Post 21: Considerations about the 3 wheeler chassis design

     The problem with the chassis design I proposed with an offset main "beam is that as it gives the driver more space, it reduces the space for the passenger, which means that accommodate a passenger, the body would have to be even wider than the Lotus 7... 

     So one big question to answer is: build a wide two seater, or a narrow one seater?

  Unless of course I use a surround space frame and no central beam at all. The reason for the central member of the frame in the Lotus 7 design is that it is a 4 wheeler with a rear live axle, and a shaft between the transmission and the axle. The purpose of the center well is to house the shaft which moves up and down with the wheels. Now, in our case, the shaft does not move up and down, and if the engine and the rear wheel attachment point are low, it will barely stick up from the floor of the car

     

Post 20: Lotus in the shop...

  Well, I took the Lotus to the track on Sunday, and had a bucketload of fun. I was there at 8:30 or so, and the Autocross track had just opened:

  There were a couple of young guys there with a Mazda Miata they had been prepping for Autocross, and they were fast. One of them took me around in about 43s. I was impressed.
  I ended up doing 6 runs in the morning, and 4 more in the afternoon with Mary, Todd and Charles as passengers. I drove as hard as I could, and that was pretty hard! My best time, a decent, but still very unimpressive 49s... I really have to work on the driving: the placement of the car in each curve (entrance and Apex), the smoothness, avoiding drifting too much, etc...
  Anyway, I loved it, and want to do it again.
   At the end of the day, we got to do a few "parade laps" on the main track. I was actually surprised at how fast they let us go, but since we were not allowed to pass, there were numerous slowdowns, especially before the hairpin curve. 
   Unfortunately, the car stated heating...
I added water at the service station after letting it cool, but it was spewing coolant on the way back, and hot again when we got back home. I added water again in the morning, but it started heating again after a while, so I took it to Hesco. 
  Turns out there is water in two cylinders, which means a blown head gasket, or worse possibly a cracked head. Bummer. And I am not sure exactly how it happened. I did push the car, but not all that hard, and am wondering if there was an existing problem with the cooling system that became suddenly critical on the track...

Post 19: Revised Mockup

  Since I am now definitely going with the double wishbone front end, I revised my earlier mockups based on the Bugatti:

  I extended the nose forward to provide attachment points for the front suspension arms and coil over shocks.
  I now think that an extremely rigid surround space frame chassis like the Lotus 7's is probably not as necessary for a 3 wheeler as it is for a 4 wheeler, and am considering instead using a rigid central "beam" connecting the rear wheel suspension unit to the front suspension unit. The beam would be built out of 1"x 2" rectangular tubing, and have a partial 1/32" steel "skin" to add rigidity.
   The basic idea is the same as the chassis for the Lotus Elan:

Post 18: Sourcing out parts

  I have been seriously looking at ATV parts for a few days, especially the Yamaha Raptor 66o double wishbone front end. I found a cheap set of used left and right A arm assemblies, complete with spindles and disk brakes. I also bought the coil over shocks that went with them:

  The whole thing is actually very similar to the LOTUS front end, just lighter weight, and will hopefully be strong enough to support the V-Twin 1100 Honda ENGINE.
   That will at the very least give me an easy starting point to experiment with. If the geometry work, I can get better chromoloy arms, new joints

 
and better shocks:

   I have been looking as several options for a manual Rack and Pinion Steering, considered the VW Rabbit option

 but finally settled on a 14" unit made for dune buggies and such, with 3/4 turn and 2.5" travel from center to lock:



    I have also been checking on front tires for the 16" Fat Boy aluminum wheels. The rims are about 3 to 3.25" wide, so the choice is very limited, but Cocker has a couple of options, and I will probably get a pair of $128 Excelsior Vintage 500/525-16:

Post 17: Riding on the Dark Side???

  Well, I didn't know the question was so controversial... The "Dark Siders" have been putting car tires on the back of their bikes for years, mostly for economy reasons, and it's a hot button issue for some  people...
   So it is definitely possible to put a 165/80/15 to a 205/65/15, on that Shadow rim, and since the trike is not going to lean, it's going to give me both a lot more traction and cornering ability.
  I am considering the Firestone 205/65-15:

Post 16: Back to the 3 Wheeler

   The Honda bike had been sitting in my workshop almost cut in half since fall, and I finally got around to finish chopping it off. My friend Charles helped finish the cut, and it didn't take but a few minutes to separate the front end from the back:

 A couple more judicious cuts will separate the engine frame

 from the rear wheels suspension unit:

   The rear tire is 170/80-15. I am wondering where it is possible to find an automotive tire to fit that rim...