I recently had a guy come up to me as I was getting ready to fire up my bike. He said "Dude, you should get a 3 speed transmission - they're fast!" I started to explain that gearing determines what rpm you'll be at for a given speed, but can't change your speed unless you're geared badly to begin with. You need more power and/or less drag to go faster He responded by starting to lecture me about his friend with a 3 speed whose bike was now "wicked fast" and that "torque is where speed comes from." He said my 5 speed was adequate, but a 3 speed would make it scream. I put on my goggles as he kept talking, said "nice to meet you", and rode away. It seemed like a conversation that was going to go nowhere... Eamon
I get the sarcasm in your story. I must also agree I am a newbie. And, If you read carefully, I am not talking of doing 100 mph on the bike, just 65, but with a lower stress on the engine, with a 20 inch sprocket. The overdrive gear was just a theoretical question.
65 mph will put a big smile on my face. I have put a short exhaust. A 30 mm carb, 20 tooth sprocket and a more open air filter (undetermined yet) are next on the list. In theroy: The Electra can go to 65 mph easily, just not recommended for cruising at the speed because of the added stress on the engine. However, with a larger gear ratio, same (not more) speed can be achieved with less stress on the engine. Thats why they have these larger sprockets to begin with.
The best way to increase cruising speed, or reduce the stress on the engine at the cruising speeds is to reduce the load the bike must overcome to maintain that speed.And that is done by improving aerodynamics, to reduce wind drag, which is the largest factor of load that the engine must use its power to overcome at those kinds of road speeds.If you do that, then you truly do have less load, and can then use a taller gear without increasing the stress of the engine, because there's less load to overcome, and the bike can accomplish that at a lower engine rpm more easily, thus you don't need to increase the throttle opening any bigger, and you can use that taller gear to get lower rpms at the same throttle opening as before or maybe even less, because you've cut the load by improving your aerodynamics.
Perhaps one of our resident math wizards can prove or disprove this old time wives tale,,"Every seven pounds you shave of the bike and rider combo is equal to a one HP increase."