z650 Cafe Racer Update 2022

I decided to get stuck into this project again, I really want a cafe racer on the road and to achieve that, I need to do some fabrication and source lots of parts. The bonus is that I can have some pictures for my next book (more on that below).

The major areas needing some degree of fabrication work are:

  • The frame
  • Swingram
  • Front Brakes
  • Engine (Minor Work).
  • Exhaust System.

Frame

The frame needs some work to finish the loop so its correctly welded in and it matches up with the seat positioning. I dont yet have the seat base so I will not be doing any modification till I get it.

I also still need to de-tag a lot of the factory brackets and make a spot for the battery to sit. I also need to provision space for the electrical system and the exhaust pipe mount brackets under the seat. I’ve made progress on all of these so now I need to finish the frame! I will cover the frame progress in future posts.

Front End

The z650B1 has 36mm forks, this limits the available parts as there is not much available for 36mm tube diameter but all I really need is a set of headlight brackets until I fabricate some myself later. I also need a top triple clamp to custom mount the instrument cluster.

The forks I currently have, have been hard chromed so are the original factory ones and the lowers are powder coated in Satin Black. I purchased new custom alloy caps to screw the fork springs down with and have seals and dust boots. Prior to renovating the forks, I used them to make this post: https://sidyoung.com/replacing-fork-seals/

While putting everything back together, I’ve managed to miss-place a circlip!
I temporarily miss-placed the circlip that sits in the grove shown above, however I’ve now located it!

With all the bits on hand, the forks look like being the first assembly to go back together.

Front Brakes

The old z650 caliper is pretty bulky and not great at stopping the bike, so I will be putting a GPz900R caliper and master cylinder on it as well as some HEL brake lines. I have done this on my ELR Clone and it works incredibly well. I just need to sort the spacing and mount the caliper using the factory z650 disk.

Once the forks are assembled and installed in the triple clamp, I have a front guard from a zx10 which should fit between the forks. I will need to fabricate a pair of “L” shaped brackets to mount it to the lower fork legs.

Engine

The engine looks like its still in factory original form but with extensive neglect. I will need to strip it, Water Blast the alloy, paint it and put a new gasket kit through it at the minimum.

he internal state was not known but I did take out the clutch basket and had the cush drive rubbers replaced at the same time as my gold z650. See https://sidyoung.com/z650-clutch-cush-drive-replacement/

Clip-On’s and switchgear

Also on the front of the bike, I’ve started experimenting with some zx10 switchgear and I have some after market clipons to install. With regard to the clip-ons, I sourced these originally for this project and they look great but I had a great deal of trouble fitting the blinkers off the end as the fitting is too large to fit in the tube. Some design time and experimental fabrication with some solid neoprene saw that solved and I now need to fit everything up and assemble them to the front end.

zx10 controls and after market clipons.

Swingarm

Rather than use the original steel swingarm, I decided to use an Alloy one from a later model Unitrack machine. I bought it sign unseen and it appears to be from a GPz550 or 750. I intend on making it into a dual shock swingarm to keep some originality so I need to fabricate two mounts and get them TIG’d onto the swingarm.

Exhaust

The final exhaust design will see the exhaust exiting above the rear wheel and under the tail light. I’m currently trying to work out if there is sufficient room

-oOo-