Rear Tooth sprocket question. Why are some guys going up 4 teeth

[DucatiKev]

Ducati is modest. Claudio isn’t one to brag

 

[Don14R]

The R crank assembly is 1.1 kilos lighter than a S. That’s almost 2.5 pounds. How do you think they accomplished that??? I don’t care what you believe and like I said the thread is about gearing, not engine components or what they are made outta.

I shifted the S I rode well above 13k. Im sure of that. I never hit the limiter and it never stopped pulling. With all the video game crap turned off I did a 2nd gear roll on. It went all the way to the shift light without ever lifting the front tire. So when I left the next light I rolled into it in first gear and got the same result.

Maybe that bike would be fun if you threw some gear at it but it was boring as phük geared that tall. Fast yes. Fun no. I don’t want to break 200 on the street

 

[DucatiKev]

Why is V4R 40k + costs + ti exhaust
Vs my bike is under 30k with the first round of preferred accessories fitted

 

[DucatiKev]

I don’t care what you believe

It doesn’t matter anyway

How about a test ride on V4 vs V4R at your local official Duc sales & service center
Does anyone even ride their Duc or is it just sitting on display looking damn good?

 

[MaverickiB]

The R crank assembly is 1.1 kilos lighter than a S. That’s almost 2.5 pounds. How do you think they accomplished that??? I don’t care what you believe and like I said the thread is about gearing, not engine components or what they are made outta.

I shifted the S I rode well above 13k. Im sure of that. I never hit the limiter and it never stopped pulling. With all the video game crap turned off I did a 2nd gear roll on. It went all the way to the shift light without ever lifting the front tire. So when I left the next light I rolled into it in first gear and got the same result.

Maybe that bike would be fun if you threw some gear at it but it was boring as phük geared that tall. Fast yes. Fun no. I don’t want to break 200 on the street

Which year S did you ride? Apparently the lack of front wheel lift is a product of tuning and geometry on the 20+ models. My 18 V4 absolutely had no issues busting power wheelies from 2nd and 3rd gear. It was easy to hit the straight in low 2nd gear at the track, roll on, and keep the front off the ground all the way through most of 4th on stock gearing.

 

[craig bush]

Which year S did you ride? Apparently the lack of front wheel lift is a product of tuning and geometry on the 20+ models. My 18 V4 absolutely had no issues busting power wheelies from 2nd and 3rd gear...

same with my ‘19 base.

 

[craig bush]

No mention of Titanium Valves or rods anywhere.

What else has changed within the motor?
SS: “We have lightened many components such as the crank, which is 1.1kg lighter than the 1100’s unit, and using titanium con rods instead of the 1100’s steel units, saving 100g each and also titanium intake valves.”

From:

Technical Focus: Ducati Panigale V4 R

How does it make 218bhp & rev to 16,500rpm?

www.bennetts.co.uk

 

[Don14R]

Which year S did you ride?

2018. It didn’t have 500 miles on it yet and was Newport Ducati’s demo bike

 

[Paul G]

Find it hard to accept the idea that changing gearing isn’t noticeable, I went to 15/41 from 15/39 and its night and day. That said you dont need to change it for the street but it’s sure makes it a lot of fun!

 

[DucatiKev]

Find it hard to accept the idea that changing gearing isn’t noticeable, I went to 15/41 from 15/39 and its night and day. That said you dont need to change it for the street but it’s sure makes it a lot of fun!

Night and day as in it only used to wheelie in 1-4 now it wheelies in 1-6?

Do I need an extended swingarm to take advantage of the replacement sprockets

 

[Paul G]

just when you thought you knew everything.......

credit to maximum-suzuki forum ...old baldy:

Here's a link to a simple little Gearing Calculator sheet that I built a while back. It shows the MPH at various RPM and RPM at various MPH for 2 different sprocket setups, so that you can easily compare two different setups - whether you are comparing, say the effects of a 16T/43T sprocket to the stock 15T/43T or anything else like that. Just change the sprockets in the right hand sheet, to compare to the left hand side.

GEARING CALCULATOR

motodyn.com/media/utils/ob-klr-gear-ratios.xls

SPROCKET COMBINATIONS vs WEAR.

