Well I've been quite open minded about all the new bike innovations except titanium and carbon fiber cause I'm cheap like that.....

so this season figured on trying the 25/9 cassette sprocket setup for the all purpose bike.

At first the chain felt rubbery while pedaling which it seems would be a result of the extra torque created by the tiny front sprocket. that's ok i guess.

and I've continued to be optimistic, but I'm not convinced this setup has a use outside a ramp park.

Seems very creaky and causes the chain to jump around a bit, even under exactly correct sprocket alignment and proper chain tension adjustment.

Anyone else have pro's and con's of this tiny sprocket business?

Pro's? The bike companies sell more sprockets and cassette hubs, 'cause ya gotta rock the 25-9 to fit in.
Con's? Blowing up your cassette hub, taking it to be repaired, waiting for them to get your specialty parts to fix it, when you could have just thrown on another freewheel for under $20 and kept riding (if your freewheel had even failed in the first place......).
BTW, I'm rolling with a 36-13 and it's just fine.

good insights.

Looked over the drive train tonight after quite a bit of riding and discussed the setup with an oldschool riding buddy.

the chain is thrashed. will try one of those heavy chains next.

the front sprocket teeth are getting sharp and that was a new sprocket this spring.

so when the cassette goes bad, the hub is gone and i'll switch back to a large front sprocket.

It seems with so much torque the sideways pull would be really high which will surely cause the bearings to stress and wear out faster.

Everything about the setup says poorly thought out engineering, unless someone has some insights about this I'm not aware of.

I had some slight sarcasm in my post, but it's all true. The advantages for park/street are: 1. Lighter 2. no more smashed chainrings. It does add a ton more expense to a bike, and in my shop experience, is less durable.

25/9 is a great gear if you are never going to sprint on it... reason being the pressure on the chain is way harder all the time because of the smaller gears. every time you are cranking around your bearings in your hub are getting worn much faster and the gear/chain are under far more stress than a typical gear setup. I dont advise anyone racing to go that low not even close to it. I run a 30-11 on my street bike and it works well, I could go into all the dynamics of a 25/9 or even 22/8 if your that crazy but I think you get the point...

....when my race bike was stolen in Guthrie earlier this year I tried to race my park bike. 25/9 gears. not a chance! Felt like it was never going to get out of the gate! Only thing its good for, in my case, is not clipping the coping dropping in on a ramp or bowl! ....I one guy at the local track give me hard time about it....said i knew your bike was stolen..but couldn't you afford a full sprocket on that new one! hahaha

"2T's"

i'll be running a 28:11 on the park bike, a 36:16 on the 24" cruiser which will get me to work and back and a 33:13 on my 3rd bike.

I'm with Nick on this one. The biggest stress point is the Hub. With a 16t freewheel, all of the pressure is spread out over 5-7 teeth that are in contact with the chain. With a 9t or even an 8t you have that same pressure thats only pulling on 2-3 teeth. I recently switched from 25-9 back to 30-11 and like it so much better. With 25-9 I was breaking chains about every other week at the park.

Just my .02

Jeff