14 tooth sprocket YES or NO

[puchika]

The main reason you'd go -1 on the front is because it's inexpensive and +3 on the rear because it's less tension on the chain?  Am I summarizing the posts correctly?

TIA

[BastrdHK]

Pretty much, although the excessive tension theory is some what of a wives tale b/c several  Ducati superbikes came stock with 14t sprockets.  A quality chain will easily handle the tighter radius.

[Cucciolo]

Now that I've tried both 14 and the 15 front sprockets.. I wonder why some say that Ducati only installs the 15 to pass emissions and that the bike was meant to have a 14t... to me the bike feels much better with the 15t and people should be saying it was meant for the 15t instead! 

[bigiain]

Now that I've tried both 14 and the 15 front sprockets.. I wonder why some say that Ducati only installs the 15 to pass emissions and that the bike was meant to have a 14t... to me the bike feels much better with the 15t and people should be saying it was meant for the 15t instead! 

Heh - keep in mind your S4R produces about twice the power (and probably torque) compared to my little 750. It doesn't surprise me too much that the benefits some of us with lower powered bikes get aren't necessarily transferable to you guys with the big 4 valvers :-)

big

[ducatsSF]

I'm switching back to a 15T, losing the top end speed isn't worth the little bit of pep I get going thru the city.  I plan on just staying on the throttle more.  imho [moto]

[silentbob]

Here is a good post from Chris Kelly from TOB.


No, actually, it's still a myth. And it refuses to die because people listen to their own "common sense" rather than actually perform testing. I mean, it's so much easier to be right if there is no objectivity and you never check the possibility you're wrong, yeah? I'm not putting down those who in their own mind have an opinion and belief and choose to use a 15t sprocket as their personal preference. I have issue with those who have to evangelize bullshit and force their opinions down the throats of others. No, actually, I don't have issue with that either. I have issue with it when folks who haven't yet decided for themselves become believers of the True Cult of Fifteen Toothed Sprockets Only or Die!

This myth started on the internet, where people commonly ignore those whose professions are in the field being discussed. Where people with, OMG, actual experience have seen the light -- and it wasn't from the god created for the True Cult of Fifteen Toothed Sprockets Only or Die! religion.



Ok, so I'm a bit cheeky ... I'm getting over the flu from hell and I come back to the Intarwebs to the fresh smell of BS. You all caught me at my weakest.

Maybe rather than do actual work, I'll need to set up a test bed with an electric motor turning two sets of sprockets with a chain. 15/42 on one and 14/39 on the other. Part of it will be to calculate the speed and miles travelled based on the rpm of the system.

Since everyone but me seem to have more scientific research with motorcycle drive chains and are claiming my field experience is not valid, please provide me with the specifications for my test to confirm your findings. Do we want continuous 100 mph for 10,000 miles? 15,000 miles? Which chains for the test? How long should the chain be? How should we handle the theoretical concept of a load? I mean, if the 14 vs 15 tooth count is such the deciding factor, surely it won't matter what the load is, how long the chain is, or other sprocket size, as the contribution of sprocket size is the greatest factor, yes?

Yeah, there's a hint of sarcasm there. Deal. I've got an engineering degree. So a 4 year collidge taught me how to ask more questions. Guess what, I was also trained by the military for 2+ years about troubleshooting theory and practices. Having worked both as a technician and as an engineer, I can appreciate the value of theory (where you think "wow, that's a huge difference, can't see how that chain can last with a 14t sprocket) ... and I can also appreciate the value of experience (where the lab tech or repair tech thinks about how many times they've seen exactly this and roll their eyes as they evaluate the worth in educating the theorist).

IM-not-very-HO, the best test bed are people who use their motorcycles as daily transportation. About 13 years ago, I was a mechanic helping the lowest tier of street riders keep their bikes running. The *first* time they came in with a badly worn chain or sprockets was also the LAST time. Once we helped them understand the difference an o-ring chain and a little care makes, they would double or triple the miles on their chains. Not once have I seen a situation where sprocket size contributed a detectable amount of increased wear. Not once have I seen a situation where re-using a steel sprocket which was not visibly worn contributed ANY increased wear to the system.

I agree with the industrial application mentioned above. When it comes to the equipment that I depend upon for my income ... or depend upon for my liability or worker's comp insurance, yes, please use a maintenance program with a very aggressive schedule. How much does a chain or sprocket cost versus the entire system? How many hours is the equipment run before replacement? What is the comparable distance and speed travelled by industrial use applications that are run 8 to 24 hours a day? 15,000 miles on a motorcycle compares to 250 to 500 hours of actual use. 250 hours assumes a 60mph average speed, so it would make sense to double it. Oh crap, there's common sense... now I'm trying to join the Cult!!

Since I'm treated like the young punk I formerly was, I'll reintroduce my experience: I've been riding and working on my own bikes since 1985. I've worked as a mechanic and as retail in the moto industry since 1993. I have ridden on motorcycles at least 200,000 miles, have at least 6000 miles on the race track, won races, broken down in the middle of nowhere, etc etc. I'm not a know it all and never think I will be, but I try very hard to learn as much as I can. I believe that I have now graduated from "young punk" to just "punk". Once I can graduate past "punk" and make the first step towards "wise", hopefully I'll not care so much about the efforts people make to deceive others in my industry.

