Hi ronmar. My Metro came with a frame made out of some 1/8" wall box tubing and 1/4" thick channel iron and angle iron. I would have used a little thicker metal if I was starting from scratch but what's here is OK, the frame weighs about 150lbs. Then there is the weight of the ST 7.5 head and a golf cart motor. Myself standing on the same end as the golf cart motor probably about equals the weight of the ST head on the other end and I'd guess the whole diesel powered pogo stick weights about 1500lbs
. There are 4 nice 6" cast steel wheels built into the frame. It just sits on the dirt and the wheels mash into the ground and keep the whole thing from migrating. For balancing I set it on 2 1" pipes sitting on top of 2 6' pieces of 5" wide channel iron that I carefully levelled and tethered it with bungee cords. Right now the wheels are sitting in the channel iron and the whole thing jiggles around a little but the wheels never lift off the ground. Before I added the extra weights you would have to see and better yet feel it hop
! Just unbeliveable!! The first time I saw it do it's pogo stick trick I just burst out laughing, I've never seen anything like it
!! It hops best just above idle, maybe around 250 RPM. As you increase the speed it hops a little higher but I chickened out at about an inch and 300 RPM
! Though it's a great ride it seems dangerous and the faster it goes the shorter the time between up n' down strokes. If someone had the balls it would probably top out at about a 2" lift and then get smoother as the RPM increases. At 650 RPM it might just dance around like it does now even without my balance job because inertia and time would combine to tame it. If the whole thing was bolted to a massive weight a person might not notice it had a balance problem because above some RPM ( WAG, 400 or 450 ?) there wouldn't be enough time for the whole assembly to react. The frame the engine came with is about 6' long and just over 3' wide and weighs probably 150 lbs. so the engine won't tip over very easily but it can hop up and down like a pogo stick. I'm pretty sure that there is a downward thrust also when the piston/rod reverses direction at the bottom of the stroke, it might be fun to bolt the engine/frame to my utility trailer and take my home made weights off
! Leland
