Topic: Some help needed with brake/clutch lever assemblies-

[Hannibal Smith]

This is the front end I am currently building at my shop (top clamp/lower clamp/steerer/nuts etc.) and I run into a little snag with the clip-ons.

The factory brake master cylinder/lever assembly for the 1974 CB550 racer I am putting together is too long- From the perch clamp to the banjo, I am getting a span of 4.6 inches- with some machining, I can close this gap by 1/2" but it is still to long of a span (the banjo hits the clip-on clamp assembly) and with the throttle, the bars would have to run way too wide, I am keeping this build "skinny"-

Anyway, does anyone have or know a source for a somewhat period correct (80's would work) brake master that has either a remote reservoir or is just "shorter"? Called some salvage yards, and without an exact part number, it is beyond these cats/catettes to look around.

[Hannibal Smith]

What is a correct vintage setup for your 750 racers of the 70's?

I really also need the cable clutch assembly too that will match.

No electrics on the clutch lever assembly, unless the racers ran a gutted hi/lo/turn box?

Any pics?

[bwaller]

You can use a Nissin master with the banjo connection in the front, around 3.75" from perch to resevoir, cheap on ebay. A 1985 VF500F (Interceptor) was the same.

I got a clutch perch from an R6 that works with a Honda cable.

[turboguzzi]

like Bwaller, for clutch side, Any R1/R6 lever assy will be good, look racy and not so out of period.

Nice work you've done, love your triple clamps!, but seeing the bar tube clamp, no wonder you've run into trouble with the MC,

I can tell you right away that a separate reservoir MC is not going to solve your problem.

the bit that is near to the bar tube is the piston body and I dont think that you'll find any with it much shorter or further away. The only solution that you'll find would be a modern, "radial MC" where the piston is 90 degs to the bar. problem is that if you race vintage, it might not be according to the rules.  check the rules book.   

[bucky katt]

i ran a nissin from a watercooled beemer when i had clip-ons.......still do in fact. it did the trick and has a neat remote resevoir

[Hannibal Smith]

Thanks, guys- I might have the issue licked, I have a Nissin unit sourced from a Triumph inbound with a front banjo and 3.5" (approx) span, the guy even has the matching clutch lever assembly, from the pics, it shouldn't look too out of place, it has a built in reservoir, and the levers are simple without any adjustment dials/cams etc. With the push/pull assembly, I should be able to keep the bar width minimal.

When I was making the front end, I tried to keep all the design/machining plausible for 1970's.  
 


Made the steerer and nut from 17-4 and the nut is 26mm just like the rear axle for tool commonality, and clamps/clip-ons are removeable/adjustable with the same allen key. Clip-on main clamps have the pinch bolt rearward and outboard, makes adjustment a snap, especially if the bike is fully faired.

[Old Scrambler]

Suggestion............install a stud on the lower tree for a period-correct steering stabilzer on the right side.  The other end could mount to the frame or the motor.

[turboguzzi]

very nice.

what's the weight of the parts?

would you produce more sets? if yes, at what price?

TG

[voxonda]

TG,

If this effort fails, PM or mail me, think I can help too.

Rob

[Hannibal Smith]

I will do a weight comparison once I pull the assembly apart (doing the dry-build right now), it is lighter than stock (just by feel) but the stock triple is actually not too bad weight wise, I was expecting it to be way heavier. The stock steerer is actually very light, and sans a titanium unit, is race ready weight wise IMO. The lower clamp is where I actually shaved some grams here, it isn't radically lighter, but my clamping surface is 1.8" long and mega stiff, when I pull the top clamp with the bike loaded on the front wheel, the tubes stay nice and parallel with the steerer, and the top clamp just slides back on.

The top clamp is lighter, but not by a huge margin either. I have made units from ZK-60 Magnesium, but diminishing returns was the order of the day with that material. No matter what the figures say about particular Magnesium alloys (PSI-tensile etc.) the nature of it requires that you got to meat it up, to the point where even 6061-T6 ends up beating it, because you can make much thinner wall/webs etc. Long story short, Magnesium is fantastic for wheels and covers, but for clamps is not so great IMO.

As to producing this stuff, I am overloaded as it is with what I produce normally, this is just one-off stuff for stress relief.

[Hannibal Smith]

There is something very satisfying about precision fit, the tubes will "hiss" when you slide them a perfectly bored hole!



Important dimensional info-

Fork tube spacing (factory) is 182mm NOT 180mm as seen on the internet typically.
Factory offset is 45mm

Factory tubes are 1.374" and the tubes on this build were supplied by "Forking by Frank" and were also 1.374". If you punch your clamps to 35mm, they will work but will be sloppy.

[turboguzzi]

Never sat down to calculate weights but was hoping that an ally lower clamp and steerer tube would yeld 300-400 grams advantage compared to the stock iron pieces, alas that might not be the case.

I cant think there can be any gains on the stock ally top clamp though.

Thanks for the tip on the diameter.

Hope you found a solution to your MC, but in case you didnt, look at these clipons form gilles tooling, very smart design, would be easy for you to replicate (they dont do 35's anyway...)

http://www.gillestooling.com/en/produkte/gp/index.php?foto=1

Tg

[Hannibal Smith]

I really didn't sweat the weight issue, I have had to in the past on modern racers, but the factories have kept pace, it takes big bucks and time to shave a few grams.

It's definitely lighter than stock, but not one of those "wow!" weight savers. Compared to Marchesinis and the like, no amount of titanium or mag on the bike can offset those spoked wheels or the frame etc.

I just did it to be different.

