Phantom Article

I came across this article on the Phantom and found it to be very inspiring! Here's the link:

http://deansgarage.com/2012/ron-wills-turbo-phantom/?show=gallery

Merry CHRISTmas!

Direction change - rear end

I have decided to fabricate the rear swing arm and use automotive parts rather then motorcycle parts for it. I think it would be difficult to balance the brakes when comparing the size of the front brake pads to the rear motorcycle brake pads.

I have purchased a spindle, hub, caliper and CVC joint from a 91 Topaz. It has the same 4 X 4.25 bolt pattern as the Mustang II hubs. I plan to machine the "bell" portion of the CV joint and weld on a flange to mount the sprocket. The back side of the spindle can be machined flat, and it looks like I can get three mounting bolts into the spindle. It will mount flat on a yet to be designed swing arm. The spindle mounting bolts will go through slots in the swing arm to allow adjustment of the chain tension. The bolt will thread into a mounting plate with a rear pointing threaded stud for applying chain tension. Should be interesting!

Just purchased the "hobby" version of Alibre CAD software since my old copy of Solidworks died. Looks like it will be easy to use.

Disc brake parts, spindles & wheels

The rear swing arm, wheel and caliper have arrived! I think the conversion will be pretty simple. Welding a truss that arches over the rear wheel to increase torsional stiffness will probably require cutting the bike frame just behind the middle part where the engine & swing arm mount. Should work out fine. Also, the axle that came with it is bigger than the one that came with my "basket case" so I think it will be fine.

Picked up the Mustang II spindles and a couple of nice wheels to go on them from a wrecking yard. I opted to stay with the 4 bolt hubs since the rotors looked to be in good shape and some decent wheels were available. I plan to rebuild the calipers and replace the wheel bearings & seals.

I plan to separate master cylinders for the front and rear brakes. Balancing will be accomplished with an bar between them that will allow moving that attach point for the linkage to the pedal. The Indy Cycle used Ø5/8 bore cylinders. Out of curiosity, I have put together a spreadsheet that takes into account the area of the brake pads, the arm length from the center of the pad to the axle and the cylinder size difference of the front vs the rear caliper. Also considering the fact that there are two brakes in the front and one in the rear. Ignoring differences stemming from the brake pad materials, I want to get a rough comparison to the front and rear brake system from a purely mechanical standpoint to see what size(s) the two master cylinders should be if I use Ø5/8 bore for the rear one. I am shooting for a 60%/40% front/rear brake balance as an estimate to start with.

Rear swing arm - Got syrup? I've got Waffles

Due to the difficulty in scaring up funds to get this going, I have decided I can save a bit of money by using the Ninja frame and swing arm. I think I can overcome some of the twist issues by beefing up the pivot pin and adding a truss across the top of the swing arm. I am also going to resort to either the Fred Flintstone or Huck Finn methods of reverse for now.

I have ordered a rear swing arm and everything attached to it from a 2009 Ninja EX500. It has disc brakes instead of the manual drum brakes on the bike I have now. I think it should bolt in. I hope. Having hydraulic brakes will make it much easier to balance the brakes after I am done. I may make a new read disc and caliper mounting bracket though. Increasing the diameter of the rotor would give the rear brakes more stopping power than stock without a major system change. The faster rotor speed would probably wear pads a bit faster, but that seems to be a fair trade off.

I will post pics of the conversion at some point.

Rats.....

I went to pick up the front spindles last night and it was a newer mustang with front struts instead of the Mustang II type with upper and lower control arms like I need. Guess I'll just have to man up and go the the local wrecking yard.

Waffling - again... and gathering parts

I am leaning back toward building a two seat tandem design. Glad I'm not actually cutting any metal yet and don't plan to until I have the basic parts gathered up. Yesterday I received a rack & pinion off of a 1976 914 Porsche I purchased off of Ebay. I sniped it for a great deal (I love doing that!) and am happy with its condition. I have located the front suspension off of a mid 80's Mustang at a local wrecking yard that I hope to pick up next week some time. I will be using the front spindles, calipers & rotors. I am still looking for wheels, parts for the rear swing arm, and another caliper and rotor for the rear wheel. I will also need to gather up some misc hardware parts and a couple of adjustable shock absorbers. I think at that point I would be ready to buy some tubing and put the chassis together. Seems like I usually start these projects too soon and stall out waiting for the $$ to buy parts. I am hoping this time that buying parts first will help me to finish this project.

