The engine is from a Multistrada 1100DS, and it lives in my Bimota. In September of 2013 I installed a set of Exactfit belts that Cal Cycleworks supplies. When I did the instal I checked the tension they had and used the same for the new ones. A few days ago I rented a harmonic do-hicky from Ducati tool rental. The device was rather difficult to get reading with, but I was able to get a reading of 110 hz give or take a couple. They felt quite tight compared to what I had set them at.
Then I looked up the specs in the factory shop manual and they spec the 1100s motor at 140hz. The book says to tighten used belts to 140 if they are down to 70, so there seems to be a pretty broad range.
Now my bike has an aluminum fuel tank, so engine noise is transmitted pretty well to the rider. after tensioning the belts to 110 there is quite a bit more engine noise coming up.
I am wondering what the experience has been for others with this motor. This one has a wet clutch so there is less background noise to mask other engine noises!
I could not get that particular tool to work with any degree of consistency, especially on the vertical cylinder. I used the Gates belt app on my Android. I have better luck with that than the guitar tuners.
https://play.google.com/store/apps/details?id=com.gates.carbondrivecalculator
The manual is probably wrong, I would go with California Cycleworks 110 hz.
Check them about in about 600 miles.
Is it wise to adjust belt tension after they are warm or cold?
Quote from: jduke on May 01, 2015, 06:04:22 AM
The manual is probably wrong, I would go with California Cycleworks 110 hz.
Check them about in about 600 miles.
Wot he said. ^
Quote from: memper on May 01, 2015, 06:07:34 AM
Is it wise to adjust belt tension after they are warm or cold?
Belt tension is set cold.
Quote from: oldndumb on May 01, 2015, 06:10:31 AM
Wot he said. ^
Ditto...if you set them at 140 you'll destroy tensioner or idler bearings.
Well, I set them cold, at 110hz, according to the Ducatitool tool, and double checked with the Gates, and it showed 60hz which I know wasn't right as the belts seem quite tight.
The factory does specify 140 for this engine only.
The thing that concerns me is the increase in mechanical noise that I'm hearing.
Quote from: SpikeC on May 01, 2015, 07:21:52 AM
Well, I set them cold, at 110hz, according to the Ducatitool tool, and double checked with the Gates, and it showed 60hz which I know wasn't right as the belts seem quite tight.
The factory does specify 140 for this engine only.
The thing that concerns me is the increase in mechanical noise that I'm hearing.
The factory changed the spec. 140 is wrong.
It's the bearings complaining. Check the bearings.
You should check the belts hot just to see how tight they really get. It's amazing how much the tension increases. You might be able to back off on the tension when cold to quiet things down.
Since your belts are now "used", set them between 100Hz~110Hz +-5Hz . . .This is from my OEM manual, updated Jan15 . . .for 2V engines, no matter displacement.
I had a screen shot of it, but, it was on the damaged laptop, sorry bout not having a pic
Thanks for all the feedback, guys! Since the book says to tighten them up when they get down to 70hz a little loose does not seem to be a problem! Too bad that the unit that desmotool rents does not register that low. I think I had to get the belts up to nearly 100 to get it to register at all.
Quote from: DarkMonster620 on May 01, 2015, 07:56:07 AM
Since your belts are now "used", set them between 100Hz~110Hz +-5Hz . . .This is from my OEM manual, updated Jan15 . . .for 2V engines, no matter displacement.
I had a screen shot of it, but, it was on the damaged laptop, sorry bout not having a pic
They must want to sell tensioner bearings if they're using the same spec on all 2V motors.
Quote from: SpikeC on May 01, 2015, 09:21:26 AM
Thanks for all the feedback, guys! Since the book says to tighten them up when they get down to 70hz a little loose does not seem to be a problem! Too bad that the unit that desmotool rents does not register that low. I think I had to get the belts up to nearly 100 to get it to register at all.
No indication that this is the case in your instance, but getting a reading can be a function of the "twang" technique. In my case, I can go through a series of no/low readings to the point of frustration, only to then find the correct technique and get repeatable readings without knowing what I had done differently.
I can't help but feel that measuring the roller gap is better than checking the frequency, unless you are using the factory tool.
Quote from: ducpainter on May 01, 2015, 09:28:00 AM
They must want to sell tensioner bearings if they're using the same spec on all 2V motors.
according to them these new values DIMINISH the wear on said components . . .
Quote from: DarkMonster620 on May 01, 2015, 10:28:29 AM
according to them these new values DIMINISH the wear on said components . . .