Here's a little sheet and a write-up that I put together to show the affects on sprocket and chain WEAR of different combinations of sprockets and chain lengths, if anyone is interested....it shows the various possible sprocket combinations for the KLR, with the required chain lengths, and the simple MPH change for each combo compared to the stock gearing at 70MPH, and the sprocket "distance" for each sprocket and chain combination to make sure the combination fits the bike's chain adjusters, and the suggested best and worst WEAR combinations, above....

motodyn.com/media/utils/ob-klr-chainsprockets-wear.xls

Note#1 - GREEN combinations are good for wear; Red or Orange are not so good.

Note#2 - This is primarily for the STREET and LONG_DISTANCE highway riders, NOT so much for the dirt riders, who will wear sprockets and chains regardless of the choice of sprockets! smile

Before I get into the details of WHY, I'll say that there is 1 particular sprocket combo that is BAD for wear, and a few that are GOOD for wear.

Bad for wear

* 14T / 40 T (front / rear), with the 104 link chain to fit.

The GOOD wear combos are (in tall to short ratio sequence)

* 17T / 39T
* 17T / 41T
* 17T / 43T
* 15T / 39T
* 17T / 45T
* 15T / 41T
* 15T / 43T (no s---...Kawasaki know what they're doing!)
* 15T / 45T

Some key things to know

The sprocket teeth "locate" the chain laterally while it is running. Now, the chain has alternating "inner" link plates that mesh with the sides of the sprocket teeth, and alternating "outer" link plates which do not. The "inner" chain side-plate links wear on the sides of the sprocket teeth.

Each tooth on an EVEN tooth sprocket will always contact either an inside link or an outside link. Each tooth on an ODD tooth sprocket will ALTERNATE between inside and outside links and so spread the wear over the sprocket teeth better. The ODD number sprockets will show less side wear than the EVEN sprockets, but as most OE sprockets are steel, and as side wear is not normally a major issue, this is not a big deal.

Kawasaki chose the 15T (odd) front sprocket and the 43T (odd) rear sprocket to mate with the standard 106 (EVEN) link chain.

So...RULE #1, for best SIDE wear, always choose sprockets (front and back) with an ODD number of teeth, regardless of the length of chain.

Now, while the SIDE wear may be more important for softer alloy sprockets than strong steel sprockets, it gets more important to look at the teeth and roller FACE wear.

Here, it gets a bit more complicated, because there is a "hunting" gear factor involved, where one wants to ensure that the front sprocket does not "see" the same specific chain link pin on a frequent basis. (The same applies to the REAR sprocket, but we need to look at them separately)

Consider the front sprocket. If the same sprocket tooth "sees" the same chain link over and over and over again at a high frequency, then that tooth-link can cause wear to occur if there is anything not 100% in the manufacture of that specific tooth or that specific link. The one will start to wear the other.

On the other hand, if that tooth "sees" other chain links and not that one same link over and over again, then the wear is evenly spread over the whole chain, and similarly, if there is any issue with one particular link of a chain, and it does not "see" the same tooth over and over, then that wear is spread evenly over the sprocket teeth.

So, one wants to ensure that the front sprocket teeth "see" different chain links as much as possible, and the same for the rear sprocket.

To calculate this, one must take each sprocket at a time and compare it to the number of chain links. It is necessary to reduce the sprocket teeth and the chain links down into their PRIME NUMBER factors, as follows.

14T sprocket = (7x2)

where 7 and 2 are the prime number factors that multiply to 14 (as both 7 and 2 are prime numbers)

Similarly, for a 15T sprocket, the prime factors are (5x3)
and for a 16T sprocket, the prime factors are (2x2x2x2)
and for a 17T sprocket, the prime factors are (17x1)

Doing various lengths of chain the same way, we see

104L is (13x2x2x2) Note: 2 links shorter than stock for some combos
106L is (53x2) - the stock length chain
108L is (3x3x3x2x2) Note: links longer than stock for some combos

Now, we can see which front sprockets work with which chain lengths.

In order to determine the number of rotations of the chain before it sees the same sprocket tooth, and to determine the number of rotations of the sprocket to see the same chain link, one must eliminate the SIMILAR PRIME FACTORS from both the sprocket and the chain factors.

