Sunday, March 20, 2011

Part 8 - Regulator and CNC Switch Mount

The original plan was to mount the oil filter and regulator on a nicely chromed dual mount (see Parts blog). It didn't fit on this frame most likely due to the single down pipe.

The alternative was to fabricate a mounting bracket for the regulator and purchase a new oil filter mount that attaches to the EVO motor in traditional Harley fashion.

Alternator and voltage regulator

To create the mount, a heavy duty aluminum angle extrusion left over from a previous project was used. Cutting it to size was the usual death defying feat involving a chop saw and a huge amount of luck. Not recommended.

Regulator mounting bracket - front view

Regulator mounting bracket - rear view
The regulator is mounted to the bracket with 2x 1/4-20 SHCS. The bracket was tapped so eliminate nuts.  The other 2 holes are 3/8 clearance holes for the front motor mount bolts. The bracket is bolted to the underside of the frame and held in place by the the front motor mount bolts.

Regulator mounted

The ignition switch was next. There are a number of switch mounts available but decided to fabricate a custom part from 1/4" 6061-T6 aluminum plate. The switch mount also serves as a spacer for mounting the ignition coil to the top motor mount. Without the spacer, the ignition coil would be resting on the cooling fins of the cylinder.

The basic design was sketched on a piece of paper taking measurements directly from the top motor mount and the ignition switch. The paper sketch was then detailed using a CAD program - Alibre Design.

After messing around with a number of different designs, the basic design shown above was as far as my creativity would stretch. The vertical slots were added to create visual interest and serve no practical purpose whatsoever. After the CAD model was completed, a 2-D drawing was created and exported to a CAM (Computer Aided Manufacturing) program. 

Toolpaths for cutting the part
The toolpaths were created and downloaded to a CNC controller (Mach 3) which controls a homebuilt CNC machine that profile routes the part. The CNC machine was built from scratch a couple of years ago. 

Going from paper, to CAD to CAM to CNC Controller may seem like a lot of steps to get to the end product but the accuracy and finish of the part makes the process worth while. Cutting the part out by hand would take significantly longer and the slots would be a real challenge to keep straight using hand tools.
CNC Machined switch mount

Switch mounted
The switch mount still needs to be polished to match the shine of the primary.  

Sunday, March 13, 2011

Part 7 - Starter motor

An Ultima Thunderfire 1.75kW starter motor was ordered for the bike.

The chrome on the starter motor wasn't up to the same standard as the other components from Ultima.
You can see the copper layer in the circled area below. Not a big deal considering that it is hidden when the starter is installed but still surprising that it was shipped by the manufacturer with an obvious cosmetic flaw.

Before the starter can be installed, the starter gear assembly needs to be assembled to the starter motor. The starter gear assembly comes with the primary. The parts attach to the starter motor shaft in the order shown in the image below. Begin by sliding the spring stop over the shaft, followed by the spring, starter gear spacer, starter drive gear, starter gear bushing and finally the starter bolt. 

Parts required for starter gear assembly in assembly order

Starter gear assembly before fastening

Starter gear final assembly

Mounting points (click to enlarge)
Two 5/16-20 2" SHCS (grade 8 if you can get them) are required to bolt the starter motor assembly to the primary motor plate. The motor plate has an alignment pin to ensure correct alignment of the starter with the ring gear on the primary pulley. Looking from the back side of the motor plate you can see the alignment pin and the edge of the ring gear. Further out is the gold colored bushing that supports the starter drive gear when it extends outward to start the engine. This must be lubricated. The bushing is housed in the starter gear cover and should be removed before installing the starter so that you can see what you are doing. Slide the starter into place over the locating pin and fasten the 2 bolts. Everything is being mocked up to ensure proper fit so nothing is being properly torqued or loctied now. Unless this is the final fitment, you want to take it easy on the spinach and avoid tightening the bolts to more than snug - just enough to hold everything in place. Looking from the primary side of the bike you should see something like this:

Starter installed viewed from primary side

The starter gear cover can now be replaced which will leave you with the complete assembly. There is a single post on the starter motor that gets connected directly to the battery positive. This requires a heavy duty cable as there will be hundreds of amps flowing through the cable when the starter is engaged.