You know how they lie. [bang] [bang] [bang] [laugh]
According to them the belts on my old 900 should be the same frequency?
Quote from: oldndumb on May 01, 2015, 09:56:41 AM
No indication that this is the case in your instance, but getting a reading can be a function of the "twang" technique. In my case, I can go through a series of no/low readings to the point of frustration, only to then find the correct technique and get repeatable readings without knowing what I had done differently.
I can't help but feel that measuring the roller gap is better than checking the frequency, unless you are using the factory tool.
The tool they use on the assembly line is optical and has a built in twanger
Quote from: ducpainter on May 01, 2015, 10:37:17 AM
.....
The tool they use on the assembly line is optical and has a built in twanger
Yep, a Friggin Magic Twanger, better known as an FMT to be precise. ;) The dealers use a similar, if not the same, set up.
Which is why I have always been suspicious of audio tuners, but admire the fact that our belts persevere.....most of the time. :)
Quote from: oldndumb on May 01, 2015, 11:19:43 AM
Yep, a Friggin Magic Twanger, better known as an FMT to be precise. ;) The dealers use a similar, if not the same, set up.
Which is why I have always been suspicious of audio tuners, but admire the fact that our belts persevere.....most of the time. :)
AFAIK the dealers have an optical tool, but whack it by hand.
Needless to say two different tech will get different results.
yes dp . . .
So then why not switch back to the ol' allen key method? Seems the fancy dohickey is hard to get repeatable results, no?
I use the OEM and the MotoReva units . . . Usually within 7Hz at the same point of measurment... and use the 5mm allen to "check"
OK, I went for a little ride today and did an oil change. While I was at it I pulled the belt covers and there was less than a mm of clearance twixt the roller and belt, so I increased it to 4mm. After I get the oil back in I shall see how she sounds, but I dint think that I will be bothering with the "pluck your magic twanger, foggy"!
Quote from: SpikeC on May 01, 2015, 04:29:22 PM
........ "pluck your magic twanger, foggy"!
https://www.youtube.com/watch?v=G6a3fck0NBI (https://www.youtube.com/watch?v=G6a3fck0NBI)
Hahahaha!
Butt serially, after I buttoned up the oil change and started it up it sounds just as happy as can be!
If now all models are set the same, then the 5mm/6mm allen key method can be used on the 1100/1000 models? Correct? Or is it 5/6mm for 900/750s and 4/5mm on 1000/1100s? I know someone who does the litre+ bikes with 4/5mm.
In the end, if theyre not loose enough to slip and not tight enough to strain the bearings then youre ok. I mean how many bikes are running with perfectly tensioned belts.
Quote from: koko64 on May 02, 2015, 01:50:31 PM
.....
I mean how many bikes are running with perfectly tensioned belts.
My thoughts exactly. :)
Quote from: koko64 on May 02, 2015, 01:50:31 PM
I mean how many bikes are running with perfectly tensioned belts.
Mine is! Because I said so!
Quote from: koko64 on May 02, 2015, 01:50:31 PM
In the end, if theyre not loose enough to slip and not tight enough to strain the bearings then youre ok. I mean how many bikes are running with perfectly tensioned belts.
Everyone that has them adjusted so they don't jump or make the bearings noisy. ;D
Considering the bearing collapse issues caused by the over tight incorrect oem spec, it's been the "common sense" spec all along. ;)
The 5 mm allen key is way too loose for the 1000/1100 motors. Your bike will run better with the tighter belt. The sonic method works if you have the correct tool.
I have them set to a very snug 4mm. The engine sounds just dandy!
When I took the original belts off in November of '13 a 5mm just barely fit, and I had no idea how long they had been in there, the motor is an '07 and it had 6k miles on it.
I knew I had taken a screen shot of the Ducati Web educational video regarding belts . . .the date is April 2014
(https://farm8.staticflickr.com/7759/17395016205_50cbd65a23_z.jpg) (https://flic.kr/p/sv91hv)vertical cyl 2v (https://flic.kr/p/sv91hv)
(https://farm8.staticflickr.com/7796/16772495504_1a6a13ee3c_z.jpg) (https://flic.kr/p/ry8qyY)hor cyl 2v (https://flic.kr/p/ry8qyY)
Sorry we are late to this thread, but I thought I'd share with you all what Chris at Cycleworks says about tension in general and with our Exactfit belts.
"The Ducati manuals that say 140 hz were printed incorrectly. The dealers were told all belts should be tightened to 110 hz. If you wish to have the same amount of force pulling between the sprockets with our belt as the OEM belts, use 99 hz."
:D