Reverse Gearbox

I have been poking around the web looking for a way to add a reverse gear to my project since the motorcycle I am using does not have one built in. I have found some planetary reverse kits for buggies and some for harleys and one for bikes in general. The sets for buggies looks too small as they were advertised for 125cc & 250cc engines. The Harley set is specifically for the Harley, so that's out. The last one is here: http://www.roadstercycle.com/ and is about $1200. Looks like it might be made from Chevy parts, but I'm not sure.

Here is another page in a blog from Dan Lenox describing how he used the planetary gears out of a C4 transmission to add a reverse drive. http://www.briery.com/vortex/reverse_operation/reverse_operation.html

This piqued my interest and I have started doing some research. It looks like it might be possible to get a 1:1 through drive, reverse, about a 30% overdrive and maybe even a granny gear out of this type of a system. Certainly some design challenges, but it looks interesting. I am going to start poking around for a C4 or C5 tranny I can tear down and play with......

Swing Arm Debate

There are three approaches that can be taken on the swing arm issue. They are:

1) Modify an existing motorcycle swing arm to accept a larger pivot shaft, add support structure over the top of the wheel to improve stiffness. - I suspect that the dissatisfaction in the final results would off set any real or percieved effort that might result from taking this approach. This is a piece of the chassis that is important and needs to be done right and not cobbled together.

2) Scratch build a swing arm similar to the arm on the Vortex. This solution is probably the stiffest design for the lowest weight. It does make tire changes difficult but that shouldn't be often enough to be a big deal. It also has the advantage the ability to align the rear wheel and tighten the belt / chain drive without shims. Here is a link to one that is very nicely done. http://www.briery.com/vortex/rear_suspension/rear_suspension.html

3) Scratch build a cantilever swing arm (one sided). This would make tire changes easier, but aligning the rear wheel would likely require shimming. Yuck. On the plus side, I think the front hub from a FWD or 4x4 could be used, the yoke that normally connects to the drive shaft could be reworked for mounting the drive sprocket and the stock disc brakes from the donor vehicle could be reused.

Chassis Design - Revisited

This weekend a FireAero went up for auction on Ebay at a GREAT price. Too bad I can't jump on it. One of the things that has been done is a Vortex style swing arm has been built. Using the motorcycle rear end is the one thing that I have been waffling over. On a motorcycle, it will see very little in terms of side loading. On a car, that is not the case.

Body roll and rear end twist are two things that I have been concerned about. Jim Musser's front end design addresses the body roll problem. A fully supported rear swing arm is the best solution for the rear twist problem. Here is a video clip showing the problem pretty dramatically. It is a Venom three wheel car doing a donut. Watch how much the body is rolling to the outside of the turn as it comes around, and watch the twist in the rear end, especially on the first turn before the tire loses traction. http://www.youtube.com/watch?v=xcUjkrh_L_A&feature=related

In light of this, I am considering focusing my initial efforts on developing a somewhat "universal" three wheel chassis. If all of the suspension, steering, final drive and reverse issues are solved, and several standardized mounting points can be provided for the engine, then the task of a builder would be simplified a great deal.

I will discuss the two swing arm options I am considering in another post.

Ninja reassembly

This weekend I received a Haynes manual for the Ninja. The bike was in several boxes when I bought it so it should be entertaining to put it back together and get it running. With a 110 mile daily round trip commute, the gas price hikes we are being warned about have me concerned. I used have a road bike, but really don't like the thought of riding a motorcycle on the road after losing some family members to bike wrecks. However, in today's economy we just keep getting backed into a corner financially and have to keep making the most of what we have available.

On the upside, it will be fun putting a bike together. I haven't done that since I as a kid and am excited to do it with my boys if they are interested. My sons are 12 and 15 years old.

Front suspension discussion: Jim Musser

Today I called Jim Musser, designer of the Sport Cycle and he was very helpful in explaining how the front suspension achieves the very high roll resistance demonstrated in the Sport Cycle. I asked if the stiffness was achieved because

1) the pivoting frame that actuates the shock absorber is positioned across the vehicle, attached to both sides of the frame

2) the two lower control arms are tied together through the linkage.

He explained that the stiffness is a result of the fact that the two lower control arms are linked together. During normal cornering the outside suspension goes into compression and the inside suspension goes into rebound. Linking the two sides together through the shock frame forces the wheels to move together and that resists body roll. The stiffness of the shock frame is also a factor and lengthening the shock frame to fit the wider chassis will likely require some stiffening of the shock frame to resist torsional distortion during cornering. He also mentioned that he originally thought he had invented a unique suspension system but later discovered that some European race cars had also done the same thing.

