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1Back to top Go down   front calipers and stainless line refit Empty front calipers and stainless line refit on Fri May 03, 2019 11:33 pm

tinyspuds

tinyspuds
Silver member
Silver member
Morning all,
I have just rebuilt all three single pot non-ABS calipers to install new seals.
Although my outfit has leading links, AFAIK the front splitter is as per standard. However, PO had fitted stainless lines. I noticed when I took the calipers off that the fitting nut did not rotate on the lines and I had to rotate the caliper to unscrew it from the fitting.†
That didnít seem right and at the time I thought I would take care of it at refit but no matter what I tried I couldnít get any movement of the fitting nuts relative to the lines at either the caliper or splitter ends.

Thatís when my stupid took over. I decided that must just be the way SS lines work, put it all back together, flushed and bled the fluid during which process I had to put more than an extra half turn to the RH fitting nut to get it airtight. Naturally this has put a gentle half spiral into the brake line.
Bleeding the system was such a pain that Iím tempted to just dismount the caliper and rotate it the other way to get the spiral out of the line.

This isnít right is it?

Something should be freely rotating, yes?

The tension in the line will create a tendency to unscrew the fitting until the stress is relieved? (I used a touch of copperslip at the caliper fitting so this is relatively low friction).

Am I going to die?

Iíll take the existential feedback too, but I have cocked up havenít I?
Cheers, Stu


__________________________________________________
1985 BMW K100RT + Hedingham HUB and LLís.
2007 HD883 Sportster. Bobbed and bettered.
1954 Royal Enfield 350 Bullet. Original.
    

chris846

chris846
Life time member
Life time member
That's a 'normal' thing with aftermarket stainless lines. If you've got the type with nuts and olives, that is.
When the lines are being made up you can usually keep on tightening the nuts until things line up. If that doesn't work, it's possible to take it apart and tap the nut back up the line so's it's free, and have another go. A little bit of oil on assembly helps.

That might not be much help to you if you've got oldish fittings.

The proper solution is to design the line with swivel joints. This is more expensive (it usually involves an extra fitting) and so doesn't often get done.

Below are the Oohbay item numbers for a swivel fitting, and the M10x1.0mm adaptor that screws into the caliper port, the swivel fittings also come in 45 & 90 degree variants for where a banjo might be chosen. Alternatively (if you're replacing a banjo that is) you could use a a banjo with a M10 flare end, and screw a M10 straight swivel onto that.

370992908166†371084490251


Bear in mind that a lot of people quite correctly call against doing this sort of stuff. Manufacturers are unwilling to approve products for brake usage too. All I can say is that I've been making brake lines like this for years without a single issue. If you're not sure, don't guess.


__________________________________________________
The Longest Lunch
    

tinyspuds

tinyspuds
Silver member
Silver member
Thanks Chris,
Nice to hear that I havenít completely missed the obvs.

Currently the caliper port has a banjo:
front calipers and stainless line refit 3ab58a10

I assume that I can use one straight to replace the banjo, one swivel joint, and either another straight or re use the banjo between the swivel and line. Will solve my problem, but do you imagine I could leave the existing banjo in place, connect the locking end of the swivel and take the non-locking end nut off the swivel for direct connect to the line?
Trying to save on joints rather than costs, cos brakes is brakes; just really pleased to hear there is a solution out there somewhere, so thanks again.


__________________________________________________
1985 BMW K100RT + Hedingham HUB and LLís.
2007 HD883 Sportster. Bobbed and bettered.
1954 Royal Enfield 350 Bullet. Original.
    

Dai

Dai
Life time member
Life time member
You'll need new -3 (dash 3) series olives:

https://www.ebay.co.uk/itm/Banjo-Olives-Per-5/113713263302?hash=item1a79d6b2c6:g:iV4AAOSw02FcrNd3&frcectupt=true

IMO that price is a bloody ripoff but I couldn't find anything cheaper. I also use Dowty washers rather than copper crush washers:

https://www.ebay.co.uk/itm/Metric-Bonded-Seal-Washers-Dowty-Sealing-Washer-Sealing-Washers-M10-M24/123082283886?hash=item1ca8469b6e:m:mJmDrN6FISSUe2pmx47rK8A&frcectupt=true

They're more tolerant of re-use and of not being tightened up enough. Better still, if you find yourself in the position where you've made a brakeline with a banjo on one end and a direct fitting into the caliper on the other but there's a twist in the line when everything's tightened up, you can use two washers side by side to relieve the unwanted angle. This is heresy! Heresy, I tell you! But I've been doing it for years with never a failure yet.


