Brake Bleeding Issues, Aftermarket MC

[gggGary]

Search Results for Query: early brake line brought up 5 pages of hits in here.
Some threads to get you started.
http://www.xs650.com/threads/early-caliper-brake-adapter-for-ss-lines.33086/

http://www.xs650.com/threads/brake-line-question-early-caliper.29323/

 

[GLJ]

Check out these guys. Their line replaced my rubber lines and my steel line.
http://www.helperformance.us/hel-brake-lines-for-yamaha-xs650-ii-1972.html

 

[TwoManyXS1Bs]

Is the spooge hole supposed to be,
- That big,
- And that far back?

 

[joebgd]

I have a stock set up on an 80, 2 flexible lines, I changed the lines to braided steel, cleaned the caliper and mc. When I put it all on I tried conventional bleeding, the hang with mc at high point for days, I had great pressure at the mc, I put my thumb over the mc opening and bled it separately, all to no avail.
Idk what is up with bleeding these front brakes but it is a fikle beast.

 

[gggGary]

I have a stock set up on an 80, 2 flexible lines, I changed the lines to braided steel, cleaned the caliper and mc. When I put it all on I tried conventional bleeding, the hang with mc at high point for days, I had great pressure at the mc, I put my thumb over the mc opening and bled it separately, all to no avail.
Idk what is up with bleeding these front brakes but it is a fikle beast.

Remove caliper, force the piston in (c-clamp), pump it out, maybe repeat, then bleed normally. Watch reservoir level so it doesn't spill over.

 

[smiles79]

Thanks for the links Gary!

It looks like the fitting that goes into the Hardline is an M12. Can anyone verify?

Also, i imagine it's external threads?

 

[650trader]

You are using what looks like a master cylinder with a 13mm. bore . The early caliper has 2
live pistons which requires something like a 22mm. bore so I doubt this set up will work
even if you can bleed it.

 

[gggGary]

Good idea but, I would NOT trust a $10.00 eBay cheapo brake line around the block, let alone any other usage. Brakes are NOT an area to go cheap on!!

I agree BUT; been using the banggood cheapo's for quite some time, on 7 or 8 bikes now, 20,000 + miles? no problems.

 

[smiles79]

You are using what looks like a master cylinder with a 13mm. bore . The early caliper has 2
live pistons which requires something like a 22mm. bore so I doubt this set up will work
even if you can bleed it.

Doesn't the stock master cylinder have a 16mm bore?

 

[gggGary]

Thanks for the links Gary!

It looks like the fitting that goes into the Hardline is an M12. Can anyone verify?

Also, i imagine it's external threads?

I see AN3 mentioned.

 

[650trader]

Still, the volume behind the live pistons is too great for what the master will move.

 

[smiles79]

I see AN3 mentioned.

So did I, but the websites I'm looking at for custom lines ask for either internal or external, and thread size. I'm not familiar with AN fittings

 

[gggGary]

Good catch 650trader! I think He'll be fine with a 13mm once he gets SS (teflon) lines, report back, Actually that kind of shows up his original problem, small diameter MC doesn't have enough volume to deal with spongy rubber lines.

 

[smiles79]

I probably didn't do enough research but I thought I saw someone using this size bore with the setup I've got.

If the stainless brake lines will help, I'm not too worried.

 

[smiles79]

I requested a quote from Spiegler, still gotta figure out what fitting I need to go into the hard line though...

 

[gggGary]

The goto page when considering master cylinder sizing. ( Support Micheal Morse!)
http://www.vintagebrake.com/mastercylinder.htm
Your 13mm should be "fine", even smaller would be better?
To be completely transparent I have reduced the MC diameter on a late model set up
but haven't used anything other than the stock MC on an early brake system.

 

[YamadudeXS650C]

To be completely transparent

Complete transparency is always refreshing.....