TOPIC:

bl_francis wrote: So...Thanks again guys. You were right. I talked to Rob at Z1 and he was super helpful. I was going to go with 18/49 on the 530 chain but they were out of the 18 tooth front sprocket like some of you said. He though maybe a 16/44 but said he didn't like to have such a small sprocket on the front.

We ended up going with a 630 chain with 15/42 and 98 link chain. He said it will put my revs from 4000 to 3900 but I don't usually ride that fast anyway.

Thanks again fo all of your help and expertise guys.

15/42 is the wrong direction. (the stock 630 setup is 15/41 and I know this for a fact). That's a ratio of 2.8:1. This will INCREASE your RPM at a given speed in a given gear over the stock setup (slightly).

jackleberry wrote:

bl_francis wrote: So...Thanks again guys. You were right. I talked to Rob at Z1 and he was super helpful. I was going to go with 18/49 on the 530 chain but they were out of the 18 tooth front sprocket like some of you said. He though maybe a 16/44 but said he didn't like to have such a small sprocket on the front.

We ended up going with a 630 chain with 15/42 and 98 link chain. He said it will put my revs from 4000 to 3900 but I don't usually ride that fast anyway.

Thanks again fo all of your help and expertise guys.

15/42 is the wrong direction. (the stock 630 setup is 15/41 and I know this for a fact). That's a ratio of 2.8:1. This will INCREASE your RPM at a given speed in a given gear over the stock setup (slightly).

This is absolutely true. Someone at Z1E is mixed up - I would stop the buy until you figure out the correct sprocket sizes. Ed

A 17T 530 front sprocket is very close in size to your stock 15T 630 sprocket - then you just need to pick a rear sprocket size to get the final drive ratio you want.

As you say your stock setup (630) is 15/41 = 2.73:1

The following 530 combinations will work for your purpose:

17/42 = 2.47:1
17/41 = 2.41:1
17/40 = 2.35:1

I run a 17/42 530 setup on my GPz 1100 - seriously contemplating changing it to 17/40.

Edit: Btw, JT's online catalogue is a great resource though it does take some searching to find what you need:

www.jtsprockets.com/catalogue

Just a little bit of extra info I got a Vortex 3509-18 18T 530 front sprocket in the mail today. It does not have the boss on it (unlike the photos of it all over ebay/amazon seem to imply). Could have gotten a similar sprocket from JT sprockets for $7 less... Gambled on the Vortex having the boss. It's not a total loss, but I am going to have to buy some spacers for it.

I'm sticking with my 16 tooth and 35 tooth. At 4000 I'm at 70. 15 tooth I'm close to 5000 RPM at 70. I wouldn't listen to a salesman. Chaparral has a 92 link 630 chain to go with it .$136. Free shipping on orders over $100.
Steve

Why change it? I don't think you will notice a dramatic difference. Maybe better on gas some but diminished power bands. I like mine the way it is. Punch it out to 1075. Maybe then it would be worth it.

My bad. I wrote down 15/42 but it is actually 15/40 they're sending me.

Steve, I think you should ride along with a modern car to check that speed at 4000rpm.

I can tell by the sound. My speedo and Tach were all over the place. When I went by one of those speed signs, I was at 60 and 3500 RPM. Might be off a couple one way or the other, still what I thought it would be. Goes from 60 to 45 in two blocks. Going by sound and now, I'm at 45 in third gear. Could follow my daughter and when she gets to 55, she can wave, at 70 again. I think these gauges are very close.
Steve

Oh and besides, the KZP speedo's are supposed to be calibrated. If they weren't so ugly, I would have put one on my bike.

bl_francis wrote: My bad. I wrote down 15/42 but it is actually 15/40 they're sending me.

Ah OK. That's 2.66:1. I can't really feel the difference between 2.73:1 and 2.47:1 myself and your new ratio will fall right in the middle of that range.

As an aside, I just got 49MPG on a trip in the mountains on my P16 with the 2.20:1 ratio 630 setup (stock everything else).. A personal record

Whew!