Battery cable set

Starter gear cover replaced

Starter installed

The hole diameter of the battery cable ring terminals is too small for the starter motor power stud. Nothing a drill can't fix but it is clear that the wrong part was ordered. Details details details. 


Sunday, March 6, 2011

Part 6 - Motor, primary and transmission

The motor arrived on Friday. From time of order to delivery was exactly one week with free shipping (except for the lift gate fee that I elected to pay to simplify offloading at home).

The boxes - motor, primary and transmission

Motor: Ultima Black 113 ( 1850 cc ) EPA compliant
Transmission: Ultima 6 speed Black RSD hydraulic clutch
Primary: Ultima Drag style 85mm belt drive
Ordered from Jireh Cycles :

After everything was removed from the boxes, the motor was placed in position on the frame. All the mounting points lined up correctly but the motor ships without any mounting hardware. A quick trip to Ace hardware was required to get temporary 3/8" mounting bolts. Used 2" long bolts in front and 3 1/2" bolts for the rear mountings. A chromed motor mounting kit from Gardner-Westcott is on order for final assembly. The motor is very heavy (160lbs) so I suggest you get help lifting it into the frame. Naturally I did it without help.

Motor positioned in the frame

The next step was to mount the transmission. The transmission has 5 mounting studs. 4 of the studs go through the slots in the frame mounting plate. According to Mike at MMW, the 5th stud can be cut off. It's not needed. The slots let you move the transmission forward and backward so that the primary plate that connects the motor and transmission can be properly installed. At this stage the motor and transmission mounting bolts were left loose.

Transmission mounted to the plate behind the motor

Motor and transmission loosely mounted

The primary consists of a lot of parts so the assembly is more challenging than the motor and transmission which arrive fully assembled. The Ultima instructions are very clear. At this point I did a mock-up of the assembly just to make sure all the parts were in the package and that everything fit correctly. The primary will need to be disassembled in future and then re-assembled using locktite and the correct torque specifications.

Primary parts

The primary motor plate locates over a ring feature on the motor and a pin that extends out of the gearbox. With the motor and transmission loose with respect to the frame, the motor plate was used to jockeyed them into position creating the correct distance between transmission and motor. The primary motor plate is bolted to both the motor and gearbox fixing them with respect to each other. The entire assembly was them straightened with respect to the frame and the the motor and transmission were snugged to lock everything into place on the frame.

Primary rear plate connects the motor to the transmission

The front and rear pulleys and belt were installed next. It was a real battle to get the front pulley onto the splined motor drive shaft. I was worried that it might get stuck so didn't force it on the whole way - I need to disassemble this when mock-up is complete anyway.

Front and rear pulleys installed

Next up is the clutch. The clutch consists of a series (I lost count) of alternating steel and fiber plates which are held in place by the pressure plate
Clutch installed

The motor and transmission pulley caps cover everything up and provide an edge for keeping the belt on the pulley. The caps are bolted to the pulleys.

Motor and pulley caps installed

The last step is to line up the outer cover with the support shafts and bolt it into place. It's not really a cover in the traditional sense but that's what the manufacturer calls it! The outer cover caps have bearings in them which slide over the bosses on the pulley cover caps. This provides extra support for the pulleys.

Driveline installed


Thursday, March 3, 2011

Part 5 - Driveline, Hand Controls, Mirrors and more

Some major parts arrived this week - the hand controls, transmission and drag style primary. The primary consists of about 6 boxes - definitely some assembly required! Fortunately there are instructions. Mocked up the hand controls and mirrors to see how things will look. Decide for yourself.

Drag style open primary

Right side hand control and mirror


The shipping company called to say they would be delivering the motor on Friday. Too many parts, too little time!