Tested Rackmount Chain Drive Kit Off Ebay

[Mike St]

I sometime back purchased a rackmount chain drive kit from Ebay which is no longer
available, and set it up with my 35cc Robin Subaru 4 stroke. The kit did work but
I found the Robin with the kit produced poor acceleration and unsatisfactory
power or performance. Something I proved previously is that the gearbox and
chain sucks off too much engine power. I once did a similar test with a
Robin friction drive, and the performance was much zippier. Friction drive
applies power directly to the wheel with no power losses. My options
are to replace the Robin on the chain kit with my Honda GX50, or
replace the entire chain kit with a friction drive and use either the Robin
engine or the Honda GX50. I am leaning towards the FD unit due
to max power to the wheel, ease of use and maintenance, and
reliability of FD. I'll buy a Maxxis Hookworm tire if I have to for max longevity.

 

[Sidewinder Jerry]

With the RS 35 you need a minimum of a 18\1 reduction on level ground with no hills. The Honda 50 needs a minimum of a 16\1 reduction on level ground with no hills. That transmission looks like at best its a 3\1 reduction

I can't tell if that's a 44t or a 48t if you have a 10t drive sprocket then at best your reduction is 13.2~14.4\1. So therefore your engine is over loaded. It will still be overloaded if you choose to use the Honda 50

 

[Mike St]

I did make all the ratio calculations before installing the kit so it was in the right range.
I had about the same results previously with a pocket bike gearbox and a chain using
a double right-sided drive of my own design. I have already replaced the kit with a
friction drive using a 1.25 inch dia roller. Will test the FD in the next few days and report
the results. I also didn't like the engine being so close to my back when riding.
It was annoying. FYI, I used a very large 56T sprocket on the rear wheel to increase
the drive ratio. The sprocket that came with the kit was too small