Twinpot Brake upgrade on 78 Skunk

[Eric]

Thanks- Im going with the G triple to keep the rake reasonable. Ill measure stuff up when I have parts. Pretty sure the leg ctc is narrower, but not sure if the axle mounting faces are the same width. I guess Ill find out!

[salty_monk]

When going from a 650GL to a 650G fork for dual discs, will one need to also change the axle and spacers on a GL wheel to fit the G fork? Thank you.

If you use the original triple tree then in theory the spacer pack and axle should stay the same...

In practice most are interchangeable apart from there is a different in the 35mm fork leg axle as opposed to the 37mm fork leg axle. Most of the triple trees set the forks at the same width. Anything with a 16" front wheel or a 40mm fork (GK) is different.

[topspot101]

How to replace the disk for this bike?

[Eric]

When going from a 650GL to a 650G fork for dual discs, will one need to also change the axle and spacers on a GL wheel to fit the G fork? Thank you.

[salty_monk]

I responded in your other thread. It's a specific bracket set for a particular choice of calipers & rotors on stock forks & using stock wheels. Lots of info earlier in the thread if you read through.

[S2king_customs]

Are you be able to custom any brackets for any calipers or ?

[salty_monk]

I'd love to too! Those FJ guys have a lot more room to work with between the fork legs. We're stuck with twinpot sliding pin calipers I'm afraid, opposed pistons just won't safely fit on anything other than an 1150 using stock forks & wheel.

[SameOG]

Another question:
Have you considered making and selling radial conversion brackets? I'd love to put on the Yamaha six pot radial calipers? RC51 with silver dots.
RC51 Radial Conversion.jpg

[SameOG]

I may be interested in picking up some brackets. First, I'm trying to figure out if the '83 GS550ES calipers will directly bolt on to my '81 GS750E forks. I want to upgrade to opposing piston calipers rather than the sliding/floating calipers.

Question:
Can I install other calipers with your brackets? Specifically, the Yamaha four pot blue dot calipers? FJ1100 with blue dots.
FJ1100 with blue dots.jpg

[salty_monk]

Just wanted to bump the thread to let members know that I do currently have brackets. Due to some drop off in demand over the last year or two this latest batch will likely be the last time I run these.

[salty_monk]

https://www.mikesxs.net/yamaha-xs650-76-type-single-master-cylinder-oem-366-25850-02-00-366-25850-02-00.html?utm_campaign=694122_Mikes%20XS%20Retro%20Master%20Cylinders%20July%202021%20Wk2&utm_medium=email&utm_source=Revival%20Parts&dm_i=4C4Z,EVL6,4B9557,1KE7X,1

These seem like a good option for brand new master cylinders from a trusted source. Look vintage enough for even the older Suzuki’s and are the correct bore size. $61.

I’d be interested in feedback if anyone tried one out.

[salty_monk]

Great, glad it worked out. A couple of people have welded brackets the way you have, seems like it should work ok and has for them as far as I know.

I’d definitely want a good welder as you did, would be good to know the material used originally, I was a bit worried it would “let down” the bracket and make it flex but I think it’s thick enough that you’d be ok even if it did.

[Peter#1266]

Hi Salty Monk, I have borrowed your ideas of the Honda disks and Concours calipers to uprate the front end of my GS1100GK. As you will know the GK has fatter forks and wider trees than everything else. I didnt have to shim the disks at the hub, and using the original Concours brackets with some extensions welded on (certified welder, crack tested) located the calipers spot on over the disks. Used the Concours span adjustable m/c as well. Picture over at the "what did you wrench on today" thread. Thanks for the inspiration.

[salty_monk]

Looking good! Thanks for posting up the part number of the discs / rotors

[JT1306]

Thanks!

The discs are new EBC discs (EBC MD1014X) and then just enlarged the holes to 8mm. I liked the look of the gold discs against the black wheels which I have also mirrored with the rear shocks. I've added the master cylinder off a 2010 Kawasaki ER6 so should be a pretty solid braking setup.

I'm keeping all the images stored and will provide a full build thread once I've got nearer completion, hopefully early next year.