Honda CB750 Sandcast

Reproduction Straight Fitting Front Brake Hose

Wayne · 22 · 8444

Wayne

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I'm heading out tomorrow (April 19th) to see a guy that does hydraulics, brake hoses and such. He's going to have a look at my straight fitting front brake hose from 576 and see what he can do to duplicate it. He needs to see the hose/finish to evaluate it. Steve Swan has sent me an early lower line so we can see the finish as mine is badly rusted. I'm assuming mine would be the same finish, upper and lower, only with smooth crimps. I see light machine marks on Steve's banjo fitting. Also, I see the line does come out of the banjo fitting at a slight angle on my line. Is mine bent or is that correct? Any thoughts, tips or suggestions before I head out in the AM would be appreciated. Thanks!

Almost forgot, the line must meet DOT or he can't make it. I think that probably means some type of marking on the rubber hose.
« Last Edit: April 18, 2010, 11:29:07 am by Wayne »
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Steve Swan

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Of course, Wayne, the hose i sent you is a lower hose.  I am trusting you have an upper hose as an example, the upper hose banjo fittings same as banjo on lower hose.


Wayne

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Yep, have my upper hose to take as an example along with your lower Steve. Just thought someone may have input on how shiny finish should be or things like that. If he can make them I want it as close as possible to the original look. Were the machine marks (lines) inherit to all of the fittings?
« Last Edit: April 18, 2010, 07:41:33 pm by Wayne »
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Wayne

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As I suspected DOT regulations get in the way of making an exact duplicate. (legally) I did have them make me a line and the fittings look pretty good, have the machining marks in them so that part looks pretty authentic. The bend in the lower fitting is slightly longer than the original. The problem lies in the crimp, and the line itself. To meet DOT the crimp has a number at each fold if you want to call it that, and the line itself has the SAE spec on it. As we know the crimp on the original line is smooth and there appears to be no SAE markings on the line.  :(

I bought a couple of extra banjo fittings and some line with an idea in mind. If I were to take an image of the original crimp and load it into CAD we could probably cut a 2 piece die on a CNC machine. Using that die in a press we could crimp the banjo and hopefully come pretty close to the original crimp. The curve in the lower fitting will still be slighty longer (although hidden) and we would still have the SAE markings on the line. (unless we can find unmarked line which I doubt, unless one of my old co-workers can cuddle up to a supplier for me)

Of course these lines if they were made would not meet any DOT spec. At worst I have a line for my bike albeit with the wrong crimp. If anyone has any other ideas or suggestions, fire away. I'm not even so sure my idea is plausable or that the outcome would be worth the effort.

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Steve Swan

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Wayne, the new brake line looks great !

Of course, the early banjo's are short neck.  And, as far as i can tell, the banjo's were steel with zinc plate over the steel.

Wayne, you have a set of short neck early lines to use as a pattern to model the new lines by.  I like your idea of making up a die to duplicate the markings on the banjo.  I will look more closely at the lines on 232, not sure what machine markings you are referring to, but no doubt they are there, i just have not looked closely for them.  The lower line i sent you is from 2157 and the upper line from 2157 apeared same as the upper line that came with 232.  My casual examination revealed no differences between 2157 and 232 lines, but it owuld be good to have Chris weigh in here as well as Mark Buettner.

If you can get the banjos to have a short neck and the markings close or even the same, i would buy 2 sets.  I think it is worth the endeavour, there has to be a number of guys out there who need these early short neck lines.


Wayne

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Steve
The finish on the banjos I have look very close to the sample you provided. The machine marks I'm referring to are around the perimeter of the banjo. They are grooves you can feel if you run your fingernail over them. You can see in the picture that the banjo neck, or crimp area is slightly longer than original. I don't see why I can't machine a bit off there to make it exact. If the die works out to crimp the upper I think we would have a perfect match on the upper fitting. As for the lower, like I said the curved portion is roughly 3/16" longer. With the bike together I think one would have to really get in there to see that.

