Grasshopper Clone

I’ve always liked the design of the HP Velotechnik Grasshopper. A compact SWB, fully suspended with 20” (406) wheels. I’ve been waiting to find the right heavy duty BMX pieces to build a copy of one.

For the main body of the bike I used pieces from this StrideWalker exercise machine. The tubing is 14ga (.065”) and 1.5” square. In the pics below you can see which sections were used and how they were arranged. The upright support behind the seat and the internal boom tube with bottom bracket are 1.25” square tubes from another exercise machine.

The Bacchetta recurve seat has been hanging around the garage for a while waiting for the right project. Seems like a good fit for this one. After sitting on the bike I found the bottom bracket to be a little too high at 34”. I cut the boom receiver and angled it down to the factory spec’d design of 26”.

The rear shock and the springs inside the forks have been upgraded. I reworked the rear triangle so I could use a shock with a little bit more travel. A little more progress made this Labor Day weekend shown below.

Created a Flip-it style mast and added wide, cruiser style handlebars. The seat braces are the original Bacchetta tubes cut short as the seat needs little adjusting to change position. I found some slightly larger round tubing and welded a short length onto each end of a ¾” square tube for the seat braces to slide through.

The original boom tube that goes inside the frame was a little short and needed a derailleur tube. It was easier to build another one and had a bottom bracket shell with a piece of seat tube still attached. When the boom is slide into the receiver on the bike there is a gap large enough that the pinch bolts won’t completely lock the boom down. Used a piece of plastic about the thickness of a 2-liter soda bottle for a shim.