Fifty Plus (50+) - New bike question

I'm a 58 year old male, ride my bike to work in the summer (live in Maine) 10 miles each way.....I ride a 7 year old Kona Hahanna race light.....been looking at a Specialized Sirrus Sport and would like to have any thoughts on Dynamic Runabout (shaft drive). Thanks Mike

Shaft drives trade off messing with a chain for efficiency in converting your pedal pressure into momentum. Usually they run about 70% efficiency vs 98% for chains. Chains can be cleaned in 10 minutes every 250 miles. Which is more important to you? Most say speed over cleaner.

I'm a 58 year old male, ride my bike to work in the summer (live in Maine) 10 miles each way.....I ride a 7 year old Kona Hahanna race light.....been looking at a Specialized Sirrus Sport and would like to have any thoughts on Dynamic Runabout (shaft drive). Thanks Mike

Nothing wrong with a 7 year old Kona as my Now 12 year old Explosif keeps reminding me when I dig it out occasionally.

Well Thanks, your not the first to tell me to just keep the Kona and save the money. Interesting that I can't find anyone that has or likes the shaft drive bike......how are they staying in the game?

Sussex (which makes shaft drives, and i think developed the one Specialized uses) claims a power loss of "less than 1 percent" vs. "up to 2 percent" for chains. I have no idea if that's true, but 70 percent efficiency sounds very low--I can't figure out where 30 percent of the power would be going, if it's not reaching the wheel. They also claim lower maintenance, no dirt or grease, greater reliability, easier assembly and less noise than a chain drive, but none of those things is a big enough problem on my bikes that I'd change for their sake alone. Gear ratios are limited compared to chains and derailleurs, but there should be a wide enough range for ordinary riding. Their big claim seems to be "smoother operation" vs. the "rough" power transmission with a chain. That may be true on some level, as the links run over the gears, but I've never felt it.
Check it out: http://www.sussex.com.tw/se1.htm
Just based on the little I know now, I'd consider shaft drive if I were commuting, in office clothes, regularly. With that and fenders, you'd avoid most of the dirt and crud that gets on you now. For the kind of casual or training riding that makes up 90+ percent of my cycling, though, I wouldn't pay extra for it.

Shaft drive is suitable for a short trip in business clothes (eg making a rail connection). For a 10(x2) mile commute you want the most efficient ride possible. A Sirrus is a good bike to use. The flat bar is no real handicap over these distances but on longer day trips you may want alt hand holds.

I can't find anyone that has or likes the shaft drive bike......how are they staying in the game?


Man, it's so hard to tell where the buying market is headed. If you had told me in 1972 that road bike would be hard to find in local shops in less than 10 years, I wouldn't have believed you. But, along comes Armstrong and the market just shifts gears almost overnight. I'd be surprised if they'll stay in the game for very long.