14t vs 15t sprocket- RPM@ speed - Ducati.ms

kyle_01 · May 17th, 2009, 9:43 pm

just wondering

i run a 14t sprocket and spend most of my time on the expressway in the 70-80mph zone. i'm returning around 30mpg. looking to improve on that a bit and relax the revs a little at speed.

what do you who run a 15t see for rpm @ say 75mph?

thanks for the help.
kyle

Swodi · May 17th, 2009, 10:06 pm

I'm running the stock 15T and seeing around 43 mpg cruising mostly at 75 mph. I have a 30 mile commute, 22 of which is highway and I run around 75 mph.

Your results, of course, will vary.

Hypremotard · May 17th, 2009, 10:11 pm

Quote:

Originally Posted by kyle_01

just wondering

i run a 14t sprocket and spend most of my time on the expressway in the 70-80mph zone. i'm returning around 30mpg. looking to improve on that a bit and relax the revs a little at speed.

what do you who run a 15t see for rpm @ say 75mph?

thanks for the help.
kyle

Mileage depends on bike config. I have the stock gearing - I will keep an eye out and let you know. I understand that the 14t front renders 6th gear pretty useless as the ratio closely matches 5th whcih would account for your high revs.

08hyper · May 17th, 2009, 10:20 pm

I think the biggest difference in mileage is in the ECU, I have the cams ECU & my mileage is in the toilet, I only get 70mi or less

before the light comes on, and my gearing is stock. Aloha Alex

**Da_Bull** · May 17th, 2009, 10:27 pm

Quote:

Originally Posted by 08hyper

I think the biggest difference in mileage is in the ECU, I have the cams ECU & my mileage is in the toilet, I only get 70mi or less

before the light comes on, and my gearing is stock. Aloha Alex

I can say that, in your case, it's not the ECU it's the rider.

08hyper · May 17th, 2009, 10:33 pm

Quote:

Originally Posted by Da_Bull

I can say that, in your case, it's not the ECU it's the rider.

Allright smartass, I'll be seeing you at the track real soon! with my motor of death,

Aloha Alex

Hypremotard · May 17th, 2009, 10:57 pm

Quote:

Originally Posted by Da_Bull

I can say that, in your case, it's not the ECU it's the rider.

I have the 2-1-2 ECU and the light comes on at 75 and I put in 2.6 gallons to fill. What's the average refill when you hit the light? I think I need to run it out of gas to learn where it runs out of gas...... Not too keen on doing it though.

dukepilot · May 17th, 2009, 11:07 pm

Quote:

Originally Posted by 08hyper

I think the biggest difference in mileage is in the ECU, I have the cams ECU & my mileage is in the toilet, I only get 70mi or less

before the light comes on, and my gearing is stock. Aloha Alex

What's your fuel trim set at? I ended up setting mine at -3 and it improved mileage a little. I did add fuel to the curve at mid rpms/throttle openings and also leaned it out higher rpms/75%+ throttle openings. These adjustments were based on a dyno run with a sniffer up the pipe. The air/fuel ratio showed a richer than desired ratio at lower rpms, some leaness in the middle and way rich on top. This is with the cam ECU (stock cams) and Beast R.

I get close to 80miles before the fuel light comes on. A lot depends on how you're riding. If you're WFO all the time, your mileage is always going to suck, regardless of gearing.

Hypremotard · May 17th, 2009, 11:41 pm

Quote:

Originally Posted by dukepilot

What's your fuel trim set at? I ended up setting mine at -3 and it improved mileage a little. I did add fuel to the curve at mid rpms/throttle openings and also leaned it out higher rpms/75%+ throttle openings. These adjustments were based on a dyno run with a sniffer up the pipe. The air/fuel ratio showed a richer than desired ratio at lower rpms, some leaness in the middle and way rich on top. This is with the cam ECU (stock cams) and Beast R.

I get close to 80miles before the fuel light comes on. A lot depends on how you're riding. If you're WFO all the time, your mileage is always going to suck, regardless of gearing.

Define WFO? basically, when the brake is off, the throttle is on. Kind of like a computer 0 - off 1 - on.... I don't quite understand the design of this throttle. You have to turn it so far to be on.... Weird.

08hyper · May 18th, 2009, 9:45 am

Quote:

Originally Posted by dukepilot

What's your fuel trim set at? I ended up setting mine at -3 and it improved mileage a little. I did add fuel to the curve at mid rpms/throttle openings and also leaned it out higher rpms/75%+ throttle openings. These adjustments were based on a dyno run with a sniffer up the pipe. The air/fuel ratio showed a richer than desired ratio at lower rpms, some leaness in the middle and way rich on top. This is with the cam ECU (stock cams) and Beast R.

I get close to 80miles before the fuel light comes on. A lot depends on how you're riding. If you're WFO all the time, your mileage is always going to suck, regardless of gearing.

Sorry Peter, I don't know, I had the dealer set it up, even with the cams, she seems to run a tad rich, but for now thats OK, better rich than sorry,

I'll know better after my dyno runs, (lots of them)

Aloha Alex