would somebody check my math?

[qko]

Sorry, but I'm not sure I'm doing this right.

I have a Worksman Adaptable trike, an extra 5hp Briggs, and a Comet Torq-a-Verter with a 10 tooth cog.

Top speed would be 40 mph @ 3600 rpm on a 26" wheel - I figure 517 rpm at the wheel - 3600 divided by 517 = 6.96

Is 7:1 ratio reasonable using a torque converter? Do I need a jackshaft for this? Is there something I'm missing?

Thanks in advance

qko

 

[msrfan]

Your Comet is (or represents the same as) a jackshaft, giving a double ratio reduction. 7:1 is a totally reasonable overall drive ratio. That's about what I run on my 5hp Briggs bikes with the top speed just as you predicted. Good luck and provide photos if you can. Should be an interesting build. My pulley sizes are 3.5" to 5" and 3" to 15", for an overall ratio of 7.14:1. So I think you're where you want to be on yours.

 

[qko]

Nice...

thanks again

qko