Having trouble with salty_monk brake upgrade

[MadCapsule]

I've got everything mounted up and I'm having interference issues. In order to get the caliper over the rotor, I have to compress the pistons to the point that the outer brake pad doesn't clear the retaining clip. When I squeeze the brake lever the retaining clip scrapes against the rotor instead of the brake pad.

Here's a close-up pic and further details: https://imgur.com/j20vffV

A few pics of the mounting points: https://imgur.com/a/FxkMG

These are the brake rotors I bought: http://m.ebay.com/itm/95-96-97-98-HONDA-CBR-600-F3-FRONT-BRAKE-ROTORS-pads-/321961680732?txnId=1579864856011

Any thoughts on what I might be doing wrong would be much appreciated. Also, I can take more pictures if needed.

 

[Dogma]

I wish I was expert enough on that installation to help. I just put the spacers behind the rotors and everything bolted up.

 

[steve murdoch]

What calipers are you using?

 

[MadCapsule]

Thanks anyway, Dogma.

Here's a pic of the whole set up, in case there's anything glaringly wrong that I didn't catch: https://imgur.com/Z1BZbq3

 

[MadCapsule]

What calipers are you using?

One is from a 1988-1996 Ninja ZX-600 and the other is from an '88-'07 Ninja 250.

 

[Guest]

Dumb question - you do have the spacers between the wheel and the rotor carrier?


Mark

 

[MadCapsule]

Dumb question - you do have the spacers between the wheel and the rotor carrier?


Mark

Yes. It almost looks like it would work without the spacers, but I can tell that the rotors would ultimately be too far inboard.

 

[tkent02]

Is it the same on both sides, both calipers, or is one too far inboard and the other too far outboard?

Wheel bearings installed wrong will put the wheel off to one side.

 

[MadCapsule]

Is it the same on both sides, both calipers, or is one too far inboard and the other too far outboard?

Wheel bearings installed wrong will put the wheel off to one side.

It's the same on both sides.

 

[MadCapsule]

I'm wondering if the rotors I got were mislabeled and aren't actually from a CBR 600 F3.

Does anyone know what the offset for the rotors is supposed to be?

 

[steve murdoch]

F3 offset is 17.0mm
F4/VFR800 offset is 17.5mm

www.metalgear.com.au is a great site to check for rotor/brake pads spec.

 

[salty_monk]

17mm is about right and there is usually enough play that a mm or so either way doesn't matter.
This is the 750 but with an 1100 front fork?

if those rotors are 295mm (which they look to be) then they are the F3 ones with 11 rivets between carrier and brake surface.

what triple tree are you using? Is that the 750 wheel?

So im understanding correctly you need LESS offset right?

I have some odd thinner spacers so we can make it work one way or another - don't panic

 

[salty_monk]

From the pics it looks like you need more rotor offset not less. How much distance do you have between the brake surface and the fork leg?

 

[MadCapsule]

17mm is about right and there is usually enough play that a mm or so either way doesn't matter.
This is the 750 but with an 1100 front fork?

if those rotors are 295mm (which they look to be) then they are the F3 ones with 11 rivets between carrier and brake surface.

what triple tree are you using? Is that the 750 wheel?

So im understanding correctly you need LESS offset right?

I have some odd thinner spacers so we can make it work one way or another - don't panic

Let's see... Forks are from an '82 GS750E.

Rotors have ten rivets.

Triple tree is stock, aside from replacing the 1977 model year top clamp with one from a '79 when I had to replace the ignition switch. '77 top clamps don't have provision for a replacement ignition switch, as it is molded into the gauge cluster.

As far as I know, the wheel is stock 750 (19"). I certainly haven't replaced it.

I need more room between the braking surface of the rotor and the fork leg.

 

[MadCapsule]

From the pics it looks like you need more rotor offset not less. How much distance do you have between the brake surface and the fork leg?

There appears to be about 4.75mm between the braking surface of the rotors and the fork legs.

 

[salty_monk]

So the new fork legs are also 35mm and you are using the stock triple tree?

My best guess is that the donor bike triple trees would be wider than the single rotor model. Ordinarily you'd have about 9mm between braking surface and fork leg.

If you remove the spacer behind the rotor to give you the 9mm what happens? Does the caliper then interfere with the wheel spokes? Is the caliper center offset to the rotor braking surface center (viewed from the top) at that point?

When you use the GS550 rotors instead of the CBR the offset is a little bit off center but it doesn't seem to matter at all (other than making it more difficult to fit the calipers).

The measurement you need is what offset will center the braking surface in the middle of the caliper. We then just have to check for caliper to wheel spoke clearance as if you have bolt to rotor clearance now then that will only grow not shrink.

if you need thinner rotor spacers I can swap yours over. I have a couple of odd sets of thinner ones that should work.

Also just humor me and check rotor dia is 295mm just in case.

 

[MadCapsule]

So the new fork legs are also 35mm and you are using the stock triple tree?

My best guess is that the donor bike triple trees would be wider than the single rotor model. Ordinarily you'd have about 9mm between braking surface and fork leg.

If you remove the spacer behind the rotor to give you the 9mm what happens? Does the caliper then interfere with the wheel spokes? Is the caliper center offset to the rotor braking surface center (viewed from the top) at that point?

When you use the GS550 rotors instead of the CBR the offset is a little bit off center but it doesn't seem to matter at all (other than making it more difficult to fit the calipers).

The measurement you need is what offset will center the braking surface in the middle of the caliper. We then just have to check for caliper to wheel spoke clearance as if you have bolt to rotor clearance now then that will only grow not shrink.

if you need thinner rotor spacers I can swap yours over. I have a couple of odd sets of thinner ones that should work.

Also just humor me and check rotor dia is 295mm just in case.

Yep. The new fork legs are 35mm and the triple tree is stock, as far as I know. The lower triple was on the bike when I bought it. The top triple is from a '78-'79 750, to accommodate a new ignition switch.

I'll check the clearance without the spacers behind the CBR rotors and with the Suzuki rotors when I get home and get back to you on those. (I have two single-disc rotors from a 750, which are the same size as 550 rotors, correct?)

I'll also confirm that the CBR rotors are 295mm.

 

[MadCapsule]

OK, the CBR rotors are indeed 295mm (11 5/8").

I'm putting them back on without the spacers right now.

 

[salty_monk]

Ok good! Let me know what the results are!

 

[MadCapsule]

Strangest thing. It all seems to line up without the spacers on. There was some extra room between the fork leg and the caliper hanger as well as between the lower bracket hole and the spacer, but I took up the slack with a washer for each and it's fine.

There's now plenty of outer brake pad visible above the retaining clip.

I just need to cut a few threads into half of the rotor bolts. Six of them have the Suzuki S on the head, six do not. The six without the S have a shoulder that is slightly too tall and it butts up against the threads in the hub. Wasn't an issue with the rotor spacers installed.