Ducati Sporting Club

Reply
 
Thread Tools Search this Thread Display Modes
  #1  
Old 21-Dec-2014, 12:13 AM
Ian 748's Avatar
Ian 748 Ian 748 is offline
Registered Forum User
GTL
 
Posts: 428
Join Date: Mar 2004
748 valve clearance Q

Well as Iíve had the old girl a fair while now Iíve decided that itís about time I tackled the servicing myself, and so far so good, Iím really enjoying myself.
Got all the valve clearances measured today and got to thinking. The online workshop manual shows all clearances .03 tighter than the Haynes book, so pretty close but! As both of these guides are a few years old now have Ducati ever changed the recommendations?
Half a day Googling reveals that almost everybody whoís written about it knows no more about it than I do. If anyone genuinely knows Iím all ears.
Cheers Ian
Reply With Quote
  #2  
Old 22-Dec-2014, 07:35 AM
dunlop0_1's Avatar
dunlop0_1 dunlop0_1 is offline
Registered Forum User
Big Twin
 
Posts: 1,564
Join Date: May 2009
I had a 748 road bike and several engines in my 996 race bike. I always set both clearances at 0.10mm or 4 thou. It is more important to set the closer clearance first and then the opener. If you try and do both in one go it just won't work.

Reply With Quote
  #3  
Old 22-Dec-2014, 10:08 PM
Ian 748's Avatar
Ian 748 Ian 748 is offline
Registered Forum User
GTL
 
Posts: 428
Join Date: Mar 2004
.10 is a measurement that comes up often and Iíve no doubt itís widely used and works well. However that reads as out of tolerance with some of the Haynes clearances, both the checking and their adjusting figures. Also with the Ducati figures I have to hand. That is in no way a criticism, just trying to figure out whatís important and what isnít. If you set at .10 how far would you let them wear before reshiming?
The crux of the matter is if I use Haynes checking clearances I am within spec and need do nothing, if I use any other figures I have varying and differing amounts of shims to change depending on which set of tolerances Iím looking at.
Thanks for the reply it all helps me form an understanding.
Reply With Quote
  #4  
Old 23-Dec-2014, 09:32 PM
dunlop0_1's Avatar
dunlop0_1 dunlop0_1 is offline
Registered Forum User
Big Twin
 
Posts: 1,564
Join Date: May 2009
20 thousand miles on the road bike and 3 years racing 3 engines at up to 11k revs almost all the time. Trust me whatever you have read these settings work.
However if you want to be mega anal about it,


All closers - .05-.10mm

Intake -
open .10-.15mm

Exhaust -
open .15-.20mm



Last edited by dunlop0_1 : 23-Dec-2014 at 09:38 PM.
Reply With Quote
  #5  
Old 23-Dec-2014, 11:32 PM
Ian 748's Avatar
Ian 748 Ian 748 is offline
Registered Forum User
GTL
 
Posts: 428
Join Date: Mar 2004
Quote:
Originally Posted by dunlop0_1
However if you want to be mega anal about it,


I canít help myself until I understand
Thank you very much once again, iím sure itís all a lot more interesting when you havenít tackled it before .
Reply With Quote
  #6  
Old 26-Dec-2014, 12:16 PM
dunlop0_1's Avatar
dunlop0_1 dunlop0_1 is offline
Registered Forum User
Big Twin
 
Posts: 1,564
Join Date: May 2009
Something else to consider is how far do you want to go?

Ideally remove the heads and lap all the valves in. This would mean an assembly clearance and then later a checking clearance. You may use new half rings which again means assembly and checking clearances. Even if you re use your half rings they may well settle differently in a new shim therefore requiring another adjustment.

Deciding on what you want to do is harder than the actual job. LOL

Enjoy
Reply With Quote
  #7  
Old 27-Dec-2014, 11:09 PM
Ian 748's Avatar
Ian 748 Ian 748 is offline
Registered Forum User
GTL
 
Posts: 428
Join Date: Mar 2004
Yes indeedÖthe thought had crossed my mind. With only two shims and a persistent tiny oil weep from the cam carrier,or rocker pin cover (canít find it for sure). Iím trying to resist the temptation to find more to do.
Cheers Ian
Reply With Quote
  #8  
Old 28-Dec-2014, 09:50 AM
dunlop0_1's Avatar
dunlop0_1 dunlop0_1 is offline
Registered Forum User
Big Twin
 
Posts: 1,564
Join Date: May 2009
If you are going to pull the cams out then don't forget to inspect the rockers and particularly the openers for the dreaded flake.
Reply With Quote
  #9  
Old 29-Dec-2014, 05:39 PM
Ian 748's Avatar
Ian 748 Ian 748 is offline
Registered Forum User
GTL
 
Posts: 428
Join Date: Mar 2004
Ooo you did have to go and mention rockers didnít you. Just had a peekÖtwo openers and two closers are just starting let go. Two closers and one opener are original and have covered 40,500 miles. The other is a failed replacement that has done either 23 or 12 thousand miles depending when it went in.
Thatíll be my plan for just two shims out the window then, and I all but wished for something else to do, itís my own fault I suppose .
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 03:15 AM.