Simplex 3 wheel Truck Tribute

[Ricks]

I've ordered so much stuff from Wayne, I should just put him on speed dial!  I'm also on the lookout for a gas tank for this project.

[Bob Gurkin]

Wow, you are spending some money. I recently saw a gas tank on Ebay, but it went out high.
Let me ask you a question about welding the frame. I have seen, on other forums, where the guys have raved about brazing the frame rather than arc welding. However, it would appear that the tolerances have to be very tight for brazing to work. I see you are mig/arc welding your joints.

According to what I have gathered from the other guys this type of welding weakens the frame, but I would think that the heat generated to braze the joints would weaken it also if this were the case. Also, I can't see how a brazed joint would be stronger than a weld.

What do you think of these arguments one way or the other?

What are your thoughts on this?

[Ricks]

I have not brazed anything since high school, about 25 years ago.  I don't see any problem with MIG welding.  If it was a problem, they would not weld race cars.  IMO, a weld is much stronger than a braze.  When I was first teaching myself to MIG years ago, I tested some of my welds and had to destroy the piece and the weld did not fail.  The key is to get good penetration.

Here is a chassis I welded in my old drag car that I felt comfortable in @ 130mph.

[chainmaker]

Nice work...Had to sighn on to follow it! Did you ever get info on the diff?

[Ricks]

I actually have a reproduction 3 wheeler manual that show all the parts for the axles, but nothing is available as far as I could find.  I'm going to go with a straight axle like on the early models.  Bill did send me some pictures of the pulley arrangement and such, and it should be pretty easy to replicate.

[Ricks]

Nice work...Had to sighn on to follow it! Did you ever get info on the diff?

  Chainmaker, I thought you might be interested in this.

  When out in Portland a guy had 2 simplex trucks that were missing there original drive axles.  He did 2 different things on each bike.  One he put a kart differential in by machining a pulley to bolt to the differential where it would normally have had a chain sproket( Picture 1).  On the other, he put comet style torque converters on the outside of a solid shaft, when the drive shaft comes up to speed, the pulley halves move closer together, which causes the belt to ride higher in the pulley, which drives the bike.  When you let off the throttle, the belt drops into the pulley and causes slack, which allowes the 3 wheeler to turn freewheel(Picture 2).  It was a pretty neat setup and I watched both run without a problem.
  After thinking about how the stock setup works, I'm going to try a third way.  I'm going to use a solid shaft to comet style clutches on each end, the type that usually go on minibike engines.  These will give me freewheeling action when not under load and that is what Simplex did on their later model trucks.  As a matter of fact, their outside clutches are the same as used on there automatic drive!  Including the use of the same brake shoes used on the front and rear brakes!  I find it very clever their reuse of parts in different applications(Picture 3).

[chainmaker]

  I dont know if this would help but I found these during a search   http://www.northerntool.com/shop/tools/product_35768_35768

[Ricks]

That's exactly what is in the orange and blue truck from the first picture.  These are readily available, and are a great option when using a stock motor.  With the honda motor I'm using, I will need to offset the pulley to one side, therefore I'm going to use the maxtorque clutches on the outshafts.

[Ricks]

Well, since I have finished up my 53 automatic, it is time to get back on the truck.  I have installed the mounts for the drive shaft and have the drive shaft mocked up.  I am going to go with belt drive clutches on either side of the drive shaft.  These should allow for free wheeling when not under power and allow the truck to turn.  After looking at Bob Legron's stock truck, Simplex used this arrangement, just with their own parts.

1st picture Bob's clutch,2nd max torque pulley clutch.  Anyone see a problem with this?

[Ricks]

Here is the drive shaft mounts tacked in.  Turns nice and smooth!

[Ricks]

I picked up a Comet CVT and am going to run it directly to the drive shaft.  With the clutches on the outboard ends, I hope to have some differential action.

[Ricks]

I laced up the wheels.

[admin]

Wheels and brakes test fitted.

[kartjockey]

I really love your three wheeler project. I have been studying all your pics. Very nicely done. I have been wanting to do a custom two wheeler with a Briggs. I have a passion for the Briggs and once drew up plans to convert a 5hp horizontal shaft to an overhead valve arrangement.  Swapmeet in my town is coming in May. Who knows what I will see. It's a bit of everything but mostly car stuff but last year I missed a rolling chassis Simplex that sold for $50. Uggg! Wife always says I don't need another project. Lucky for me I've worked in shops my whole life and I am a bit hard of hearing!

[Ricks]

Belt sheaves mounted and custom pulley clutches with roller bearings test fit.  I'm waiting on some belts to line up the clutches and to make some idler pulleys.