He also mentioned that the chassis on a three wheeled vehicle does not need to be as stiff as on a four wheel vehicle because all weight transfer during cornering happens only at the front rather than front to back as in a four wheeler.

We also discussed the concern of CG location in a side-by-side arrangement and the asymmetrical CG position caused by a single occupant, resulting in reduced roll over limits. I mentioned that I plan to move the passengers forward a bit to improve CG. He also thought that a two seater would be better received in the market than a single seat. While marketing the resultant vehicle from this effort is in the back of my mind, my primary objective is to complete one for the fun of the project and to enjoy driving a vehicle I have designed and built. Whatever will be will be.

Frame layout: Tubing size

Looking at the photos from some of the other vehicles I have been referring to, I am a bit uncomfortable with the tubing sizes that some of them use. My primary reason is because of crash protection.

Jim Musser's chassis is the most attractive to me because it forms some protection around the occupant. The tubing he employed was 2.00 inch square tubing with 0.12 (1/8 inch) wall. I like that, but wondered if there was a readily available square tubing that might be an improvement.

I have settled on 2.00 x 3.00 x 0.084 (14 gage) rectangular tubing. It is about 10% lighter than the 2.00 x 0.12 square tubing, and is about the same stiffness in the 2.00 direction and almost twice the stiffness in the 3.00 direction. Orienting the 3.00 side vertical in the bottom rails and the 3.00 side horizontal in the top rail of the frame should result in a stiffer frame with a minimum weight penalty. A stiffer frame should be better for performance and definitely better for crash protection.

Design Rationale: 6 - 8 inches ground clearance

The Sport Cycle has about 4 inches of ground clearance. Last summer, I built a Marauder recumbent bicycle as designed by http://www.atomiczombie.com/ It had 4 inches of ground clearance and it dragged when I rode it over the hump where our driveway crosses an irrigation canal. I modified the frame to 7 inches of ground clearance and that seemed to be a good number.

Design Rationale: Aluminum body

I know that fiberglass seems to be the ideal material for building a custom, one-off body. The problem is that;

1) Any time I work with fluids I make a huge mess and am rarely happy with the results.
2) I have been sensitized to chemicals in the past and don't want to repeat that experience.
3) The resulting aluminum body should be lighter than a fiberglass version would be.
4) Working with aluminum sheet metal looks like a ton of fun and a natural extension of my current skill set. I also think that once I am tooled up and have some experience with aluminum sheet metal that I will be faster working with it than with fiberglass.

Design Rationale: Non-tilting design

There are a number of 3 wheel vehicles that have been or are in the process of development that utilize tilting, like you see in a motorcycle going around a corner. There are huge benefits in handling with this approach and it has been a real temptation to incorporate this feature into the design.

However, there are some very big challenges to a tilter that I won't elaborate on here. Because of the scope of the project without the added complexity of a tilting design I have elected to stay with a conventional steering system. This project is on my "Bucket List" and I need to keep it reasonable if I am going to get it done.

Design Rationale: 500cc Ninja powertrain

A variety of engines have been used for vehicles similar to what I am working on. The XR3 and the MAX both use small Kubota diesels. The Indy Cycle built by Jamieson DuRette uses a 750cc motorcycle. The Sport Cycle by Jim Musser was designed around an 1100cc Kawasaki. One of the Sport Cycle kits that Jim produces was powered by a 600cc bike. The HyperRocket is powered by a 250cc Ninja.

Fuel mileage for the XR3 and MAX is in the 50 to 80 MPG range. The Sport Cycle with the 1100cc engine gets about 45 MPG. The HyperRocket gets 100 - 125 MPG.

Initially I settled on a 250cc Ninja, largely based on the performance of the HyperRocket. However, the HyperRocket was developed in Michigan and I live in Montana. My commute includes some moderate hill climbs and I believe the frame on my vehicle will be heavier than that of the HyperRocket. In a conversation with Jim Musser, he shared that the Sport Cycle that featured a 600cc power plant still had excellent performance, I decided to look for about a 400cc bike.

Knowing that I might have to gear the bike down using a larger rear sprocket, a 6 speed transmission and the capability of high RPM would be important in order to meet quick performance and sufficient power required for good handling in traffic and hill climbs.

I found a 1989 EX500 Ninja on Craigslist for $300 - in boxes - but the price is right. The odometer shows 6800 miles, so I snapped it up.

Design Rationale: 1000+ mile range on a tank of fuel

Life for our family tends to be paycheck to paycheck - maybe you can relate. With this range, I can fill the tank on payday and it should be sufficient to make it to the next payday. 'Nuff said.