__________________________________________________
'83 K100 upgraded to K100RS spec
Others...
'78 Moto Guzzi 850-T3, '79 Moto Guzzi 850-T3 California,'93 Moto Guzzi 1100ie California,
'03 Suzuki Blandit GSF600SK3 (NFS any more because wifey has claimed it)
    

tinyspuds

tinyspuds
Silver member
Silver member
Thanks Dai
Stu


__________________________________________________
1985 BMW K100RT + Hedingham HUB and LLís.
2007 HD883 Sportster. Bobbed and bettered.
1954 Royal Enfield 350 Bullet. Original.
    

Point-Seven-five

Point-Seven-five
Life time member
Life time member
I don't know what lines you have, but in the U.S. Spieglers are very common and that is what I have on my bikes.

The Spieglers come with three pieces of plastic.† Two form a clamp around the end of the line when you clamp it in a vise, and the third is a rod that fits into the banjo fitting and is used to turn the banjo in relation to the line.† They allow the user to fine tune the end of the cable to exactly the angle that's needed.†† The fact that the fitting is hard to move allows it to hold the angle you set it to.

If you have the type of ends used by Spiegler you could make the clamp by drilling a hole in a 1cm thick piece of plastic about 3cm x 6cm and then cutting the piece in half.† A piece of brass rod that is a snug fit in the banjo can be used to turn it.


__________________________________________________
Present:
1994 K75RT
1991 K100RS

Past:
1994 BMW K75S
1992 BMW K100RS
1982 Honda FT500
1979 Honda XR185
1977 Honda XL125
1974 Honda XL125
1972 OSSA Pioneer 250
1968 Kawasaki 175
    

tinyspuds

tinyspuds
Silver member
Silver member
Thanks .75
Stu


__________________________________________________
1985 BMW K100RT + Hedingham HUB and LLís.
2007 HD883 Sportster. Bobbed and bettered.
1954 Royal Enfield 350 Bullet. Original.
    

tinyspuds

tinyspuds
Silver member
Silver member
Update. Thanks all. Youíve given me enough to think about and I will rotate the caliper for now.
I suspect the braided lines pre-date the leading links (where the calipers hang from the swing arm) and even if they are not from the original teles they feel a bit skimpy in length. At some point I will either buy or make some slightly longer lines with new joints (hopefully with just a male/female swivel on each side) and do it proper. In the meantime I will keep a close watch on the banjos for loosening/leaking.†
But right now I want to ride.†
Cheers, Stu

Update. Assuming there are others out there who, like me, have only understood every other word of the foregoing hereís a really useful link that shows how itís done:

https://www.motamec.com/info/instructions_brake_hose_fittings/



Last edited by tinyspuds on Thu May 09, 2019 10:04 pm; edited 1 time in total (Reason for editing : added tutorial link)


__________________________________________________
1985 BMW K100RT + Hedingham HUB and LLís.
2007 HD883 Sportster. Bobbed and bettered.
1954 Royal Enfield 350 Bullet. Original.
    

tinyspuds

tinyspuds
Silver member
Silver member
@chris846 wrote:
The proper solution is to design the line with swivel joints. This is more expensive (it usually involves an extra fitting) and so doesn't often get done.
It seems as though PO thought washers on the banjos was a bit upmarket too.
Iíve test fitted the swivels and it looks like the extra couple of cm plus the ability to rotate the lines is enough to take the tautness out. †Iíve also tried out the straight connector in place of the caliper banjo. Tidy, but prefer the extra smidge of tyre clearance afforded by the banjos, so they will be going back on as soon as my Dowtyís arrive.


__________________________________________________
1985 BMW K100RT + Hedingham HUB and LLís.
2007 HD883 Sportster. Bobbed and bettered.
1954 Royal Enfield 350 Bullet. Original.
    

Dai

Dai
Life time member
Life time member
Oddly enough, I made two new brakelines today too, direct from the calipers to a double banjo on the master cylinder.


__________________________________________________
'83 K100 upgraded to K100RS spec
Others...
'78 Moto Guzzi 850-T3, '79 Moto Guzzi 850-T3 California,'93 Moto Guzzi 1100ie California,
'03 Suzuki Blandit GSF600SK3 (NFS any more because wifey has claimed it)
    

tinyspuds

tinyspuds
Silver member
Silver member
As I donít know yet how successful I will be at getting the old olives out without losing more length from the line, I am also considering replacing the whole run (esp as I now have fittings, dowty washers and olives coming out my ears). †
What brake line do you use? And do you think itís a worthwhile exercise for an amateur or should I just go to Venhillís Ďline builderí?


__________________________________________________
1985 BMW K100RT + Hedingham HUB and LLís.
2007 HD883 Sportster. Bobbed and bettered.
1954 Royal Enfield 350 Bullet. Original.
    

