The New And Improved Unofficial R65 Forum V2
Technical Discussion => BMW Technical Q&A, Primarily R65 => Topic started by: JBwell on March 03, 2016, 04:28:46 PM
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Should you be able to blow air thru the front brake hose? Like you can with a fuel line? Or are there valves or something in there that keep you from doing this? This is the long rubber hose running down to the caliper. Thanks - Hope this isn't a stupid question...
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You should be able to blow air through the line. Try it in both directions. Sometimes the inner wall breaks down and creates a sort of check valve.
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If you do need to buy a new brake line
I think I have seen the specs for a new one from Spiegler somewhere but I cant remember .
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My 1981 R65 needed a new front brake hose to replace the sad OEM original. BMW parts seemed pricey for what you get.
Took the hose to a NAPA dealer that has a hose making shop. Done. Shared with me that the R65's hose fittings were the same as on Mercedes-Benz.
Still on the bike, looks very OEM and doing just fine. My R100S does have braided stainless for the twin ATE calipers.
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My 1981 R65 needed a new front brake hose to replace the sad OEM original. BMW parts seemed pricey for what you get.
Took the hose to a NAPA dealer that has a hose making shop. Done. Shared with me that the R65's hose fittings were the same as on Mercedes-Benz.
Still on the bike, looks very OEM and doing just fine. My R100S does have braided stainless for the twin ATE calipers.
Damn! That's a gem! I missed that boat.
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Thanks all - good info here. I was thinking that someone would be able to make a brake hose. I will check around in my area and see if anyone has that capability. The old girl just sat too long, fluid probably turned to shellac...
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Humm !
You're lucky !
In France it is forbidden for an hydraulic hose making shop to fabricate brake hoses.
You have to buy from an approved maker and pay the high price. Even if the hose itself is made of the same components and alike workmanship ... >:(
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Humm !
You're lucky !
In France it is forbidden for an hydraulic hose making shop to fabricate brake hoses.
You have to buy from an approved maker and pay the high price. Even if the hose itself is made of the same components and alike workmanship ... >:(
It was the same in Australia until relatively recently - for 30 years i just went to hydraulic hose makers and told them it was a hose for a bucket ram or a boat rudder trim. I'm still alive and I have never had a hydraulic hose failure.
Recently when I was rebuilding the R65 I went to do the same thing and was told that it was simply no longer a problem and anyone who had done the competency training to use the machine that swages the fittings onto the tube could make *any* hydraulic hose, including brake hose. The nice man then showed me a braided stainless steel hose that had a nitrile cover on it to conceal the braided metal (braided hoses are still illegal in Australia unless certified for brake use - which none of them are. Guess what how is on my front brake....
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Tony, can you share a little more about the brake hose replacement please?
I contacted Motobins looking for a front hose for my '83 R65 (single disk) and was told I needed two hoses, upper and lower. My bike however has a single hose, approx 750mm long, from master cylinder to lower front left fork. The final short length is steel.
Is this single hose standard on Australian market R65? I am thinking I will follow your lead and visit my local friendly hose shop and ask them to build me a replacent.
Next on the list is a replacement front disc. Short of a manhole cover can anyone tell where best to find the part in Australia?
I also plan to have a go at fixing a leaky M/C so will get a piston kit.
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My front brake lever was not returning to the forward position, thus the brake light remained on unless I pushed the lever out with my fingers. I reverse bled the system numerous times with a syringe and managed to get the lever to return to the forward position and stay there. Unfortunately this resulted in the system not creating enough pressure to close the callipers hard enough to stop the bike.
A new master cylinder and a new slave kit in the calliper housing were installed last December. The OEM brake line was full of crap at the time, so I cleaned it out and reused it. The front brake worked adequately (apart from the brake light issue), but it has always been spongy since the rebuild. Time to pull it all apart and start again! I'll be checking again for blockages in the calliper housing before I reassemble it all. It's possible that something dislodged from the inside of the brake line after I cleaned it out.
