Ducati Sporting Club

Reply
 
Thread Tools Search this Thread Display Modes
  #1  
Old 21-Jan-2006, 11:34 PM
Carbon749's Avatar
Carbon749 Carbon749 is offline
Registered Forum User
Big Twin
 
Posts: 1,957
Join Date: Mar 2005
Mood: I own a flame thrower
749r v\'s 749s - gearing differences

Hi,

I may be being a numpty and there may be a simple answer, but, according to ducati web site the new 749r has a 15 tooth front and 35 tooth rear, whilst the 749s has a 14 tooth front and a 38 tooth rear.

Any idea why the difference ?

I know that on the 9** style bikes that have 15 tooth front sprockets a quick and easy mod is to fit the 748 14 tooth front sprocket .... is the same case on the 749r ?

Has any one with a 749R played around with their gearing ?
Reply With Quote
  #2  
Old 23-Jan-2006, 04:30 PM
Carbon749's Avatar
Carbon749 Carbon749 is offline
Registered Forum User
Big Twin
 
Posts: 1,957
Join Date: Mar 2005
Mood: I own a flame thrower
boing
Reply With Quote
  #3  
Old 23-Jan-2006, 04:36 PM
Twinfan's Avatar
Twinfan Twinfan is offline
Registered Forum User
Big Twin
 
Posts: 1,774
Join Date: May 2004
Mood: Proud to own a Ducati :0)
15/35 and 14/38 will give very similar overall gearing. As to why they're set up that way I have no idea.

I would think going to 14/35 would be a good thing, and you could use the standard chain. Shazaam gave a chart on here a while back with ideal gearing for each Duke. You might want to do a search and dig it out...
Reply With Quote
  #4  
Old 23-Jan-2006, 04:39 PM
Twinfan's Avatar
Twinfan Twinfan is offline
Registered Forum User
Big Twin
 
Posts: 1,774
Join Date: May 2004
Mood: Proud to own a Ducati :0)
Found it:


Last edited by Shazaam! : 08-Feb-2009 at 12:14 AM.
Reply With Quote
  #5  
Old 23-Jan-2006, 05:12 PM
pedro's Avatar
pedro pedro is offline
Registered Forum User
Big Twin
 
Posts: 1,253
Join Date: Aug 2003
Mood: r
ive gone 14t at the front, very happy with
Reply With Quote
  #6  
Old 23-Jan-2006, 05:27 PM
Ducnow Ducnow is offline
Registered Forum User
888 at Last !!!
 
Posts: 960
Join Date: Feb 2005
Quote:
Originally posted by Twinfan
15/35 and 14/38 will give very similar overall gearing. As to why they're set up that way I have no idea.

Sorry, but if you want a closer gearing shouldn't you go a tooth less on the front or add more teeth to the rear???
And that would mean that 15/35 is wayyyyyyyyyyy taller than 14/38, right??
I mean, if it was 14/35 vs 15/38, then it would be more balanced, right???

Now...... how come the 749R have such tall gearing
Reply With Quote
  #7  
Old 23-Jan-2006, 05:31 PM
JPM's Avatar
JPM JPM is offline
Registered Forum User
BSB Star
 
Posts: 5,686
Join Date: Jun 2001
Mood: Soon my pet, soon
Probably the box.... it'll be a tall first/close ratio box in the R over the other models I'm guessing
Reply With Quote
  #8  
Old 23-Jan-2006, 05:47 PM
Ducnow Ducnow is offline
Registered Forum User
888 at Last !!!
 
Posts: 960
Join Date: Feb 2005
Quote:
Originally posted by JPM
Probably the box.... it'll be a tall first/close ratio box in the R over the other models I'm guessing

Maybe that's it.
Anyway........ i didn't expect such a big difference in gearing.....
Reply With Quote
  #9  
Old 23-Jan-2006, 05:56 PM
electricsheep electricsheep is offline
Registered Forum User
Big Twin
 
Posts: 1,037
Join Date: May 2003
Mood: Diet
it is because the 749R has a different primary drive ratio, therefore it needs a different final drice ratio (chain and sprockets)
Reply With Quote
  #10  
Old 23-Jan-2006, 05:59 PM
Shazaam!'s Avatar
DSC Member Shazaam! Shazaam! is offline
DSC Club Member
Big Twin
 
Posts: 1,167
Join Date: Nov 2001
Any final drive ratio represents a trade-off between acceleration and gear range. The lower the ratio, the quicker the acceleration and the narrower the range of speed for any one gear. Consequently, a lower final-drive ratio means that while the bike scats aggressively in any gear, it requires a more shifting because the gear range is so narrow. Add to that a closely-spaced set of transmission gears and you have a bike that requires more fiddling with gear selection to stay on the torque curve.

The stronger 749R engine will give better acceleration in any gear so it need less help from the gear ratio.
Reply With Quote
Reply
  
Thread Tools Search this Thread
Search this Thread:

Advanced Search
Display Modes
Postbit Selector
Switch to Vertical postbit Use Vertical Postbit

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

vB code is On
Smilies are On
[IMG] code is On
HTML code is Off


Recent Posts - Contact Us - DSC Home - Archive - Top
Powered by vBulletin 3.5.4 - Copyright © 2000 - 2017, Jelsoft Enterprises Ltd. - © Ducati Sporting Club - All times are GMT +1. The time now is 03:56 PM.