- Mar 19, 2018
OK. I am a little confused. Currently I have a 10t engine sprocket which leads to a 10t jackshaft input sprocket. The jackshaft output sprocket is about 10t (not yet installed in the video) and this leads to a standard 40t sprocket on the crankset [pedals]. Isn't this normal. Like if i set my derailleur at a 1:1 gear ratio to the crankset, this would be equivlent to if i had no jackshaft at all as if i just mounted a 40tooth on the rear wheel. What do i need to change. Plus i cant open this calc. msi file. BTW I couldn't find any large gears that are compatible with the engine sprocket except those replacement engine sprocket gears which is what i used. If you have a link let me know.You may want a larger input gear on your jackshaft to get a higher gear reduction before your pedals. Most folks look for around 40:1. If below 30:1 you won't be able to help pedal other than just off the line for a few feet. Here is a link to a gear ratio calculator one of our members made. Remember to have your first reduction for your engine set to 20:82 then work from your 10 tooth output to the jackshaft input for the second, then jackshaft output to pedal chainring. You can then work out your chainring to rear wheel, if using multi-speed then you can figure out your 1st gear and last gear speeds at specific rpms. Have fun, looks like you are on home stretch.
PS: stop trolling yourself .
QUICKY: The engine pistons rotates at 5000rpm but you have to multiply it by 20/82 which means the actual 10t engine sprocket is 1200rpm????