The foundation of ducatitech.com and ca-cycleworks.com is the principle of trying to save others from repeating my stupid mistakes and OJT missteps by sharing information that would otherwise be considered insider info. A local motorcycle shop was the motivation for starting out my quest to share knowledge -- I asked a couple of simple questions about my then new-to-me 92 Ducati 900ss. I had worked as a wrench for 3 years and knew every brand had it's unique issues. When they laughed me out of there, I was determined to learn as much as I could and share with as many as I could. Surprisingly similar in spirit to the open source software movement.


To recap, if it makes YOU feel better to replace your sprockets more often than needed or to not change your gearing, that is awesome. I like to know people are happy with their bikes. But please knock off the propaganda, ok? It's ok that someone loves their bike and believes their bike is special. But the bike is the same steel, aluminum, plastic, and rubber as every other motorcycle on the market -- same laws of physics apply.



And in case you didn't guess, I am touched to the core of my being when people make claims 14t sprockets increase chain wear.

[thruxton]

I say it depends ... I feel like I'm reving the piss out of the bike in order to go 80 MPH.  I don't see the need to rev an engine that has more than enough torque to maintain that speed at a lower RPM.

So around the city and in the twisties...I think the 14 is the way to go.  If I were to ride on the highway more, I'd stick with the 15 or even think about a 16.

depends on the monster. my S4Rs, for example, is only ~5K RPM doing 80mph on the freeway. this bike is dyno-tuned and so it runs smooth even if i let it dip to low RPMs but in top gear the engine doesn't feel zippy and fat unless i am doing 90+

i've done every mod you could reasonably do to this bike so i guess this is the final one. i held off bc i didn't like this mod on a previous bike (yamaha 600 i had back in the 90's) and so i have stuck with the stock gearing for the past 2 years. going tomorrow for some new rubber (BT16s) and having the 14 tooth done at last. i'll report my findings 

[corndog67]

From my experience, if you put the best quality chain on the market on your bike, a DID ZVM, it doesn't matter what your gearing is.   It will last a long time.  I've had shitty experiences with both Tsubaki and RK, in my opinion, DID is the best there is.  The last bike I owned, I put the DID ZVM on, it required 1 adjustment before 1000 miles, and didn't require another adjustment for the next 20K, when I sold the bike.  That is with a steel rear sprocket.  Gearing?  Put whatever you want on there.  If you use a less than quality chain, the smaller diameter might make a difference.   

[Itsasickness]

Yes! period, you won't regret it

[hihhs]

It is the best (and cheapest) performance mod out there!

[DarkStaR]

I stayed with the 15t up front, and +1 in the rear.

I don't like the extra chain rub noise some bikes make with the 14t up front.

[thruxton]

... my findings 

geez. why did i wait so long?!?!

as i rode away from the shop this morning i could not hardly tell it had been done. while i was expecting "whoa," it is instead, very subtle.

so it was a long 1.5 hour ride home and i got to know the new gearing well. @ 80mph the tach is about the same @ 5100. the feeling as you twist the wrist, though, is one of immediacy. it's a bit hard to explain but with stock gearing @ 80mph in 6th gear, there was a sort of slack that needed to be taken up before the zoom zoom. no longer. twist the wrist now and it's on!

came upon some slow traffic with lane splitting in 1st. with this i felt a sense of urgency to the bike. it rode easy and smooth but would seem to come up quickly from nothing to 30mph and you want to up shift.

so, overall subtle but perfect. all pro, no con. for those with a S4Rs, it's an easy recommendation. 

[DoubleEagle]

I have a 14 T on my S4Rs which also has a full Termi System , DP ECU and Open Airbox.

The bike is so quick to spin up the rpms.

I am sold on the initial inexpensive mod.

Dolph     

[JasonV]

I'm wondering if I should do this myself with a new 696.  My first bike and I'm a new rider and I live and commute in NYC everyday.  In traffic and in gears 1, 2 and 3, bike feels jumpy on and off the throttle.  I don't know if this is more that I'm a beginner and my shifting can be better or the performance of the bike.  Guy at the dealer mentioned possibly doing the 520 chain/14 T modification but am reading both pros and cons on this thread.  Wondering about the performance from those that did it on a 696. 

[stopintime]

JasonV + possibly others:

It's "impossible" to make a Ducati smooth, our bikes are built to perform under pressure - heavy throttle, high rpm, quick shift a.s.o. That doesn't mean we can't ride smoothly, it just means we don't get a whole lot of help from our bikes.
I know my bike quite well, but in city traffic I constantly feather the clutch and I'm very precise on the throttle.
What really helped me a lot was to tighten the throttle wire to almost no freeplay (not so much it restricts the throttle grip tube, which must have it's built in freeplay)
IMO, the 14t helps a little, but it does not transform Ducatis into something they're not. Which is fine really [moto]