Underslung Rear Caliper conversion on a Z1R

[Fred the Zed]

Hi

For reasons I won't go into, I'm thinking of converting the heavy, chunky, ugly caliper and disc arrangement on my Z1R to something a little slinkier looking and underslung. I understand that the torque arm mounting on the swingarm needs swapping to the underside from it's current position but don't worry, I can sort that easily enough.

I was looking at either a disc, caliper and carrier off a ZRX1100, ZXR750 or ZZR1100 for the mod. I want to keep the original wheel. Has anyone else out there done an underslung rear brake caliper conversion on a Z1R / Z1000 who can offer some advice please?

Fred

[KeithZ1R]

Think Chrisu is your man

[Z1parR]

Pigford or GB will have ideas on this too , i should think .
There's a few serial modding types about on here

[chrisu]

Think Chrisu is your man

mine is a brembo baked into the single sided hub so very off piste.

[Ginger Bear]

The Tokico caliper you are talking of was fitted to many bikes, ZX7R GSXR600/750 SRAD Early Busa's etc.

You might be able to use the complete caliper & carrier assembly, just sleeving down the spindle hole on the carrier & modding spacers to get the caliper in line with the disc.

I'm sure the disc mounting holes wont line up, so you may have to re-drill it, or make some sort of adaptor plate. or have a 'one off' disc made.

If you don't or can't use the existing carrier, it wouldn't be too hard to make a new one, from something like 10mm aluminium plate/bar.

[Fred the Zed]

Thanks for the advice guys... I'll apply my mind to what will perform / look the best.

Fred

[Ginger Bear]

Just found this pic on Ebay...... Thought it might give some inspiration.

[Fred the Zed]

Sweet

[big green bus]

Put an ap calliper and brembo master cylinder on mine and it would not hold it on a hill ! You need to make sure you get the ratio correct or you will have no brake or a one that locks with the lightest touch

[Fred the Zed]

Good point, well made!

Can you post a picture of it up for me to see? How did you sort out the hanger arrangement?

Fred

[Ginger Bear]

Fred,

I took a couple of pics of Jak's version last weekend....... Just for you!





Notice the use of small washers/shims to get the caliper central to the disc.

[Fred the Zed]

Hey Ginger Bear

That was very decent of you. It's a project that will take a little thought, but should be worthwhile in the long run.

Are Jak & Big Green Bus one and the same person?

Once again, thanks for the photos and pointers.

All the best

Fred

[hillbilly]

just to let you know,i have a brembo on my yellow beasty,its upside down,thing i found out.was that it wouldn't bleed up properly,so i had to de mount it,put it on the top of disc,then bleed it,then put back on at bottom.

[Ginger Bear]

Are Jak & Big Green Bus one and the same person?

Definitely NOT. But both 'TOP' blokes all the same.

[Big Fluff]

If you do go ahead with this conversion, you may want to think about making the caliper floating, and attaching the torque arm to the frame.
If you fasten the 'short' torque arm to the swing arm then it's straight forward enough, but as you know, when the brake is applied the rear end will dip.
In previous bikes (inc. my old Moto Martin) I turned a bush within the caliper carrier, so that when the rear wheel spindle is pinched up, the caliper and carrier bracket are free to swing 'float'. Fabricating a longer torque arm and fastening to the underside of the frame will then allow you to brake with no dipping of the rear end.
It's all down to personal preference but much prefer the feel of a floating rear brake.
Will