collapse

www.dimecitycycles.com


www.restocycle.com

www.CITYLIMITMOTO.com

www.jadusmotorcycleparts.com

www.bisonmotorsports.com

www.speedmotoco.com

www.cognitomoto.com

www.townmoto.com

www.sparckmoto.com

www.Moto-Madness.com

www.pistonsociety.com

www.steeltowngarage.com

OUR ADS ARE FROM SUPPORTERS OF THE COMMUNITY - CONSIDER TURNING YOUR AD-BLOCKER OFF FOR WWW.DOTHETON.COM :)

Author Topic: Custom Racer with Aluminium Frame and Sportster Engine  (Read 2133 times)

Offline DM_Andreas

  • Posts: 21
Hi Guys,

as it's Winter now business is slow and me and the guys at the shop have some free time on our hands.

We wanted to try something new anyhow already since some time, so we decided to build a bike with a custom made chassis and bodywork.

It'll be certainly quite far away from the "standard" Sportster builds, but I hope you're still interested.

I'm trying to document the build here step by step....

Everything started with an old 2006 model bike...less than 8000 miles on the ODO.

Offline DM_Andreas

  • Posts: 21
Re: Custom Racer with Aluminium Frame and Sportster Engine
« Reply #1 on: Jan 17, 2018, 01:24:05 »
That's how the bike looked when we got it....




Offline DM_Andreas

  • Posts: 21
Re: Custom Racer with Aluminium Frame and Sportster Engine
« Reply #2 on: Jan 17, 2018, 01:24:35 »
The very first thing we did, was taking the bike completely apart.

We left only the Engine and some components from the electric system, nothing else will be used again.

Then came an important step, of which I don't have pictures (Unfortunately).

We measured up the engine, weighted it, and roughly determined its weight distribution.

Based on these specs, I've sat down and determined the overall specs of the bike we want to build.

We're planning to build a fast Road Bike, as lightweight and nimble as possible.

After some calculations I've came up with the following specs:

Rake 23.5 Degrees
Trail 98mm
Wheelbase 1480mm
Seat Height 825mm
Ground Clearance 245mm
Swingarm Angle 12.6 Degrees

At that time I already made a complete 3D model of the whole bike...But I don't want to show it now here,otherwise I'd just spoil the suprise

Based on the Height of the engine in the Chassis, we've build a small Prop-Table with an adjustable engine holder.



It's an assembly help.

It holds the engine in the same place as it would be in the bike later.

In this way we can start to assemble all the components around it, checking everything for fitment.

Offline DM_Andreas

  • Posts: 21
Re: Custom Racer with Aluminium Frame and Sportster Engine
« Reply #3 on: Jan 17, 2018, 01:25:02 »
Then the actual work on the bike started.

You can see here already the forks which we're going to use.

These are GSX-R 1000 Fork Tubes in GSX-R 600 Triple Trees with a GSF 1200 Wheel and Brake Rotors.

I've selected these parts because that combination gives me exactly the specifications I've been looking for.

The big tube on top is only a mock up.

It's a piece of stainless tube which has been cut to size and a Triple Tree Mount has been welded in at the desired Rake.

That assembly has been mocked up at the engine, allowing me to take measurements for the front engine mount.




Offline DM_Andreas

  • Posts: 21
Re: Custom Racer with Aluminium Frame and Sportster Engine
« Reply #4 on: Jan 17, 2018, 01:25:33 »
As I have now the reuired measurements for the front engine mount, the first few components could be designed.

The very first part is the steering head and front engine mount.

Here are some screenshots from my 3D models.





These are 2 parts, which are bolted together.

Both are CNC cut out of a solid block of Aluminum.

The steering head is also hollowed out from the rear, to save weight.

Why cutting these out of a solid block?

- It's extremly strong
- It gives you perfect control over the geometry. A welded assembly will never be as precise.
- I've never seen anybody else do it this way...so why not build something special ?!

Offline DM_Andreas

  • Posts: 21
Re: Custom Racer with Aluminium Frame and Sportster Engine
« Reply #5 on: Jan 17, 2018, 01:26:32 »
Once I've finished the design the guys at our shop machined the parts for me.

Here are some pictures from the process.

First the Steering Head...








Now the front engine mount...







Offline DM_Andreas

  • Posts: 21
Re: Custom Racer with Aluminium Frame and Sportster Engine
« Reply #6 on: Jan 17, 2018, 01:27:11 »
After a few hours on the Machine we ended up with this








Offline DM_Andreas

  • Posts: 21
Re: Custom Racer with Aluminium Frame and Sportster Engine
« Reply #7 on: Jan 17, 2018, 01:27:52 »
Test Fitting the front engine mount...







And now the Money shot..

Front engine mount, Steering Head and Fork Assembly


Offline DM_Andreas

  • Posts: 21
Re: Custom Racer with Aluminium Frame and Sportster Engine
« Reply #8 on: Jan 17, 2018, 01:28:34 »
Time for the first Test Assembly.

The top tube is 100mm OD Aluminum, tack welded to the machined steering head.

On the bottom we did a cut out, to get the engine closer to the frame tube.

Right now it's of course still way too long. It'll be cut to size later on.










Offline DM_Andreas

  • Posts: 21
Re: Custom Racer with Aluminium Frame and Sportster Engine
« Reply #9 on: Jan 17, 2018, 01:29:09 »
After the first components turned out nicely, the work can go on.

The next step is working on the rear section of the frame.

We'll be using the rear mount on the engine also as pivoting point for the swingarm axle...Just like the original Sportster does it, too.

The very first thing here is...our CNC...