Let's look at the stock 15T and the stock 106L chain...

15T (5x3) and 106L (53x2)

Looking at the prime factors above, you see there are NO factors in common between the front sprocket and the chain, so the chain will rotate 15 times before it sees the same sprocket tooth, and the sprocket will rotate 106 times before it sees the same chain link.

This is a great combination for wear (Kawasaki know what they're doing!)

Let's look at the 14T sprocket against the stock 106L chain

14T (7x2) and 106L (53x2)

Here, you see that there is a common prime factor (2), which we eliminate from both the sprocket and chain, and this results in the situation where the chain will rotate only 7 times before it sees the same sprocket tooth, and the sprocket will rotate 53 times before it sees the same chain link.

This is much less favorable than the stock 15T, for wear.

Now, we can do the same for the REAR sprockets against the chain

40T (5x2x2x2)
41T (41x1) - a nice prime number!
42T (7x3x2)
43T (43x1) - a nice prime number!
44T (11x2x2)
45T (5x3x3)

So, let's take a look at the stock 43T with the stock 106L chain

43T (43x1) and 106L (53x2)

Again, you see that there are NO common prime factors between the 43T sprocket and the 106L chain, so the chain will rotate 43 times before it sees the same sprocket tooth rear sprocket while the sprocket will rotate 106 times before it sees the same chain link.

Again, a very good combination by Kawasaki, for wear.
Kawasaki have chosen very good combinations of front sprocket to chain and rear sprocket to chain for teeth face wear, and also chosen very good sprockets for side wear (odd teeth).

Let's look at a BAD combination, (the 14T and 40T with the necessary 104L chain to fit the bike)

14T (7x2) and 104L (13x2x2x2)
40T (5x2x2x2) and 104L (13x2x2x2)

Here, you see that for the front sprocket, the common factor (2) is eliminated and so the chain will rotate 7 times before it sees the same sprocket tooth while the front sprocket will rotate 52 times before it sees the same chain link.

The rear sprocket is bad with this combo too...

You see that the common factors are (2x2x2) which are eliminated and so the chain will rotate only 5 times before it sees the same rear sprocket tooth while the rear sprocket will rotate only 13 times before it sees the same chain link.

 

[Don14R]

He’s right about the chain making better contact with odd sprocket numbers and it does make a difference (especially with alum rear) but come on man...

When I am changing gearing it is because I am trying to change the way the bike performs

Could care less about a certain tooth touching this link more often than that link of the chain

Guess it all goes back to what are you trying to accomplish?

With some models going thru piston rings and a clutch every 2000 miles how long a $200 chain lasts does not concern me

 

[Paul G]

yes but think of all the Ductista youll impress with your “prime” setup. Anyway whats the best oil?

 

[Don14R]

Ha. Oil is like gearing

Personal experience/preference

Git yer popcorn

 

[DucatiKev]

popcorn ready.
CASTLE_ROCK

 

[Vbreeze]

BWAAhahaahaa aaaa! That's a good one.
1 kilo weight savings in $10k in parts, or skips donuts.

View attachment 35392

 

[Brooklyn v4]

BWAAhahaahaa aaaa! That's a good one.
1 kilo weight savings in $10k in parts, or skips donuts.

But the donuts are sooo good

 

[Don14R]

1 kilo weight savings in $10k in parts

That’s not really how that works

Ya can’t just say oh the bike weighs 2.2 pounds less now, bfd

Every pound lost “below the suspension” equals almost 10 pounds above

So while maybe ti exhaust or a magnesium axle adjuster are not that big of a deal to everyone - wheels, carriers, chains and stuff like that very well could be

Those concerned with performance that is...

 

[DucatiKev]

Every pound lost “below the suspension” equals almost 10 pounds above

Could the impact of extra weight increase non linearly / exponentially for every unit of height added?
Let’s see the science

 

[Don14R]

Below the suspension is relating to stuff that spins

Has nothing to do with how far off the ground it is

But yeah buddy, when trying to make something accelerate the lower the center of gravity is the better

Same for turning when your building a car

How does center of gravity effect a bike in a turn tho? I have no idea

Google it!