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Brake Line Nipple Thread

b25bsaboy

New member
With the tank emptied and on the bench, thought this would be a good time to replace the flexible rubber brake line and master cylinder. I made up a stainless steel line from a few surplus lines from a newer Triumph, but I should have realized that the male thread would have been different that what was trying to adapt.
My question is does anyone know what the TPI for the thread is on the male end coming off the solid line that fits into the female rubber line attachment that goes to the master cylinder in the picture?
 

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My question is does anyone know what the TPI for the thread is on the male end coming off the solid line that fits into the female rubber line attachment that goes to the master cylinder in the picture?

Er...this is a metric bike...you want to know the mm per thread!! :stick Often times I'll use my digital calipers to measure the distance between say 10 threads and do the math. It's hard to get it wrong...internal threads are obviously more difficult, but if you have the male side of the connection...pretty simple.

Oh, and I don't the answer to the question...sorry! :dunno

There is a discussion of bolts and thread terminology in the this thread:

http://forums.bmwmoa.org/showthread.php?t=57001
 
The most common metric brake line thread is M10x1. Here is a link which describes how to identify brake line threads. The threads have to be measured - you can't tell from a photo. One way to measure threads is to get a M10x1 bolt from the hardware store and see if it fits. Good luck!

Edit: the M10x1 bolt has a 1mm pitch thread. If you have a metric tap and die set, a tread pitch gauge should be in the set. Otherwise, it is best to use the bolt-fit technique from my experience. Link: http://www.hoseandfittingsetc.com/our-blog/bid/76568/Thread-Identification-for-Brake-Lines
 
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With the tank emptied and on the bench, thought this would be a good time to replace the flexible rubber brake line and master cylinder. I made up a stainless steel line from a few surplus lines from a newer Triumph, but I should have realized that the male thread would have been different that what was trying to adapt.
My question is does anyone know what the TPI for the thread is on the male end coming off the solid line that fits into the female rubber line attachment that goes to the master cylinder in the picture?

Thought I would follow up on my question regarding my brake line male/female threads. Over the past several years I keep hearing about Moto-Bins in the UK. Went to the web site to see if there were any custom fitted SS steel brake lines and yes they have them. Well I took the plung, place the order on line with Damien. My cost was ?ú 17.00 each plus ?ú 8.50 parcel post from the UK to Calgary, AB.

Almost ten (10) days later they arrive. First of all I get mail faster from the UK than I do at times within Canada and secondly I was taken aback to the quality of the product. I rebuilt the master cylinder and was waiting on the brake lines so that I could put the Mad Bumble Bee (R100RT) away for the winter. Pulled the old brake lines, fitted the new lines that fit perfectly and started what I sometimes hate doing is bleed the brake lines. Took a bit of pumping, then began to see liquid moving, then almost like a burp a big air bubble came out and the lever felt good, very good! Tightened up the bleed screw and this puppy has never felt this good. Think these front brakes will grab and hard......

Thank you for however told me to look at Moto-Bins.
 
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