Custom Rear End For My Kawasaki.

[P.K.]

Note:
I recently posted this in the "Project of the day" tread but realized it probably wasn't the right place.
Also, I'm planning to post some more from this project later on, so I started a new thread here instead.


Hi

I'm into customizing motorcycles and I'm currently building a new rear end for my Kawasaki H1.
Early in the project I decided to use a rear wheel hub from a 78 KZ750. After a while I decided that this hub is uglier than a monkey's armpit, so I set out to modify the hub just to make it look better.

Here are some pictures taken during the process.

First the "before and after" picture.


I used the big press at work to get that ugly flange off.


Flange removed and hub sand blasted.


I made a two-piece mandrel for chucking the hub in the lathe.


Mandrel fitted.


Center drilled in the other end.


This is close to maximum diameter for my small lathe.


Finished hub machining.


In this mosaic picture I'm making a new flange to replace the one I removed. The flange is made out of 20mm thick cast aluminum plate.


The finished flange.


I made an interference fit between the flange an the hub. The flange will be heated to 200 deg celsius before placing it on the hub.


A guide pin was used to "synchronize" the spoke holes.


The finished hub, drive side.


The finished hub, brake side.

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[kd4gij]

Very nice work.

 

[jeff_g1137]

Hi
Are the spokes smaller ?

 

[Sitting on Blocks Racing]

Beautiful!

 

[P.K.]

Hi
Are the spokes smaller ?

I' not sure what you mean.

The original KZ750 wheel would have 4 different spokes because the right flange is smaller diameter than the left flange.
I made my new aluminum left flange such that left and right side spokes are identical (i.e. equal diameter on the spoke hole circles). This means I only needed two different spokes (inner and outer).

The spokes were special ordered from Buchanan's Spoke & Rim, who also delivered the rim correctly drilled for this hub. All they needed was a drawing of the hub.
The rim is EXCEL 4.25 x 18" (WM9) aluminum and the spokes are stainless steel.

 

[P.K.]

Here is my Kawasaki H1 that will get this new rear end installed sometimes this winter.
The whole idea is to modify a 70's classic with modern components for increased handling and power, and to do so without loosing too much of the 70's look.


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[P.K.]

OK, back to machining.

I certainly wasn't going to fit a stock KZ750 brake rotor to my modified hub. They are humongous and wouldn't fit with my "modern components" scheme. Modern R bikes typically have a 220mm rear brake rotor so I needed to make an adapter to fit one of those modern rotors to my hub. Normally I would have parts like this water-cut and then apply some finish machining, but in this case I wanted to machine one from scratch with the help of my new rotary table. It was a bit of a challenge considering the shape I had given this part.

Here are a few pictures.








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[jeff_g1137]

Hi
I meant the length of the spokes
Very nice work.
What size of lathe have you got, & mill ???
Have you any photos of the Lathe & Mill.
Love the bike, i have a 2004 BMW gs1200, my m8s had the H1 in the 70s, i think i had a 750 Custom

 

[P.K.]

Hi
I meant the length of the spokes
Very nice work.
What size of lathe have you got, & mill ???
Have you any photos of the Lathe & Mill.
Love the bike, i have a 2004 BMW gs1200, my m8s had the H1 in the 70s, i think i had a 750 Custom

The lathe is a HBM 290 Vario, an 11x27 bench lathe with a 38mm spindle bore.
The mill is a HBM 45 Profi, a basic Rong Fu 45 clone.
Cheap Chinese machines that can be found as a dusin different re-brands around the world.
Some pictures here: Lets See Your Shop!

 

[P.K.]

Next up was the caliper bracket. The chosen caliper comes from a 2008 Ninja EX 650. The bracket that came with this caliper didn't fit very well with my swing arm so I decided to make a new one.
This is an example where I have the part water-cut and just do some finish machining afterwards. If I had a CNC mill I would have machined the whole part instead.

The water-cut blank next to the Ninja bracket.


I'm using a two flute 20mm mill with carbide inserts. It became obvious that my mill doesn't have enough rpm for this kind of tool.


Polished carbide inserts for non-ferrous metals only.

The caliper bolted to the bracket.


A rough check to see if it fits.

I made a stainless steel sleeve for the axle hole and it's a press fit.




I'm not just winging this a I go along. I actually have a 3D model and I make drawings of all the parts.

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