When they put my line together they did question whether my upper fitting is bent or should it be dead straight. I'm still not sure. Either way, we can put the bend in if necessary. (attached pic shows slight bend in fitting)

Once the feedback is in I'll head over to the Machine Shop and see when I can get some CAD/CNC time!  :)
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Wayne

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Wayne, i am not aware there is any bend on the short neck early brake lines.  The necks are straight and short.  steve

Thanks Steve
Mine must have been damaged at some point in it's life. So, the banjo I procured is very close! All I need to do is to come up with a crimp process that matches the original, shorten the crimp area to the same as original and we should have a very correct looking upper banjo. Do you think the slightly longer curved neck in the lower fitting is a big deal? Also, if there were no markings on the original lines I would like to try and find some that has not yet passed by the ink process. That might be easier said than done.

Just out of curiosity. What are members using for lines on their current restorations? Steve, as soon as I get a sample completed that I am happy with, I will send it to you.
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vnz00

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Hi Guys, is it just me or is the new fitting a little too long?

The lines I pulled off my #1853 had the short banjo's all the way through.  So there are 2 short neck banjos on the upper, one short neck and one female end for the lower.
There is writing on the lines too - Im not sure what mine says, but looks to be in yellow.  You can just make it out in photo 3.
For what it is worth, I dont think people would be too worried about if there was writing on the lines or not, or even if the crimps werent 100% perfect.  Of course, if feasible and possible go for the most original line possible but the main feature people are looking at is the short banjo, its finish, and if they are road legal.

I think the crimping on the new hose is pretty spot on anyway - if you have a look at Steve's short neck, there is not one long row of crimps, but rather 2 small, almost square looking rows of crimps, very slightly staggered.  And I dont think these crimps are done by a 2 part die - I dont think it is possible.  It looks like they were pressed radially, rather than in a 2 part die.

But I think there would be a market for them, maybe a kit with the chrome banjo bolts as well?

For restorations, I have seen people using the black banjoe new lines from honda, but I replaced the ones on my sandcast with the 'period correct' zinc plated banjo hoses which replaced the short neck ones.

Good luck Wayne.   I was just talking to KP about this 2 weeks ago.  Im glad someone is running with it.

Regards, Steven.


Wayne

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Steven
Thanks for your feedback. I just looked at the lower(s) on 567. I have a dealer installed dual disk. My left (original) has short neck banjos like yours. I do not see any markings on the hose itself. My right line (dealer add on) has a longer banjo. No markings on hose.

When I first got the bike and took pictures, I believe it was Steve Swan that said I had an early straight banjo at the master cyl. so I only assumed it was correct for my bike and that's what I set out to duplicate. ooops! I just reviewed his posts in this thread and he did say "Of course, the early banjo's are short neck". If that's the case and early lines look like yours Steven I'll have to do some more digging. If mine is indeed an early "straight fitting" line I'll carry on.

I spoke with my friend who does a lot of work like this and he says making a die to replicate my crimp (if that's what we indeed need) can be done "without a stupid effort". So as I suspected no big deal to transfer the crimp into CAD and cut the dies on a CNC. He says we may get a parting bit of a parting line when we press it. We won't know until we test one. If we do, I say machine it out and re-zinc the banjo. Once these lines are assembled I can pressure test them but they will NOT be DOT approved as DOT lines now have a very specific crimp and markings. They would be for restoration/show purposes only.

OK, lets say my line is wrong and we need all short neck like Steve's. Perhaps a couple of ways to go at this. There is patented process called a "lifesaver" process for decent fittings. They will take the original banjo apart, braze a new sleeve on and then you can get it finished to your liking. (zinc in our case) Once that is complete they will crimp the refurbished banjos onto a new line. The crimp is DOT approved and will be marked at each fold with a * - 1 - 2 - 3 - 4 etc. (see pic)

I'm guessing we could also take apart a new banjo, have it modified to look like the original and have that crimped to a new line. In both scenarios the line has all current DOT markings unless I can find someone who will give me some unmarked or who might duplicate the original markings for me. (unlikely) The line is marked in white with "DOT - GY - 10/09 - 1/8 HL".

So, having said all that, if my line is NOT an early "straight" banjo I'll have to get my hands on one to get the ball rolling. Perhaps someone has one and would like to try the "lifesaver" process? From that we can try and make a clone and see how it works out.

Again, what have folks been using up to this point on their restorations? Just curious.
« Last Edit: April 21, 2010, 04:48:40 pm by Wayne »
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Steve Swan

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Hi Wayne,

The top STRAIGHT SHORT NECK EARLY line is SAME neck/banjo as the short neck on the lower line i sent you.

