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[Snafuperman]

Does a Tension Tester (an example of the type is shown here) come with the bike?  I'm sure it doesn't but thought I'd check . . . .

[Shadow]

Does a Tension Tester (an example of the type is shown here) come with the bike?  I'm sure it doesn't but thought I'd check . . . .

Nope. Belt tension measurement (zeromanual dot com)

It's not the most reliable thing but a more accurate gauge will be $100's.

Belt tension seems to vary widely with temperature and initial break-in so be sure to have some kind of gauge and prevent having an over-tightened belt.

[Snafuperman]

OK, thanks.

My current bikes are belt driven so I have some experience.  In fact, I can pretty much "feel" the tightness pretty correctly by just pushing on the belt halfway between the sprockets.  I also have an OEM belt gauge to make sure.

[gt13013]

My Zero FXS 2016 ZF6.5 has a drive belt with 14mm width, 8mm pitch, 54.5 cm between the axes of the sprockets.
The bike has made 1613 kms.
I have measured the tension using the Gates 91107 Belt Tension Tester (Krikit tool), and the frequency of the belt vibrations using the Gates' Carbon Drive mobile app.
I have made several measurements for each tension setting, with different positions of the wheel, and I give here the average taken from the most stable results.
From factory, the Krikit tool gives a tension greater than 70 kgs, and the frequency is 102 Hz.
Turning the bolts by 1/4 of a turn, the Krikit tool gives 60 kgs, and the frequency is 79 Hz.
Turning the bolts by 1/2 of a turn, the Krikit tool gives 20 kgs, and the frequency is not measurable.
Turning the bolts by 2/6 of a turn, the Krikit tool gives 25 kgs, and the frequency is 44 Hz.
Next setting: the Krikit tool gives 40 kgs, and the frequency is 72 Hz.
Next setting: the Krikit tool gives 30 to 32 kgs depending on the measurements, and the frequency is 58 Hz.
I have kept this last setting.

[togo]

Ahhh, I'm not so familiar with the english words "groaning" and "screetching", in fact, don't know how to describe that noise which may be "normal" under wet conditions!

The words are onomatopoeic in English.  Screech is high higher, closer to a squeal, while groan is lower.  Monkeys screech but a man with a stomach ache would groan.  But obviously, both are approximations and the sound may differ even when the cause is similar.

[clay.leihy]

Ahhh, I'm not so familiar with the english words "groaning" and "screetching", in fact, don't know how to describe that noise which may be "normal" under wet conditions!

The words are onomatopoeic in English.  Screech is high higher, closer to a squeal, while groan is lower.  Monkeys screech but a man with a stomach ache woudld groan.  But obviously, both are approximations and the sound may differ even when the cause is similar.

Wet belt = wounded wookie

Sent from my Z981 using Tapatalk

[grmarks]

Setting my belt with the Gates Krikit tool to 20 kg (or 30 depending on the wheel rotation position) the belt seems loose. Using the android carbon drive app I get a very consistent 44 /45 (at 30kg) no matter how I strum the belt. When I set the belt to 96 using the app it is very tight, only moves up and down 2 - 3 mm when I push on it with my fingers. Makes me think the 96 - 124 is wrong. It is also more noisy now.
I am wondering if it should be around 60 for the app.
I also think my Gates gage is wrong or I am using it wrong.
The app is a more accurate way to measure.

[togo]

Both are pretty hard to use correctly.

[grmarks]

Both are pretty hard to use correctly.

I found the app really easy to use and very consistent. I just think the values in the manual are wrong.

[hubert]

grmarks, when you set the belt to 96Hz with the app, what's the value shown by the krikit?

[gt13013]

Note that the correspondence between the frequency and the tension involves also the nature of the belt and the distance between the ends of the free part of the belt (same as in a guitar  ).
Since the belts differ among our bikes, and probably the distance also, data from one bike are not necessarily good for another bike.

By the way, I have measured again today for my bike (Zero FXS 2016 ZF6.5 11kW, which has a drive belt with 14mm width, 8mm pitch, 54.5 cm between the axes of the sprockets).
Previous measurement, April 4th 2017, bike had 1613 kms, the Krikit tool gave 30 to 32 kgs depending on the measurements, and the frequency was 58 Hz.
Today measurement, Sept. 1st 2017, bike has 3502 kms, the Krikit tool gives 36 to 38 kgs depending on the measurements, and the frequency 69 or 70 Hz.
Note that I have not changed anything on my bike between the two measurements. So, in that case, the tension has increased with time...

Finally, I noticed that if the belt is vibrated by tapping it with a tool, the frequency is not reliable.
On the other hand, by stretching the belt by hand and releasing it, the frequency is quite reproducible.

[droidish]

I tried to use it and cannot get a proper pluck to happen, so I don't have a reading yet or a good thing to write down on the wiki.

Presumably, one has to find the exact center of free play along the lower belt pass and really twang it with something stiff.

I have used the Gates Carbon Drive app. twice. Once to confirm correct tension as delivered. The second time after I had removed and reinstalled the rear wheel. I find it very user friendly and consistent as long as the environment is fairly quiet. It is much better than the guitar tuners I've used to tension the cam drive belts on my Ducati.

As far as plucking the belt, it doesn't seem that critical to find the exact center. An inch or two off one way or the other seems to get the same reading. My finger gets sore from plucking, so I use the rubber coated handle of a telescoping magnet. Plucking upward, downward, or lightly thumping yield equally good results.