Ducati Monster Forum

Moto Board => Tech => Topic started by: dax on September 29, 2008, 12:48:03 PM

Title: is 14t front 42 rear on a S4 too low for gearing?
Post by: dax on September 29, 2008, 12:48:03 PM
i switched out my front sprocket for a 14t a year ago and loved the change but honestly i want a little more low end now.  basically i want to be able to power wheelie in higher gears with less effort.  I mistakenly ordered a 42t rear sprocket and seeing as how stock gearing was only 37t on a 2001 S4, am i getting a setup thats going to be a pain to ride?  I dont mind low gearing but if it comes at the cost of SIGNIFICANTLY lower fuel mileage and lots of top end loss i'd rather not deal with the issues.  I could definately return the 42t if needed and get something a little less radical.  anyone have any experience with this?
Title: Re: is 14t front 42 rear on a S4 too low for gearing?
Post by: Howie on September 29, 2008, 08:29:02 PM
It's up to you.  A close enough (IMO) figure is about 250 RPM drop for each tooth.  If you feel the 42 is too much of a reduction you could move up to a 15 up front and still have more reduction than you do now.  There are some sprocket selectors that calculate for you if you do a search.
Title: Re: is 14t front 42 rear on a S4 too low for gearing?
Post by: Rameses on September 29, 2008, 08:45:06 PM
Dude, I was running a 15/41 setup on mine.

15/42 would've been tolerable, but I wouldn't have chosen it.

For me, 14/42 would be way too far.
Title: Re: is 14t front 42 rear on a S4 too low for gearing?
Post by: Speeddog on September 29, 2008, 11:04:27 PM
If you do a 15/42, you'll have it 6% lower than your current 14/37.

A 14/42 would be *really* low-geared.
Title: Re: is 14t front 42 rear on a S4 too low for gearing?
Post by: Jobu on September 30, 2008, 03:04:51 AM
Quote from: Speeddog on September 29, 2008, 11:04:27 PM
If you do a 15/42, you'll have it 6% lower than your current 14/37.

A 14/42 would be *really* low-geared.

My old 750 was running a 15/45 setup which is exactly the same as a 14/42. 

It was pretty ridiculous on the 750.  I didn't like it at all.  Highway RPM's were very high (only 5 speed gearbox though).  And it topped out at 101 indicated.  It would power wheelie like all hell in first though, which was fun.  But I quickly changed it to a 15/42 (I think) which was much better.

I would think that would be way too low on the S4.  Ducs are geared so tall, that with that setup, your not going to have much difference in the first few gears.  Hell, I could take off with the 750 with a 15/45 setup in 4th (I know because I did it unknowingly once).  A popular gearing is around 15/41 or 14/39 (Stock was 39 in 02).  So, if your looking for a just a little more, I would think a 40 on the rear with the 14 front would be the lowest you could stand.  That will be a 7.5% reduction from a 14/37.
Title: Re: is 14t front 42 rear on a S4 too low for gearing?
Post by: hypurone on September 30, 2008, 06:00:28 AM
Small steps grasshopper. I ended up at a 1 tooth difference from where I really wanted to be (very long story) and it is enough to be noticeable and wish I could get that 1 tooth every ride. Go here if ya like lots of numbers to chew on:

http://www.gearingcommander.com/ (http://www.gearingcommander.com/)
Title: Re: is 14t front 42 rear on a S4 too low for gearing?
Post by: ducpainter on September 30, 2008, 06:04:57 AM
Quote from: hypurone on September 30, 2008, 06:00:28 AM
Small steps grasshopper. I ended up at a 1 tooth difference from where I really wanted to be (very long story) and it is enough to be noticeable and wish I could get that 1 tooth every ride. Go here if ya like lots of numbers to chew on:

http://www.gearingcommander.com/ (http://www.gearingcommander.com/)
If you use the gearing commander site make sure you check the trans ratios against the moto one site.

There are a few errors, but the calculator they have is great.
Title: Re: is 14t front 42 rear on a S4 too low for gearing?
Post by: ♣ McKraut ♣ on September 30, 2008, 06:36:23 AM
i have a 15/42 setup on my supersport 900; i wouldn't want the gearing any shorter.
Title: Re: is 14t front 42 rear on a S4 too low for gearing?
Post by: dax on September 30, 2008, 12:22:55 PM
i think i'll switch back to the 15t up front from what you guys are saying.  i've heard that reduces wear on the chain anyways.  glad i kept that sprocket.  If its unmanagable then hell i'll pony up for a 40 tooth out back or something.  thanks for the help guys
Title: Re: is 14t front 42 rear on a S4 too low for gearing?
Post by: jerryz on October 03, 2008, 09:22:46 PM
I am running 15-43 with PC111 and 116bhp it is great.
Title: Re: is 14t front 42 rear on a S4 too low for gearing?
Post by: Rameses on October 04, 2008, 12:09:36 AM
Quote from: jerryz on October 03, 2008, 09:22:46 PM
116bhp


Please elaborate.
Title: Re: is 14t front 42 rear on a S4 too low for gearing?
Post by: dax on October 06, 2008, 01:25:25 PM
Quote from: jerryz on October 03, 2008, 09:22:46 PM
I am running 15-43 with PC111 and 116bhp it is great.

def would like to hear more about this.

anyways i put the 42 on the back and the 15t on the front and the bike is running fine.  got it on last night and took it for a quick spin with a new chain so i could make sure i didnt screw anything up.  i've only ridden it to work today but so far all i've noticed is the obvious propensity for the wheel to not touch the ground in first.  still second gear doesn't make the front end as light as i thought so i think this is gonna work out just fine.  i'm making a run to boone for the weekend to ride so we'll see how the new sprocket setup works in the mountains.