DOES YOUR UPPER LINE ON YOUR BIKE HAVE A SHORT NECK ?

As you note, your RH caliper should have the later long neck line, as fitted some point in time after the bike left the factory and landed in retail hands.

Unless your lines were replaced, your upper line should be the early short neck type, same for the lower LH line.  Also, your hose junction that bolts to lower triple clamp should not have the hose locating fork in it.

To my knowledge, NO SHORT NECK LINES, UPPER OR LOWER, HAD A BEND IN THE NECK.  ALL SHORT NECK LINES WERE STRAIGHT.

Those GUYS who do not have early short straight neck lines are using the later long neck WITH bend.

I am abssolutely certain, if you can replicate the early straight short neck lines, you will sell them.  All one needs to determine a potential demand is look in the VIN Directory for the number of pre-long neck vin bikes.  Am certain many of these vins, the lines have degraded or even perished.


Steve Swan

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oops, WOW, just noticed GREAT pics from Steven of early upper/lower lines and junction connector 'box'.

Wayne, i agree completely w/ Steven.  As long as the hose is the same (no ink stampings necessary) and the banjos are close to same as original, they will be an "in demand" item.  I would say the little square crimp marks would be vital to reproduce and the top row of other markings would be good to have also.  Whenever possible, reproduction parts should be as an exact copy as possible.  Absence of any ink stampings is easily forgiveable, not sure new lines ever had those.  Certainly the later K1 type had them as do the new current prodcution lines, but i am hazarding to guess the early short neck hoses had not ink stampings......


Wayne

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Thanks for setting me straight Steve. My upper line is the one I posted earlier. It has a long straight neck with a smooth crimp. My lower right also has long necks and the smooth crimp. The lower left has short neck the same as Steve posted.

When I look at the crimps on the original hoses vs what current DOT requires there are some differences, the main being the character/numbering system around the crimp. (see photo) The crimp itself is pretty close. So, the first question is, can we live with that? (again, see photo DOT crimp)

If not, and I have a tool made to match the original crimp the line will not be DOT approved. Ditto if I procure flex hose with no marking. I can pressure and leak test it, I can even take it to the failure point but it won't be DOT.

The text shown on Steve's line would be very difficult to duplicate. I'm not saying it couldn't be done but it would go far beyond the cost of making just a tool to duplicate the original crimp. If we decide we want to go with the original crimp, non DOT banjo I'll see what my friend thinks. He's a genius at this stuff and does a lot of tooling/fabrication etc. for our military base here in town.

So let's start there...now that I'm clear on what an early line looks like. I apologize for the confusion. Whichever way we decide to go I'll need an upper line so we can make it the exact length. That will show me the brand markings as well.

If we can get one made up that does the trick the rest will be easy. I'm not looking to make any money. I need lines like everyone else and I'm more than happy to send them out for the cost plus shipping.  :)
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vnz00

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Hi Wayne, if it helps with DOT approval, why not use the DOT lines with the markings on it, and then take the writing off prior to sale, or give advice on how to once you sell it.  Im sure a bit of elbow grease and the right product will take that writing off.  No need to duplicate the existing stuff on my lines, but give the buyer the choice of whether it is removed or not.  They may decide to put it on a rider which means the lines will be on a registered vehicle.

Im not sure how it goes with legalities in the states.  But if you have to resort to ebay to sell the lines, there may be issues with publicly selling non-DOT lines.

Im pretty sure you will need to refabricate the short neck banjos, in which case if they are not DOT approved (Im not sure what that entails) a non-marked non-DOT approved line would not be a killer.

BTW, if you need to check what an early brake hose junction looks like, have a look at my photos.  There is no casting to hold the junction in place like the later ones.

Regards, Steven.


Steve Swan

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i would say the most important features are in this numeric order:

1.  short straight neck
2.  square crimp mark
3.  lettering text/numbers around crimp
4.  the hose should be the same, ink stamp not that important

again, lettering/numbers would be frosting on the cake, but not nearly as important as short neck, square crimp marks.  would think the long neck banjops could be cut down to short necks, easy enough.  The bigger deal is making tooling to replicate the crimp type.