Design Rationale: Enclosed cabin

Many of the three wheeled vehicles out there or in development have open air cabins. I plan to use this vehicle as a daily commuter when we don't have snow on the ground, so an enclosed cabin is a must. This does present a more difficult project with particular challenges regarding sourcing glass. My garage is also typically used for projects, not parking, so I don't want this thing becoming a stagnant "car pool" in the winter time.

Design Rationale: Good in-traffic performance

My father-in-law has often said, "If you want to look successful, find a parade and get in front of it."

I also remember hearing a statistic in the 1980's that there were more VW vans in front of traffic jams than any other type of vehicle.

No one wants to drive a slug. It is a matter of both pride and safety to have a car that handles well in traffic, climbs hills reasonably, and corners safely.

Design Rationale: 85 MPH performance speed

I say 85 MPH performance speed because I live in an area where speed limits on the interstates is 75 MPH. I think a car needs to get to 85 MPH in a reasonably quick, responsive way in order to be safe during passing. Above 85 MPH is excessive and an endangerment on public roadways and should be reserved for the track. Sorry - I guess I'm just getting old. Will this vehicle go over 85? Shouldn't be a problem. But that is not my purpose.

Design Rationale: 75+ MPG

Originally my goal was 100+ MPG since my daily commute is about 110 miles round trip. The HyperRocket achieve that and more. However, since its seating is tandem and I plan to be side-by-side, and because I am planning to build a more substantial frame to improve crash protection, my goal has been adjusted to 75+ MPG. Currently I plan to burn gasoline. A conversion to propane is a real possibility also.

Design Rationale: 2 seat side-by-side

My initial purpose was to build a 100+ mpg car and the best way to do that is to keep it as small and light as possible. That meant one seat. However, I know that this may be the only car I ever get built (God willing) and after all that work, not being able to share the experience with someone else would be very disappointing. It would be incredibly fun to drive, though. There are several on the web. The Sport Cycle designed by Jim Musser is a great design. I especially like how he has designed the front suspension to prevent body roll while cornering. I will be using the same concept in my design. You can check out the Sport Cycle here: http://autos.groups.yahoo.com/group/IndyCycleOwners/ Another nicely done single seat was built by Jamieson DuRette and you can check out his version here: http://www.indycycle.net/IndyCycle/indycycle.html

Enter the 2 seat tandem design. I actually started laying out the chassis for this version, but a ride I took in a Varieze airplane kept coming to mind. It is a two seat tandem design. While I enjoyed the ride, it felt very "disconnected" from the other person. One interesting design along this line is the HyperRocket. You can check it out here: http://ecomodder.com/blog/hyperrocket-125-mpg-100-mph-3wheel-motorcycle/

Enter the 2 seat side-by-side version. I have two main objections to this design, namely 1) increased frontal area will result in higher drag and 2) the asymmetrical loading while only occupied by the driver affects the handling in such light vehicles. In spite of these two disadvantages, I can't imagine not being able to sit beside my beautiful, sweet wife, Julie, while driving down the road. She likes this one the best too.

So now I have adjusted my target on the fuel mileage to 75+ mpg. I commute 55 miles each way to work every day, so it would still be a great improvement.

The only problem with the 2 seat side-by-side is that I will have to remove part of a wall in order to get it out of my shop after building it. At least its not in a basement where I would have to dig a tunnel also.

Design Rationale: 3 wheels, 2 front & 1 rear

I have long felt that a three wheel design has significant advantages over a four wheel design, and that putting two wheels in front with proper attention to CG would satisfactorily address the rolling tendency associated with 3 wheelers. R.Q Riley, developer of the XR-3 and other 3 wheel vehicles, has excellent articles discussing 3 wheel vehicle designs in detail, so I won't repeat that here. His web site is http://www.rqriley.com/

Three wheels also has the advantages of lighter weight and reduced mechanical complexity. Powering the vehicle through the single rear wheel gives the option of "bolting up" (sort of) an existing motorcycle frame as the drive train. This saves a great deal of build time.

Lastly, three wheel vehicles are recognized as motorcycles in many states, and this helps with licensing and insurance requirements.

Design Parameters

Design goals for the Sport Trike 2x are:

1. 3 wheels, 2 front & 1 rear
2. 2 seat side-by-side
3. 75+ mpg
4. 85 mph performance speed
5. Good in-traffic performance
6. Enclosed cabin
7. 1000+ mile range on a tank of fuel
8. 500cc Ninja powertrain
9. Non-tilting design
10. Aluminum body
11. 6 - 8 inches ground clearance