Dai

Dai
Life time member
Life time member
Ah, right. Sometime back (quite a while back) someone was selling off stock of Goodridge brake hose for £2.50 a metre. Not being one to miss a bargain, I bought ten metres of black, twenty metres of translucent and ten metres of blue (why???). I did resist the temptation to buy some Kawasaki green.

IMO the problem with Venhill's line builder is that if you get the measurements wrong, you're left with an unusable length of brake hose. At least with the do-it-from-scratch method the buggered length can be shortened and used for something else, until you cut it too short Twisted Evil

One thing I've never really seen explained in any of those videos is how to get the front lengths right. Extend the suspension to full extent (dunno what you'd do - I just stick a big block of wood under my engine), then make up one end of the hose. Screw/bolt that to the bike as if it was finished, then run the hose to the other end. I started with the calipers and worked up to the master cylinder. I put the banjo on the master cylinder and brough the hose up to the fitting point, allowing a very small amount of slack. I do mean 'small' - it wants to be just on the right side of tight because once the suspension hits the floor that slack is going to increase and you don't want floppy brake hoses.

I'm definately an amateur. I just refuse to pay for someone to do something for me if I have the time and can do it myself. Mind you, after I'd made the very first one (a rear brake hose for my Guzzi G5) I shit bricks for miles until I was sure I'd got it right!!! front calipers and stainless line refit 44271


__________________________________________________
'83 K100 upgraded to K100RS spec
Others...
'78 Moto Guzzi 850-T3, '79 Moto Guzzi 850-T3 California,'93 Moto Guzzi 1100ie California,
'03 Suzuki Blandit GSF600SK3 (NFS any more because wifey has claimed it)
    

tinyspuds

tinyspuds
Silver member
Silver member
Echo† front calipers and stainless line refit 44271†. For two reasons: I have absolutely no idea if I am competent to do the job, and b) because since posting I have ordered 2 metres of ss line and the fancy little fittings vice. See you in Snowdonia or K heaven† front calipers and stainless line refit 44271.

For anyone else interested in this stuff, leading links seem like tricky little sods as the calipers are under the swing arm with hose and bleed fittings pointed at the ground (on a trajectory that passes through the outside edge of the tyre). The swingarm rises up under braking and takes the caliper through quite an arc. My existing lines are 630mm long † and working but feel a bit skimped and limit routing options, so Iíll add 20 or 30mil using the approach you describe #fingerscrossedandbuttocksclenched emoji.


__________________________________________________
1985 BMW K100RT + Hedingham HUB and LLís.
2007 HD883 Sportster. Bobbed and bettered.
1954 Royal Enfield 350 Bullet. Original.
    

chris846

chris846
Life time member
Life time member
"You do realise that when you tell me to do s**t I just do it, right? Anyone need any swivels?††front calipers and stainless line refit 44271."

Yep, I did think of you/this thread when I went and made my brake line!
Fronts are different though. I'll see if I can post some pics of a trike leading links later on, also some ideas that might help. Hose routing is worth spending some time on otherwise you risk stretching things if you top out over a bump (done that!) or snagging passers-by with an excessively big loop of hose (not done that yet, but there's always hope). The MOT tester that I trouble with my creations is very 'practical', but brake hoses have to be spot on.

Re. length: hose is relatively cheap so guess long and just dry assemble it (no olive - just slip the hose end onto the fitting barb and see how things are looking)

Take care with flaring the braid - make sure no strands are trapped between the olive and the ptfe. If you have a dremel, the thin cutting discs make a really neat job of cutting the hose - the last thing you want is ragged braiding, it makes it difficult to get the nut on, plus it hurts like hell when it sticks in your fingers.


__________________________________________________
The Longest Lunch
    

tinyspuds

tinyspuds
Silver member
Silver member
It turned out my existing lines HAD swivels mounted up at the splitter (I didnít know what I was looking for and they were seized solid) looking forward to fitting my new stainless ones when my Gold! hose arrives from Goodridge. In the meantime I will practice cutting and olive-ing on the old lines.
As I mentioned above, Iíll use my existing line length as a minimum as I know that works and add an inch or so to give me some routing room around the forkleg/swing arm junction as thatís where I think there is a risk of chafing against bolt heads/mudguards et al. Must admit I hadnít thought of MOT complications so Iíll review examples online to make sure I donít own goal.
PS. I too have never snagged a passerby with loopy brakelines, but when I was furnishing my first flat I carried a 10í rug rolled up on my Triumph pillion seat and did a Boudica down the highstreet before I realized it was me the people on the pavement were shouting at†
(o)(o)(o)(o)


__________________________________________________
1985 BMW K100RT + Hedingham HUB and LLís.
2007 HD883 Sportster. Bobbed and bettered.
1954 Royal Enfield 350 Bullet. Original.
    

