jack shafts & internal gears

I prefer internally-shifted hubs to externally-shifted derailleurs because chain alignment always stays true with internal. With an 8-speed derailleur, you're going to have a lot of chain angle in the lowest and highest gears. With engine power, this will cause increased chain and sprocket wear in those gears. With increased chain and sprocket wear comes a higher chance you get a bad shift and break a tooth or two off a cog set.

You might find this thread interesting to read: http://motorbicycling.com/f48/internal-geared-hubs-whats-good-what-31486.html

I have over 3000 miles on my Sturmey 3-speed, powered by Huasheng, 4G, and a SBP 4-stroke shift kit. So far it's all doing a wonderful job.

The_Aleman said:

I prefer internally-shifted hubs to externally-shifted derailleurs because chain alignment always stays true with internal.

Click to expand...

I completely agree with Aleman, internal gears are much smoother and less hassle.
I am on my 4th NuVinci hub build right now and my personal ride sports one with ~400 miles with a tricked 66cc 2-stroke on it as well.

When it comes to prices the NuVinci is about on par with an 8-speed hub, or if you were lucky and scooped up a few Cadillac Fleetwood bikes that come with the NuVinci and a disc brake for $300 like I did you could just pull it's wheels and put them on whatever you wanted like I did with one ;-}

3 speed internals aren't bad, my bike originally had one and I put a lot of miles on it just fine, I just wanted a little more control.

Derailleurs do work though if they are in Tgood shape and generally you don't need the lowest or highest gears anyway, but the big problem with an 8 speed is how thin the chain is. It doesn't take many under power 'bad shifts' to rip that chain apart and leave you walking.

Though I haven't tried one yet, I would a 5 speed would be good, you could at least use HD 410 for the drive chain.