Sports: Re: [DucatiST] Re: Replacing Chain and Sprokets, opinions?

On sprocket ratios, you want to get odd numbers so that you don't get whole number multiples...like a 14:42 is 1:3. A 15:42 will be better at a 1:2.8 ratio. A 15:45 ratio would put you right back at the 1:3 ratio, an undesireable number. The odd ratios spread wear or a kink so that it doesn't hit the same place on the sprockets or on the chain all the time.

Also when possible, keep the countershaft sprocket size as high as you can as in a 15 tooth is better than a 14 tooth which is better than a 13 tooth. The smaller diameter sprockets will cause a tighter radius and a higher angular velocity causing more wear when each link goes around the sprocket, tooth by tooth. If you need to gear down, try to go bigger at the rear sprocket instead of smaller at the rear sprocket, and if possible go bigger at the countershaft sprocket then figure what size you need for the rear sprocket.

Cheers...Hopper

--- On Sun, 9/4/11, srnelson_st2 <srnelson94588@gmail.com> wrote:

From: srnelson_st2 <srnelson94588@gmail.com>
Subject: [DucatiST] Re: Replacing Chain and Sprokets, opinions?
To: st2_owners@yahoogroups.com
Date: Sunday, September 4, 2011, 9:39 AM

It sounds to me like your chain has stretched unevenly. I had the same issue on my ST2 and it behaved like you describe.

I got my chain and sprockets from California Cycleworks and highly recommend them. Chris Kelley doesn't sell anything that isn't top quality and he has very good prices as well.

I don't know if you're going with standard gearing or not. Stock is 15/42 and I found that 15/44 felt best on my ST2. I had previously tried 14/42 for a short while but felt that 15/44 was the best all around gearing for me.

__Scott R. Nelson, Folsom, CA

--- In st2_owners@yahoogroups.com, "jerea99" <ducati@...> wrote:
>
> I noticed a couple of issues riding my 99 ST2(44,000 miles) back
> from Cape May, NJ when we were evacuated for Hurricane Irene.
> In 1st gear the bike was jumping and lunging for the first few
> thousand RPM's. Also when accelerating in higher gears, like when
> entering a hi-way from the entrance ramp, in the higher gears at
> higher RPM's the bike was shaking unusually hard. When I got home
> to Rhode Island, it ultimately came down to the chain, which was
> incredibly loose. A free play of way over 1.09", measured at the
> 1/2 way point of the swing arm. I tightened it up and all problems
> are gone. But the rear sprocket needs to be changed, so front
> sprocket, too and I will also change the chain, even though 16
> links measures within the work shop manual tolerance of just
> over 10".
>
> So, I am asking for your opinions on what to buy and where to buy.
> Thank you in advance.