Hi Harry. Nice looking bike. You really stuffed that motor in there. As far as your ratios are concerned it should be easy enough to figure. I think you may do better with around a 10:1 overall drive ratio. Not to fast top speed and easy to take off and go up hills. An 11 tooth sprocket along with a 5'' pulley should get you there. If a 10 is easier to acquire then a slightly smaller pulley should do nicely and maybe fit better. I'm assuming you're using #41 or other 1/2'' pitch chain. The angle is steep so oil level will be improtant. As long as the dipper splashes, you should be okay. You always amaze me how fast you build or modify something. I hope it makes it to the show. I doubt there has ever been one quite like it. It's looks very well built and solid. Don't forget to gusset any suspected weak joints. I'll check your thread often. Thanks for the message, always a pleasure. Dale.