Ducati.ms - The Ultimate Ducati Forum banner

21 - 40 of 53 Posts

·
Registered
Joined
·
4 Posts
Interesting. Same place I did my engineering undergraduate, along with a year of motorcycle engineering at a German university.

So, the actual company that makes the tool, and remembers their physics, feels the mass need be input, but 'we' don't? I don't get that. I think they'd be surprised too. But, I'll admit, I could be missing something here.

Back at the aforementioned good ol UIUC, I worked quite a bit on the then current hybrid electric vehicle project (about 20 years ago now) We used belts for a fair amount of drive work, and used some frequency guidelines for tuning them. There too, the mass was needed.

Again, no disrespect intended. I said up front that your method will get you close, since belt mass doesn't vary much. But it does some (>5% I've seen on 2V belts over the last 16 years of duc wrenching). I can get well within 10% just by hand, so it's quibbling anyway.

be well.
 

·
Registered
Joined
·
1,031 Posts
The gates unit needs something in its program just to read any thing. If the frequency is know the mass is not important. At least that is how I understood what was said. The measuring device does not know or care how you get to 110Hz. It could be reading from any resonation string, my cello, the ducati timing belt or other belt. Since we have two knowns, its is the correct belt and the correct frequency we need only tune it. Now if it were possible to put the incorrect belt on and tune to 110 Hz. that would be a problem. Am I missing something? This is a quote from Gates.

"The mass contacts are listed in the Sonic Tension Meter Manual that you would receive with the purchase of a new Gates Sonic Tension Meter 507C. If you are trying to determine the frequency that corresponds to a known span tension, you can calculate it using the equation listed in the manual. If you have a known frequency, you can use the meter to measure it without entering in the mass contacts specific to the belt drive. Please note that brand new meters do not have length, mass and width contacts preprogrammed, so you will need to enter in the contacts for at least one belt in order for the meter to function properly."

Hope this helps.
 

·
Registered
Joined
·
806 Posts
Just telling you all a fact. When using the Gates (OEM manufacturer of Ducati timing belts) Hz frequency type belt tension meter you must enter the measured belt mass for each belt type and style you measure.
This is a very logical concern in metrology. The frequency emitted by belts of different mass will not result in the same tension (applied pressure) on the pulleys.
 

·
Registered
Joined
·
1,031 Posts
I believe the gates unit requires this to compute the required frequency which those of of doing it by HZ already have. I also believe on some models of the gates unit you can enter the required frequency directly. At least that is what one of the reps told me. I use my MacBook and frequency counter program. Set them to 110HZ about 1500 miles ago. So far so good.
 

·
Come in Spinner :)
Joined
·
7,658 Posts
This thread is getting too complicated.
The average new belt on the average bike set to an average tension of 110hz will be just fine.
 

·
Registered
Joined
·
82 Posts
Has anyone checked the performance of the Android app (Gstrings) or any other Android/iPhone app against that of the official DDS or Gates tools or even against the old 5mm/6mm allen wrench check? I cannot find the Gates tool for sale, and another sonic belt tester was nearly $1000.

Also, where can I find a copy of the official Ducati tech bulletin regarding the 110 Hz frequency for all belts?
 

·
Registered
Joined
·
82 Posts
You don't set it to 110 Hz, it's supposed to show the frequency when you flick the belt / string.
 

·
Registered
Joined
·
1,031 Posts
I use the exact app for my old android X both for tuning my cello and for setting the belts on my 07 999S. It works great and does not pick up the white noise like the spectra analyser program. I totally agree a frequency is a frequency, but am aware some of the analyzers require certain data to match a belt for it to establish a manufactures requirement. In essence it still measures the frequency. It either does it acoustically as with a mic or the more exact and BTW expensive units use a light beam to measure the occupations / frequency. I see I made a similar comment some time ago.
 

·
Premium Member
Joined
·
4,829 Posts
Has anyone checked the performance of the Android app (Gstrings) or any other Android/iPhone app against that of the official DDS or Gates tools or even against the old 5mm/6mm allen wrench check? I cannot find the Gates tool for sale, and another sonic belt tester was nearly $1000.

Also, where can I find a copy of the official Ducati tech bulletin regarding the 110 Hz frequency for all belts?
I checked the gString against the 5mm allen wrench, that was spot on, 110hz is 110 hz so I just ride and not worry about mass.

believe in the thread below there are more answers

http://www.ducati.ms/forums/80-hall-wisdom/35050-belt-adjustment-questions-answered.html

There are few more threads in each sub-forum on sonic tension and apps, you can easily search them if you are interested.
 

·
Registered
Joined
·
82 Posts
Thanks, I will check out that thread.

Where's the best place to put the Android phone mic to record the belt sound for the vertical and horizontal belts?
 

·
Registered
Joined
·
1,031 Posts
Put the end you talk in to at the mid point on the lower side of HZ belts and back side of the Vert.. Make sure that Cylinder is TDC.
 

·
Registered
Joined
·
42 Posts
Put the end you talk in to at the mid point on the lower side of HZ belts and back side of the Vert.. Make sure that Cylinder is TDC.
That's what I did with my phone and this app - used belts came in at 85 and 87 Hz. I'm comfortable using this app to tension the new belts.

John
 

·
Registered
Joined
·
82 Posts
This is awesome, Android to the rescue again. Now I can tell my friends that my Android phone replaced my GPS nav, and I can use it to maintain my Ducati.
 

·
Premium Member
Joined
·
4,829 Posts
I'm a huge Android fan, better than anything on the market, but that's a whole other thread... I think it's in Chit-Chat :)
 

·
Registered
Joined
·
95 Posts
Quick question... Did you change the settings on the App, mic sensitivity, range, etc... or did you leave it at default?

I'm changing the belts on my 748 and I get a little bit of 58-60 Hz interference. (might be the lights) Does the App pick up 110 Hz clearly.

Thanks,
 

·
Registered
Joined
·
95 Posts
I used the default App settings and was able to get a pretty consistent 105 Hz from each belt at TDC for each cylinder. I purposefully erred to the loose side of the +/- 5Hz.
 

·
Premium Member
Joined
·
106 Posts
You guys are arguing about belt mass but what you probably never considered is: can you measure the belt mass accurately?
 

·
Registered
Joined
·
97 Posts
Belt tension iPhone Apps

I'll sidestep the belt mass argument for a moment, here are some observations from setting belt tension yesterday:

1. Apps that work. I know nothing about music theory, but I tried the following and they were comprehensible, consistent and free:

-Gates Carbon Drive App- straightforward. Probably the easiest to use, but maddeningly difficult to get consistent readings from. For some reason, it won't read over 120Hz.

-insTuner- No idea what it all means, but use the 'chromatic tuner' and FFT spectrum readout. You can actually see the frequencies it is measuring. It often measures the wrong frequency though.

2. Baseline: On the hypermotard, I got a consistent tone (about 97hz) by plucking the upper corner of the fork guard. the carbon fiber on the S model probably resonates better than abs, but whatever you get should be consistent.

3. Mic- I am getting one of those desk mics that plug into the headphone jack. I don't think I could pluck the belt loud enough to get a consistent tone.

4. Technique. I suck at plucking belts, and because of that, now I have no fingerprints left.

5. Gripes- why oh why can't we have a screw adjuster for belt tension?

THe bike did like having snug belts again. Next step, get a mike in close and try again.
 
21 - 40 of 53 Posts
Top