I removed the rear wheel, caliper, then cleaned everything, rebuilt the caliper then reinstalled everything. Bled the system and everything is good. Then I removed the SMC, rebuilt that, added new crush washers, then filled the reservoir and that's when my problem started. When I squeeze the brake lever then release,
bang!, air comes back into the reservoir. I've bled brakes on 10 different cars, 20 bikes and a few helicopters. Never had a problem. I've used my Mighty Vac, the MotionPro and old fashioned tube in a container method. Any ideas at this point would be greatly appreciated.
Yes - that can be normal behaviour. The master cylinders are quite high up in relation to the rest of the circuit, and any air in that part of the hose has nowhere to go. It will slowly seep through the tiny compensation port when the brake lever or pedal is relaxed (but may need help). Also any air that enters when the reservoir runs dry will take a little time to return, which it will do when the lever/pedal is pumped.

If doing the front, it is a good idea to turn the bars completely to the left and then to the right to allow any air to work its way out of that part of the system. Replace the reservoir cap before turning to the right though. What ? Too late ? !! Also tap the banjo union when bleeding to dislodge any air bubbles that have attached themselves to the joint. (see the video in post #11 at https://www.st-owners.com/forums/showthread.php?156754-ST1300-Getting-all-the-air-out-of-the-brake-system&highlight= - also the pdf in post#1 has much more detail than the pics in post#11)

It is probably a small error, but just for anyone else who reads it - you mention that squeezing the brake lever after servicing the SMC produced the air in the reservoir. The brake lever (handlebar) has absolutely no effect on the SMC circuit - it operates the circuit from the front lever master cylinder to the outer pistons in each of the two front callipers, and that is all.

The brake pedal operates the centre piston of the rear caliper directly, and another line from the rear master cylinder operates the centre piston in each of the front calipers, provides fluid to the SMC, and when the bike is not moving, it then feeds the two outer pistons in the rear caliper (via the proportional control valve). Getting air out of this rear circuit requires that the correct sequence is followed - and it usually needs a few iterations of this cycle before all of the air is removed.

I think the vacuum bleeders are an essential tool for getting a decent flow of fluid through the system to shift the air (see that video again). But vacuum bleeders will suck air past the threads on the bleed valves, even if they are wrapped in Teflon tape as recommended. I find it necessary to finish off with a normal bleed tube and a non return valve. The normally recommended way of open bleed valve, squeeze lever/pedal, close valve, release and repeat ad nauseum doesn't work very well. This is because when you close and release, the air bubbles have time to flow back up to the top of the nearest bend in the tube. The vacuum pump and the non return valve enable a reasonable flow of fluid to be maintained to keep the bubbles moving. Nevertheless, tapping tubes and joints is still necessary - as is flexing the hoses especially behind the headlights.

Larry reckons that sometimes air bubbles can get trapped in the banjo unions, and they need to be cracked open to release it. I haven't found that to be necessary yet, but Larry has, and he has much much more experience than I have.

Read the pdf file mentioned previously. It might help to understand what is going on in the system.
 
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Andrew Shadow

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I think the vacuum bleeders are an essential tool for getting a decent flow of fluid through the system to shift the air (see that video again). But vacuum bleeders will suck air past the threads on the bleed valves, even if they are wrapped in Teflon tape as recommended.
Many years ago I use to work as a mechanic on vehicles having 4 or more wheels. One tool we used to bleed brake systems was a brake pressure bleeder. It bled the brakes by pressurizing the system to 30 P.S.I.G. at the master cylinder and introducing a continuous flow of new brake fluid. The brake fluid would flow for as long as you kept a bleeder open. This system was also very efficient at flushing all of the contaminants out at the same time. It eliminates the problem that vacuum bleeders create of air being drawn in to the system as the system is always at positive pressure. I never hear of such a bleeding system anymore.
 