Forgot to add, the pics of the clip-ons are deceptive, they are VERY light. I punched them at 5 degrees, I usually do 7-9, but I wanted to minimize the height of the clamp assembly, and it is easier on the wrists when you are about to turn 40....

[mad mike]

hi hanibal,  ref. your problem mounting your master cylinder,have you considered extending the handlebar section through the billet clamp and mounting the m/cylinder inboard,[also doing the same for the clutch side], this would still enable you to keep the narrow profile you require,  i used this setupon my old norton racer many years ago,  i have a master cylinder off a cb750f2 [twin disk] if you need it.    regards,     mike.

[Hannibal Smith]

hi hanibal,  ref. your problem mounting your master cylinder,have you considered extending the handlebar section through the billet clamp and mounting the m/cylinder inboard,[also doing the same for the clutch side], this would still enable you to keep the narrow profile you require,  i used this setupon my old norton racer many years ago,  i have a master cylinder off a cb750f2 [twin disk] if you need it.    regards,     mike.

Holy Smokes! That solution completely escaped me! Once I get the setup, if it's still too long, I will definitely run the stuff inboard past the clamp. Thanks!

[turboguzzi]

The Moto Guzzi Le-Mans have that solution, I happen to own one....

It will make the overall handlebar span/width much smaller though.

Sure worth giving it a try.

TG

[turboguzzi]

Hannibal, Rob

Just back form the garage:

I am running Cagiva Freccia C9 125 triple clamps om my racer (-15mm offset compared to stock) and the weight of the top ally clamp is 550 grams (1.2lb.) while the bottom steel clamp + welded steerer tube is 1250 gr. (2.75 lbs).

how does that compare to your milled ally setups?

TG   

[754]

Hannibal, nice parts.. what country are you in?

  re 750 Honda mc from sohc;
you can shorten the end,

you can run 45 degree an fitting, rather than banjo

you can shorten the end, plug, then make new outlet 90 degrees to the bore

you might be able to move the MC outward at the clamp area (with small adaptor)and gain, needed clearance..

 re clipons;

you can thread in your bars, more clearance.
 
you can fasten the bar into clamp, with 2 fasteners on the fork side of  the bar, either camlocks or allen head... in fact the outer edge of the bar could be in the open, using 2 fasteners inboard and a slit.

 ....................................................................................

Be careful with aftermarket fork tubes I have run into 1 or 2 though over, or more.. on seawbgs forks, I had to hob=ne the lower legs to fit the fork tubes, while they slid into a stock leg with wear that I had..
.................................................................................

 Re extending the bar  past the tee, are you guys saying the clamp portion of the MC is past the bar mount towards the center of the tree?

[Hannibal Smith]

UPDATE- The Nissin lever assemblies with the forward banjo etc. just came in, and just exactly fit!

I set the fantasy perfect setup, then starting installing the MC and push/pull throttle, and it fits with a millimeter to spare. Lucky shot.

Thanks for the input, fellas-

I live in Santa Barbara, California- to answer 754

[DaveBarbier]

UPDATE- The Nissin lever assemblies with the forward banjo etc. just came in, and just exactly fit!

I set the fantasy perfect setup, then starting installing the MC and push/pull throttle, and it fits with a millimeter to spare. Lucky shot.

Thanks for the input, fellas-

I live in Santa Barbara, California- to answer 754

Hey Hannibal, this is an old thread but any way you could post pics of the Nissin MC you're using? I have a '78 550 and have the same problem.
If you can see it I added a temp. small spacer to see what kind of clearance I'd need. I'm thinking instead of getting an MC that's shorter, I'd get one that's more "out" if you know what I mean to mimic my setup. But a link to the MC you bought would be appreciated.

Thanks!


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1978 Honda CB550K

[754]

See reply 17.....

[DaveBarbier]

See reply 17.....

Thanks 754, but this doesn't seem to help me. Are you sure you mean 17?

["I am running Cagiva Freccia C9 125 triple clamps om my racer (-15mm offset compared to stock) and the weight of the top ally clamp is 550 grams (1.2lb.) while the bottom steel clamp + welded steerer tube is 1250 gr. (2.75 lbs).

how does that compare to your milled ally setups?"]

I looked around this thread and couldn't find a picture or a link to the MC he's using. I'd love to get some measurement specs of it too, but that might be asking too much. I just fear the clip ons I got are too big on the handlebar clamp side for the Nissin MCs.


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1978 Honda CB550K

[754]

Dave looks like yours can move over an inch to left. And you only have the one instrument there, can you not move it a bit?

[DaveBarbier]

Dave looks like yours can move over an inch to left. And you only have the one instrument there, can you not move it a bit?

It definitely can move over to the left a little but that's because I modified this. I made a small spacer to go in the MC clamp so it juts forward (I mean forward as in perpendicularly to the handlebar. Like towards the front wheel not forward as in left towards the gauges.) to clear the handlebar clamp on the clipon. The only thing preventing the stock MC to fit well is the clipon handlebars. Nothing else is in the way.

In my picture you can see the bright glare coming from the aluminum spacer right by the ignition switch. I just think this isn't terribly safe although it's pretty rock solid. I just want to know if the Nissin MCs will be able to clear my clipon clamps. Or maybe someone knows of a different MC. I'm asking because I need to rebuild my MC and am just thinking of getting an aftermarket remote reservoir one so I know it's safe and so my reservoir isn't cocked. (I think that's a common problem that people run into when they add clubmans or clipon bars.)

Thanks 754 for bearing with me. I think I'm not very good at explaining this kind of thing, haha.


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1978 Honda CB550K