92KK 84WW Olaf

92KK 84WW Olaf
Life time member
Life time member
Yes we heard about that........
when you went kayaking.....
front calipers and stainless line refit Bbgry010


__________________________________________________
1992 K100LT 0193214 Bertha Alaska Blue 101,000 miles
1984 K100RT 0022575 Brutus Baja Red bought 36,000 now 89,150 miles
1997 K1100LT 0188024 Wotan Mystic Red 58,645 now†91,850 miles
1983 K100RS 0011175 Fricka 29,495 miles Damn K Pox
    

chris846

chris846
Life time member
Life time member
Here's one I made (much) earlier. Sadly, my welding hasn't improved over the years since.
Calipers are BMW K100 too, oddly enough.

Actually, the front shocks are BMW K100 rear as well!
front calipers and stainless line refit 00214


__________________________________________________
The Longest Lunch
    

tinyspuds

tinyspuds
Silver member
Silver member
Thanks guys. Goodridge hoses made up and tested yesterday. I left them overnight with the lever taped back to try and get those last few bubbles out but I was able to lock up the front a number of times at 15 to 20 mph and the joints held/remained dry.
By adding another 10cm to the original length I was able to get a nice gentle loop around the leading link pivot away from all the moving parts.


__________________________________________________
1985 BMW K100RT + Hedingham HUB and LLís.
2007 HD883 Sportster. Bobbed and bettered.
1954 Royal Enfield 350 Bullet. Original.
    

chris846

chris846
Life time member
Life time member
Result!
And that's your first attempt† cheers


__________________________________________________
The Longest Lunch
    

Dai

Dai
Life time member
Life time member
Pucker factor on the first ride?


__________________________________________________
'83 K100 upgraded to K100RS spec
Others...
'78 Moto Guzzi 850-T3, '79 Moto Guzzi 850-T3 California,'93 Moto Guzzi 1100ie California,
'03 Suzuki Blandit GSF600SK3 (NFS any more because wifey has claimed it)
    

tinyspuds

tinyspuds
Silver member
Silver member
I had every confidence in my two coaches† front calipers and stainless line refit 212902†.
Probably less scary on an outfit than a solo but overall I would still feel more confident if there were specs available for the tightness of the olive-d nuts. I read all the stuff about marking and counting flats and other approaches to ensuring Ďnot too tight and not too looseí but for me any metric that starts with Ďget it finger tight and then...í is never going to reassure.†
Used my instincts and guess I just got lucky, assuming that if they didnít fail yesterday or leak today then weíre probably ok.
Have to say it was a very satisfying job and at first glance I think itís better than I found it (which I canít say about everything I Ďimproveí).

front calipers and stainless line refit Ec6d9e10


__________________________________________________
1985 BMW K100RT + Hedingham HUB and LLís.
2007 HD883 Sportster. Bobbed and bettered.
1954 Royal Enfield 350 Bullet. Original.
    

moriarti

moriarti
active member
active member
My K is still on original brake lines so how much of an improvement in breaking is achieved by†
fitting the new lines


__________________________________________________
1984 k100 rs red/black VIN† 0004449
    

Point-Seven-five

Point-Seven-five
Life time member
Life time member
@moriarti wrote:My K is still on original brake lines so how much of an improvement in breaking is achieved by†
fitting the new lines
You will get an increase in stopping power per unit of lever pressure, along with a more positive feel in the lever when the sponginess of the old rubber lines is eliminated.


__________________________________________________
Present:
1994 K75RT
1991 K100RS

Past:
1994 BMW K75S
1992 BMW K100RS
1982 Honda FT500
1979 Honda XR185
1977 Honda XL125
1974 Honda XL125
1972 OSSA Pioneer 250
1968 Kawasaki 175
    

moriarti

moriarti
active member
active member
Thanks for that,another job on The Todo List study


__________________________________________________
1984 k100 rs red/black VIN† 0004449
    

25Back to top Go down   front calipers and stainless line refit Empty Re: front calipers and stainless line refit on Sat May 18, 2019 11:08 am

tinyspuds

tinyspuds
Silver member
Silver member
@moriarti wrote:My K is still on original brake lines so how much of an improvement in breaking is achieved by†
fitting the new lines
Canít say for sure on the K as I was replacing badly fitted braided. †But I would have thought that 35 years old lines were probably EOL anyway?
I have made the update to ss lines on a number of other bikes tho and they always stopped better and felt crisper. This was my first time making up my own lines and it was very rewarding and not too difficult (all the usual disclaimers apply).


__________________________________________________
1985 BMW K100RT + Hedingham HUB and LLís.
2007 HD883 Sportster. Bobbed and bettered.
1954 Royal Enfield 350 Bullet. Original.
    

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