Tool Talk

General Category => General Discussion => Topic started by: EVILDR235 on August 23, 2020, 05:42:02 PM

Title: Mini bike build and some recent old engine finds.
Post by: EVILDR235 on August 23, 2020, 05:42:02 PM
Well back in March I started a mini bike project. I finished it about 2 months ago. Most of the parts I already had. I worked on it a little each day not pushing myself to hard. Every night I would sit in front of the computer digging pieces of metal out of my hands. It is a Mongoose bicycle frame that I cut up and re-constructed. 3 hp Briggs engine with a home made intake manifold so I could use a NOS Tecumseh H35 side draft carb which is better suited for this that the original Briggs carb. I snuck it out one night for a test ride. The electronic speed sign said I was going 27 MPH when I passed it. It does need better brakes which I now have. Maybe this week I will redo the brakes before any more late night rides. The last mini bike was in 1965. My friend owned the bike and I owned the engine. My friend now owns 2 ex CHP Harleys and I am still riding a mini bike. As far as my garage, it is ever changing as I add more stuff. I recently picked up a 1944 Briggs model N and a 1960 Apache lawnmower in good working condition with all the original paperwork. You all stay safe.

EvilDr235
Title: Re: Mini bike build and some recent old engine finds.
Post by: international3414 on August 23, 2020, 06:26:16 PM
what was the yellow gas tank?
Title: Re: Mini bike build and some recent old engine finds.
Post by: Papaw on August 23, 2020, 07:47:47 PM
I rode and repaired motorcycles for many years, but never had a minibike. My two sons also never had one. The oldest started on a Honda MR50 at about 5 years old and rode quite a few bikes after that , but the younger son never did ride any bike at all.

I never got along with lawnmowers.
Title: Re: Mini bike build and some recent old engine finds.
Post by: EVILDR235 on August 23, 2020, 07:55:31 PM
A propane bottle. I have a second remote one I use so I can start any engine in the shop that doesn't have a fuel tank or a fuel tank with bad gas. I have changed the carb and can't use the original tank anymore. I built this bike for riding around the yard and driveway.

EvilDr235
Title: Re: Mini bike build and some recent old engine finds.
Post by: EVILDR235 on August 23, 2020, 08:13:44 PM
I grew up in the 1960's when we were flooded with small imported bikes. Everybody had a Honda Cub 50. In 1965 I got a Sears Allstate moped and discovered motorcycles can hurt you. I have chunk of meat missing from my left leg the size and shape of a orange slice because I was riding it with the flywheel cover removed and crashed into my friends garage when the throttle stuck wide open and it tried to eat me. I was lucky, I know 3 people that weren't.

EvilDr235
Title: Re: Mini bike build and some recent old engine finds.
Post by: amecks on August 24, 2020, 06:28:11 AM
My friend and I had two matching minibikes.  Square tube chopper frames and forks made in the welding shop we worked at.  Steering and front wheels from bicycles picked up along the road as I drove the company truck.  I sourced rear drive wheels from an industrial second hand shop.  Sears reel mower engines from the flea market -$5 each.  No clutch - push it along and jump on the seat to spin the rear wheel and go.  We would take them to the Interama tract in North Miami to ride them.  A buddy clocked me at 33mph.

So how do weld or braze a propane tank safely? 
Al
Title: Re: Mini bike build and some recent old engine finds.
Post by: Bill Houghton on August 24, 2020, 09:04:53 AM
My Honda 50 story is secondhand.  When I was young and living in Ann Arbor, MI, a coworker was being wooed by a guy who lived in Toronto, about 450 miles away.  He would drive his road Honda 50 (the kind with the plastic lower fairing, centrifugal clutch, three-speed transmission, top road speed downhill of about 50 mph) down every few weekends, spend a day trying to get Dorothy's attention, then drive back.  I imagine he spent the next week vibrating gently from the journey.

Between my first time there and my return a couple of years later, he'd given up, Dorothy never having been convinced that he was her shining prince.

I hope he found somebody.  That kind of determination deserves to be rewarded.
Title: Re: Mini bike build and some recent old engine finds.
Post by: EVILDR235 on August 24, 2020, 06:09:31 PM
Making the fuel tank I took a empty propane bottle and removed the two one way valves. I then pumped a lot of air thru it for a few minutes. I then drilled the fill hole in the middle of the side and drilled a smaller hole for the fuel petcock. I then drilled out the threads where the gas originally came out and cut new threads and then screwed in a piece of brass rod and cut it flush and soldered it in place. I then drilled out the threads in the other smaller hole and threaded it and screwed in a piece of brass rod and left it longer so I could use it for mounting the tank at the rear and soldered it also. On the original bottom of the propane bottle there is a hollow phony bottom that I pop riveted a another bracket to also for mounting. 

EvilDr235