Handlebar lighting switch

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Lifebeat
Posts: 28
Joined: Sun Jun 16, 2013 5:23 pm

Handlebar lighting switch

Post by Lifebeat »

Hello everyone!

So, I'm working up my Motobins order, with a total of around 2500$...

My bike hast these handle bar light switch with the inscriptions pretty much faded away from the sun, and on the left side, the light selector switch makes some sort of intermittent contact.

Question was, is there a nice way to restore these, or should I just spring the extra 200$ each?

Also, on the front brake handle side (1976 R75/6, under tank Master cyl), the cable adjuster doesn't have threads, and it looks like the lever housing (the female part where the cable en goes) doesn't have internal threads either? Will I be OK adjusting the brake with just the adjuster at the master cylinder?

Thanks!

Luc
chasbmw
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Location: Bath UK

Re: Handlebar lighting switch

Post by chasbmw »

As long as you have one adjuster you will be fine.

Mind you , if you want brakes that work, fit a 13mm twin throttle pull handlebar master cylinder from a much later airhead.

IMHO etc etc
Charles
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Replica 1070 R90/S (based on 82 RT)
1975 R90/6
Lifebeat
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Joined: Sun Jun 16, 2013 5:23 pm

Re: Handlebar lighting switch

Post by Lifebeat »

Ahhhhh! You've opened up the debate again!!

I was actually thinking all of this over in my head because, I'm ordering the caliper and Master cylinder rebuild kits. My premise is that if all the parts on the braking system are "new" and the swing caliper properly adjusted, it should at least give some satisfactory braking no?

If general consensus says that it doesn't, I will probably do like mentioned and put a handlebar master cylinder. BUT, if I do so, can I keep the single disk, or does it defeat the purpose? Because I would like not to have to install the dual disk kit.

Thanks
chasbmw
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Location: Bath UK

Re: Handlebar lighting switch

Post by chasbmw »

I think that the answer is that a correctly sized handlebar MC is well worth the extra money over an original under tank rebuild. It's just the ratio between the slave and master cylinder was wrong from the start. This is so even if you have adjusted the calipers well.

If you have a twin disc bike and need originality, then a single disc MC adapted to twin outlets would go some way to help

I also have a 1971 Norton fitted with a disc brake, it has exactly the same problem, but you can't get smaller master cylinders from Norton. In Norton circles the solution is to sleeve the master cylinder smaller. I just think that brake manufactureres at that date were worried that people would lock up the wheels with the fearsome new brakes.

Funnily enough this was a time when many people from the US bought bikes in the UK and Germany for a European trip, quite a few claimed to never use the front brake!
Charles
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Replica 1070 R90/S (based on 82 RT)
1975 R90/6
Duane Ausherman
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Re: Handlebar lighting switch

Post by Duane Ausherman »

That brake when rebuilt, with SS hose and perfectly adjusted will work just fine....................... if you can drag your feet.

Do the mod suggested if you want to stop.
Ask the Indians what happens when you don't control immigration.
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Airbear
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Location: Oz, lower right hand side, in a bit, just over the lumpy part.

Re: Handlebar lighting switch

Post by Airbear »

Luc, I did everything I could to make the front brake work on my '74 90/6. As Charles says, it just can't work - it's a hybrid system and the ratio is wrong. A few months ago when I was facing another refurb of the under-tank abomination I happened to read a thread on ADV where a bloke fitted an aftermarket 13mm MC - a Magura 225. The difference is frankly astonishing. I still grin every time I use this brake. It was also a lot less expensive than the rebuild kit.

Here's a link to a thread on my conversion -

viewtopic.php?f=1&t=5461&hilit=magura+13&start=10

Unfortunately, the same Magura MC will not fit as nicely (or possibly at all) on your '76 with the later controls, so you may have to go for a later model BMW MC.
Charlie
and Brunhilde - 1974 R90/6
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Graduate, Wallace and Gromit School of Engineering and Design (Pending)
Lifebeat
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Joined: Sun Jun 16, 2013 5:23 pm

Re: Handlebar lighting switch

Post by Lifebeat »

You guys crack me up! ...dragging your feet...

So you'Ve all got me seriously thinking here... The upgrade kit on Motobins goes for 475$, but I guess safety doesn't have a price... The Magura mod seems interesting, but I think I would prefer the "off the shelf" solution, even if at a premium.

A question that you guys could maybe answer, it comes with an aluminium fluid divider (the kit # is : 61170), if I only have One disc and caliper, can I just not use it and bolt the hose directly to the caliper? I'm also assuming that the hose supplied connects to the original bracket on the left fork tube right?

OH! And BTW, any insight on the light switch issue?

Thanks a bunch!
khittner1
Posts: 508
Joined: Thu Oct 04, 2012 8:46 am

Re: Handlebar lighting switch

Post by khittner1 »

Geez, I guess I didn't realize how inadequate the front brakes were on my 90Ses and R90/6. They may've been an early variety of ABS system, but they could stop the bike from normal highway speeds without too much death-gripping.

There's no good way to rebuild /6 and /7 handlebar switches. If they won't do what they're supposed to after a few squirts of electrical contact cleaner, it's replacement time.
Duane Ausherman
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Re: Handlebar lighting switch

Post by Duane Ausherman »

The /5 drum brake was far better than the single disc. The official stopping distance required notice by the USA government even showed that it was not as good as the /5.

In the first week of our first /6 we knew that something was wrong. One can go to the double disc such as on the R90S, but then you have a super heavy fork that doesn't handle well.

Get the good stuff and forget it.
Ask the Indians what happens when you don't control immigration.
Roy Gavin
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Location: Adelaide Australia

Re: Handlebar lighting switch

Post by Roy Gavin »

Back to the OP question re switches, I would stick with what you have.

I replaced my old, tired switchgear on my G/S as I figured after 350,000 km and over 30 years I was going to have to sometime, and I may as well do it when it suited me.

However, neither the LH or the ignition switch have lasted 20,000 km, and the old stuff is back on.

Regarding the ATE brakes, I saw somewhere that you can now get HH pads for the swing callipers, and they will make a big difference, if you can find them.

When it comes to aligning the pads, the original instructions were just to apply the brake as hard as you could, and this would line the pads up. To do this needs a fair bit work to get the calliper and pin moving freely, but IMHO your brake will never work properly unless it does.
Adelaide, Oz. 77 R75/7. 86 R80 G/S PD, 93 R100 GS, 70 BSA B44 VS ,BMW F650 Classic
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