Topic: CB500 one piece front braided line setup. couple questions

[YogiBear]

Im planning the brake set up for the front on my CB500. Basically, I would like to use a sport bike master cylinder with the brake light switch built in, swap the wires from the OEM pressure switch to the new MC. I already have braided brake line thats the perfect length for my clip ons  However, it is the kind of line with the loops on both ends. Last night, I took the original line off and it is shot. I took the Original master cylinder off as well. Just for kicks, I tried the banjo bolt from the MC end into the top of the caliper where the hard line connects and to my surprise the threads are the same size. The banjo bolt from the MC end is a little too long. I know I saw it somewhere, but cant find it now, somebody had used the type of braided line with the loops on both ends on a SOHC 550 or 750. I guess what im asking is, is there a shorter banjo bolt I can use with my setup to utilize my braided line?

[OldSchool_IsCool]

What most people do is drill out the taper at the bottom of the caliper bolt hole and tap it through so that a standard banjo bolt fits without modification.  I think the threads are 10x1.25 but measure them to make sure.

[kslrr]

I had a SS line made with ends and adapters that threaded directly into the MC and Caliper on my CB350F.

[Kevin400F]

On my track bike, I shortened a standard banjo bolt slightly.  I think I may have also drilled away the OEM hard line seat at the bottom of the caliper hole in order to get a few more threads engaged.  I also had to slightly reduce the sealing washer diameter so it sat down into the recess on the top of the caliper.

Kevin

[YogiBear]

Thank you all for the advice and quick replys. 

[YogiBear]

On my track bike, I shortened a standard banjo bolt slightly.  I think I may have also drilled away the OEM hard line seat at the bottom of the caliper hole in order to get a few more threads engaged.  I also had to slightly reduce the sealing washer diameter so it sat down into the recess on the top of the caliper.

Kevin

This sounds like something I can do. When you say you drilled away the seat for the hard line, did you use a drill bit smaller than the threads?

[Kevin400F]

>  did you use a drill bit smaller than the threads?
>

Yes, absolutely.  I didn't touch the threads at all.  Since this particular caliper was never going to be used again in stock configuration with flared hard line, I just hogged away the little "cone" portion of old seat with whatever drill size was handy, without touching the threads. 

[YogiBear]

>  did you use a drill bit smaller than the threads?
>

Yes, absolutely.  I didn't touch the threads at all.  Since this particular caliper was never going to be used again in stock configuration with flared hard line, I just hogged away the little "cone" portion of old seat with whatever drill size was handy, without touching the threads. 

great. that sounds easy enough. I have another question, hope you dont mind. I want to cover all the bases before I start.  Ive seen threaded rod cut with a hacksaw and still have the threads usable. What did you use to cut your banjo bolt?

[OldSchool_IsCool]

If you drill out the cone, you can run a tap down the hole cutting new threads and not have to cut the bolt.

[754]

Cut the bolt, grind a new bevel cleanup the last thread with a 3 corner file..

 I dont understand the need to ruin the caliper..

 Nor, the difficulty in buying a new bolt..?

 Even easier than all that, put a spacer between bolt head and first washer...

[Kevin400F]

I cut my bolt with a hacksaw, then dressed the threads with a thread file.  My primary reason for wanting more thread engagement is that the hydraulic pressure from the line is now exposed to the full bolt diameter, rather than the very small hard line bore.   With the cone seat in place and with a flat-ended banjo bolt srewed into the caliper, you only get about 4-1/4 threads engagement before you hit the seat.  I sure didn't want the bolt to pull the threads out of the caliper under maximum braking pressure.

If you are sensitive about "ruining" the caliper, then one option could be to drill a corresponding relief in the end of the shortened banjo bolt.  This gets a few more theads, but not as much as you get by removing the seat completely, or better yet, using a bottom tap to go just a little deeper as OldSchool suggested. 

[754]

If your line has AN ends, and is long enough, use a metric to AN straight adaptor, and go straight into the line..no more banjo, sealing washer, thread depth issues, "Kid from Deliverance", etc, etc..

See pic of those style ends in post #2. That is a made up uncrimped line ( the style I used), one advantage is, you can easily shorten them..

 keep things simple... dont need no steenking banjos..