Dienstag, 5. März 2013

#14 Raceknuckle

Carb again ... using the two barrel Weber DCOE40 causes two problems with this bike: first it is a really fat carb and occupies lots of room on the right side. It's a problem while driving since the leg or knee is covering the stacks. Also it's a cosmetic problem because it gets crowded as the exhaust will be on the same side.
Attaching the DCOE40 on the left simply looks weird and the manifold is too short (loss of torque).
Given this I decided to use a standard upright assembly which in turn means, exchanging the DCOE40 for an IDF40 down draft carb.

Since there's no manifold for IDF40 and Knucklehead that has each barrel and tube separated up to the heads' inlet (they are all 2into1 manifolds that in the end merge both barrels) I had to design one:

I call it "TheTubes" and it cost me quite a while to create the final version. It is twisted in the lower part, because I wanted to have the inner diameter of 39mm over the complete length of the tubes (of cause right after the top flange it goes from 40mm to 39mm). The inlet port of the head is 39mm as well.

I had a polyamide prototype made by 3D printing for fitment tests:

Fits as desired, exactly between both heads:

First thought for the final manifold was to have it printed in metal, AlSi10Mg, too. But ... after some inquiries I soon dropped that idea (the most expensive offer was about the price of the complete KN93 engine!). Currently I'm searching a metal casting company that is able to sand cast or precision cast that part. Next challenge to come is machining the flanges to measure.


#13 Raceknuckle

Bunch of parts ... needed for the bike but not very exciting I think. First of all the right foot peg with brake lever, designed:

And made ... part of the assembly is already nickeled:

Next is a seat bar, designed:

And made...the bushing in the CAD picture will be made once the leaf springs are finished:

Next holders for the oil tank that will be welded onto the frame, design:

They were laser-cut out of standard steel:


Montag, 4. März 2013

#12 Raceknuckle

Foot clutch and foot peg ... all-in-one. Had the idea to combine the classic harley foot clutch assembly with a smaller looking foot peg and started with some designs. Finally this one made it into production:

The foot peg on the lever snaps into a holder in the rigid, frame mounted part so it can take the load of the leg/foot. The friction drums are made of stainless steel with a friction plate taken from an Indian Chief:

All the spring and adjusting stuff is covered inside the housing. Final assembly shown below, plates are made of 10mm carbon fiber plate, the pivot is taken from a streetfighter peg:

And on the bike...


Sonntag, 3. März 2013

#11 Raceknuckle

Chain tensioner ... my first bike was a Suzuki enduro which was equipped with a chain tensioner. I appreciated the advantages of this device, so why not use one on a custom Harley? CAD design comes first:

Really a lot of small parts...

And the finished part. As you see, I used carbon fiber plates for the sides, made a short torsion test and it's really stiff.


Samstag, 2. März 2013

#10 Raceknuckle

Kicker pedal ... I wrote already that the Baker kicker arm wasn't mine. Same goes with the pedal, so, as usual, new part, home made. This time I reused the axle of the original pedal, shortened it a bit and added four ball bearings:

The outer pedal is made of 7075 (as all the aluminum parts I do) and fits nicely around the axles end plate.

Final finish: nickel.


#9 Raceknuckle

Steering damper ... even though the girder fork is original Indian Motocycles, I didn't like the adjustment wheel and decided to design and make a new one:

Turned ready, next step is milling the cutouts for gripping.

Finished and and added some engraving ("H*O*L*D* * *F*A*S*T", a little difficult to see on the picture).

Of cause final finish will be nickeled.


#8 Raceknuckle

Shift knob...I already bought a shift knob from GearHedz for my Pan many months ago so they were my first choice for making the knob based on one of their designs for the Raceknuckle.

All their work is hand made, no CNC, for sure that applies to the wooden parts as well as to the metal parts. There are two posts on their blog about the beginnings and the finishing of the "wrench biter".

Absolutely brilliant work!


#7 Raceknuckle

I have to admit that some of the parts I use are bought but most of them will be modified either way. While searching some hot rod stuff on the internet I found those really nice lights and gas cap:

Of cause the lights have to be changed a little bit in order to pass the German TÜV.

Transmission is a Baker 4-speed, not the 6-into-4 everyone uses, it's really too wide for my purpose. Added a luxury item, the N-1 shift drum, which reverses neutral and first gear order, so I now have N-1-2-3-4. Kicker arm and pedal that came with the Baker I found less appealing so the kicker arm was replaced with the strong arm from Fab Kevin:

"If it ain't steel it ain't real!" Oh yes, but it weights a ton! Not sure if I keep it or do something different ... and lighter of cause. Tried to reduce weight a little bit by adding an additional hole but fine words butter no parsnips.

By the way in the picture above you'll see the leaf springs for the seat attachment, derived from two sets  of seat springs from an American tractor.

Primary is from Evil Engineering. Took me quite a while to get it...


#6 Raceknuckle

All the work on the motor internals is now done. Parts are polished and laquered to keep the churning losses minimal, crank discs are lightened to a certain extent. It's not overdone since the bike will appear on the quarter mile but the main use is as a daily runner so focus here is on a stable idling. Sunglasses on!

That's how cases should look like. Simply beautiful.

We decided not to use the S&S cam that came with the motor but to switch to a Leineweber #3.

You can check the specs here if you like.


Freitag, 1. März 2013

#5 Raceknuckle

DCOE 40 carb. Nice quality but the velocity stacks included look a little cheapish. So I decided to make some new ones. I usually start with a CAD design of my parts and then fabricate them using mill and lathe (and what else is needed).

Just want to point out that these are not CNC made, this was all done with a normal, conventional lathe (ok, and some sand paper / polish...).

Looks good on the carb!