While I have it all apart this time I've decided to throw away the 31 year old OEM brake line and replace it with a brand new stainless steel braided brake line made by Pirtek (http://www.pirtek.com.au/). Hopefully I'll be picking it up tomorrow and get my front brake working properly.
The guy at Pirtek was baffled when he realised that the top connector (at the master cylinder) is metric, and the bottom connector (at the calliper) is imperial. The original fitting at the calliper end was not available in the shop catalogue, but the guy found a suitable replacement and ordered it.
The price for the new brake line from Pirtek is currently about $98.00 AUD and it is legal. I'm assuming that it'll have some kind of tag on the line which certifies that it is legal. Pirtek are indeed qualified to make brake lines. I called Enzed (http://www.enzed.com.au/) for a quote and found out that they do not make them.
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Next on the list is a replacement front disc.
If there is still enough "meat" left on the disc it may be an option to get it machined for a lot less money than buying a new one. I went that way with a Holden Monaro many years ago and saved a bucket load of cash.
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Regarding machining the front rotor, consider the wear pattern generated by the position of the rotor's drilled pattern and how much meat may need to be removed to get a level playing field.
The early pattern used by Motorrad's drilled discs creates the radial ridges common on all our classic Airheads. Depending on the wear, after the disc is machined flat, there is a strong possibility the disc will now be below minimum thickness specification for safe use.
And, yes, we've read of the missing manhole covers now rocking on some Aussie BMWs. :D
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Great info, thanks Warbucks.
I will look into minimum thickness for the disc, but it is quite deeply "rippled" due to the strange hole spacing used. I don't really understand why BMW did that, the later disks with the elongated cooling slots look a much better design.
If Pirtek are only asking around $100 i will certainly give them a try. I take it your bike also had a single hose top to bottom?
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I take it your bike also had a single hose top to bottom
Yep. It's a 1985 model; one of the last mono disc, twin shock models ever made. It has a single disc with a Brembo calliper on the left side.
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Tony, can you share a little more about the brake hose replacement please?
Next on the list is a replacement front disc. Short of a manhole cover can anyone tell where best to find the part in Australia?
I also plan to have a go at fixing a leaky M/C so will get a piston kit.
Michael my apologies for not replying much sooner, I somehow missed your post.
In regards to hoses, simply take all your hoses to your nearest Pirtek outlet and have them make up hoses for you - if they have the nitrile covered braided hose, grab it, your braking performance will thank you.
Replacement discs - with the demise of Don Wilson the only australian shop I know that is actively making disc rotors is MetalGear in Brisbane - but they are too bloody expensive at $200 and they will only exchange not send you the rotors to fit to your own hub. Next alternative is one of the various ebay sellers, I haven't looked lately but when I was looking I found prices as low as around $100 plus post for the rotor only.
Motobins were flogging Gremecia complete replacement units but no longer have them on their website - I might be worth asking.
Last alternative is get some made. a good lathe will cut cast iron accurately enough so that only minimal grinind is necessary (in fact you would probably get away with a sanding machine such as used to tizzy up the finish on heads and blocks.
Hate to tell you this but in my experience by the time a M/C starts leaking it is sleeve time - I don't know what the commercial going rate is but I am prepared to bet that having a stainless steel sleeve pressed into your master cylinder will cost a lot less than a new master cylinder will. The smart guys these days leave a good slip fit clearance on the sleeve to the M/C bore and coat everything in a thin epoxy which seals the thing in forever and overcomes the one major drawback of pressing in a sleeve which is that with the pressure in the system fluid can slowly forces its way between the sleeve and M/C bore.
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I'm assuming that it'll have some kind of tag on the line which certifies that it is legal.
The brake line is now fitted. I'm not sure what it's made from as I didn't ask. The certification is stamped on the line, and there is a clear shielding covering the entire length between the fittings. At a guess I'm assuming that the shielding makes it completely air tight.
The new line is nowhere near as bulky as the OEM line, so I might gain 0.000000000001 centimetres per second on my top speed due to the reduction in parasite drag. [smiley=laugh.gif]
My front brake has never been so good.