jfheath

John Heath
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Many years ago I use to work as a mechanic on vehicles having 4 or more wheels. One tool we used to bleed brake systems was a brake pressure bleeder. It bled the brakes by pressurizing the system to 30 P.S.I.G. at the master cylinder and introducing a continuous flow of new brake fluid. The brake fluid would flow for as long as you kept a bleeder open. This system was also very efficient at flushing all of the contaminants out at the same time. It eliminates the problem that vacuum bleeders create of air being drawn in to the system as the system is always at positive pressure. I never hear of such a bleeding system anymore.
They sound like a good idea, but I have heard say that pressure systems are not a good idea on the ST1300 - I don't know why, since brake fluid is pressured that way from the master cylinder anyway. Maybe my source was wrong. I have never been able to try one.

I used to have a kit that worked on this principle by a firm called Gunson - but it was designed for cars and had fittings for typical car master cylinder reservoirs that have screw caps. It used air pressure from the vehicle's tyre and had a cap which replaced the cap on the reservoir, feeding in fresh fluid from its own bottle. Trouble was, it didn't have anything that remotely resembled the caps on motorcycle fluid reservoirs. There would remain the need for flexing tubes, tapping joints and general bubble chasing on the ST1300, not to mention exercising the SMC and tilting it. Some of these bubble simply do not shift unless they are given the right sort of help - even in a steady flow of sucked or blown fluid.
 
OP
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Like Clint said, " man's got to know his limitations." I've found mine. Anyone know a really good ST mech near the Antelope Valley Ca.?
 
OP
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So I called the local independent repair shop here in town, since all the dealers except HD have closed, and he won't touch it. Kept prattling on about having to disconnect the ABS motor and how it's a dealer only tool you need. Then I called the closest dealer, 35 miles, and he said the same thing. But for $230 bucks he could have it done in a day. No wonder people try to be their own mechanic. Nowhere in the manual does it say to touch the modulator or control unit when bleeding brakes. VERY frustrated right now!!!
 
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The rear brake on my '07 ST 1300 locked up, boiled the brake fluid and blew the line right off the brake caliper body. Limped home with only the front brake at no more than 20 mph. Called Honda in California. Told to take bike to local Honda dealer to take photos and send to them. Bike has been in local dealer since Nov. 15, 2017. I have been through three service managers & calls to Honda in California. Several people shared their wisdom and insights with me on this site and by word of mouth. No progress at all. They never heard of anything like this. I call every Friday afternoon and they are still working on it. Going on five months. Maybe they are waiting for the Emperor or the Diet (Japanese Parliament) to grant permission to fix it or getting back at me for the Bomb? Any other reason makes about the same sense to me now. Very frustrating. March 28, 2018.
 

Andrew Shadow

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No disrespect intended but I think that you need to get your bike to a different shop. Even if they truly have never heard of anything like this before it should not take a professional shop three months to diagnose a brake problem- especially if Honda is really involved. Something is not right there! There are a few really knowledgeable ST1300 guys who are in Florida. I have no idea how close any of them are to you. Maybe ask if one of them can look at the bike with you. If it is a seized SMC (which is what it sounds like at first read) that does not take long to diagnose. If it isn't, because of their knowledge and experience, they might see something else going on and have suggestions for you.
 
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PM me a contact phone number and I'll call you and see If I can help.
Email sent
 
OP
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So an update...After reading everything you all were kind enough to post and a phone call from Igofar, I've been on the road and putting miles on my bike. Also, the brake bleeding sequence that Jfheath posted was great. I printed out a copy and was able to go back to it several times to make sure I bled everything twice. Now my brakes are better than ever! And to answer Trapperdog's question, I was a CH-46 crew chief in the Marine Corps and yes, we had fixed landing gear with tires and brakes. Those brakes sucked when bleeding cause you had to do it inside the chin bubble and it was always a 2 man job. No room to move and always a messy job. Plenty of videos on youtube if you wanted to check them out. Also, thanks to SuperSaber for that disc!! Really saved me some cash.
 
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