Changed the belts on the bike yesterday which went well and wasn't a problem. Only difficulty arose when trying to get the tension set using a guitar app on the Iphone. Couldent get accurate readings and ended up tensioning by the old fashioned method of twisting the long run between thumb and forefinger to a 45 degree angle. I am pretty happy with this in my ignorance....................but are there any experts out there that feel qualified to comment? Am I safe to re assemble everything today. I am also going to change the coolant today, draining down should be easy enough,but is there anything to watch to avoid airlocks when refilling? Thanks.
once you go down the path of guessing............and any set up ( even a guitar app) other than using the correct kit is guessing........then you are in the lap of the gods.....its not just tension of the belt so nothing is over tightened its also about cam timing.....
I tend find all the guitar tuner iphone apps I've tried are a bit flakey even when used for thier intended purpose. Not that helps much.
I thought there was an allen key method also? For the sake of a few quid i would buy a microphone and borrow a laptop if you dont have one. Ive been playing with noise apps and find each app reports a different reading.
Quarter turn is too tight. Allen key method is for two valvers... Correct tension gives about 5-8 mm deflection between the cam pulleys, but I'd only really go on hz readings tbh. Guitar tuning aps are waste of time. Seen a few and tried them against factory tools. No consistency and not even close to correct tension. Only thing I've seen come close was microphone and some free ware on a lap top.
from the horses mouth............ it amazes me that we spend so much on our bikes and yet try to save what amounts to a very small amount on something that is so crutial!!!!!!!!! if it means so much to save a little then by all means remove the parts to give access to the belts......but as for the supply of the belts well you wont get them cheaper than a dealer may pass on to you, and you havnt got to buy the kit to get the job done properly,........that may then also come with a warranty...its a no brainer for me!
Well thanks to everyone for their conrtibution, job done , coolant drained and system flushed,bike back on the road and running .Good test run this evening, and a spin planned for tomorrow
agree 100% with nelly there, allen key method is no good due to curve of covers, I use the VA visual analyser with a microphone in hz with the 10hz range selected
Someone a while ago had a topic which was asking if 4 stroke engines have progressed for the better..... ....the above thread is a perfect example of why they haven't.........ie belts needing a guitar to tension them, or push rods needing a feeler gauge. Next thing will be a trombone to test the air intake vacuum for balancing....... Or drums to test for the correct tyre pressures...... Ducati should have stuck to gear driven cams......after all, the engines are only V twins and don't produce that much bhp, so the change from gears to belts can't have added much.......in fact, I wonder how many engines have been wrecked because of some sort of belt problem as opposed to gear driven cam problems. AL.
I changed/removed the belts on my old ST4 for various reasons (none cambelt related!) at least half a dozen times and have always used the 5mm deflection measurement method (between the pulleys on the top belt run) with no problems, covering over 14,000 miles in the process. In fact Rich at Louigi Moto uses the same method! You'll find that this almost exactly equates to the top of the belt reaching the bottom of the 'ridge' where the cambelt cover locates - using 'moderate' thumb pressure e.g. using just your thumb NOT your arm! Some internet 'wisdom' recommends that you give the vertical cylinder closer to 6mm freeplay to account for the extra expansion due to lower airflow than the horizontal - not sure if this is valid or not seeing as the Desmoquattros are liquid cooled anyway? If you look back at the amount of different 'official' ways that Ducati have introduced to measure cambelt tension over the years my thinking is that so long as it's there or there abouts you should be fine. Just use 'common sense' is my watch word. Being the cynical sod that I am I can't help thinking that Ducati keep inventing these more technical solutions to disuade people from doing their own servicing. On my Monster, I've changed/re-tensioned the belts a dozen times or more over the last 8 years using the then Ducati 'official' 10lb - spring ballance pull method (also shown in the Haynes manual) and never had any issues either. You pays your money and you makes your choice!
