Yep... That's the one alright.
I agree with you about the gearing, it's just that I often tow a trailer to haul things.
By gearing I was talking about sharing the bicycles geared drive train with the engine.
Look Mom! No left side chain!
I prefer an internal 3-speed back wheel myself.
The chain is always straight and you can use HD single speed chain but this works.
Titan XC50 R Magnum is rated @ 3.25 hp. That's pretty close to DOUBLE the horses!
Now with THAT motor I can gear it up to do 40 - 50 mph, not a problem.
Horsepower has nothing to do with mathematical top speed as you know, that is a set formula by your engines max RPM's, Gear Ratio, and Tire Size.
I would take that DAX 3.25 hp rating with a spoon of salt.
Just like many 2-stroke vendors claim their cheapo 2-stroke 66cc 2.75 hp engines are 80cc and 5-6 hp, I suspect 3.25 hp from what looks to be a stock HS 142F 49cc engine with a new sticker just might be fudged a bit unless they are really building EPA OK'ed engines in the USA.
That would warrant the extra $100 over an HS anyway.
I like the HS 144F-1G 53cc with a couple cheap upgrades myself.
I don't have a dyno for test results, just a lot of hands on experimenting.
Get your valves set right (.04mm intake, .06mm exhaust), replace that restrictive box exhaust with a freer flowing long exhaust, and replace the stock plug with a slightly longer NGK Iridium plug for a bit more compression.
I'll run the 53cc shifter above against any stock 66cc 2-stroke direct drive and kick their butts in every single way possible.
My point is, with gears you change everything.
From dragging a boat anchor up a hill from a dead stop, to going crazy fast with the same machine.
Just a note:
You better have a darn nice bicycle before you start thinking riding 40+ mph. Really man. Besides the bicycle parts taking twice the speed they were designed for, you need to stop as fast want to go.
Hope that helps.
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