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Discussion Starter #1
Here's a question - how do you find out your rear suspension travel?

It's no good looking in the handbook, because most of us have changed our rear shock absorbers and different brands have different lengths of travel. Either follow a rule of thumb when setting the loaded sag - 10 -12 mm or 25 -30 mm depending on which experts article you read, or use the usual advice of one-third travel for loaded sag. This brings me back to my first sentence!

If you measure the stroke of the rear shock, say 9 CM, then the rear loaded sag should be 6 CM, except that the wheel travel on a SC is more than the stroke of the shocks, because those shocks are angled forward and the wheel spindle is way back from the lower shock mount, which gives greater travel at the wheel.

What's the answer? The only way that I can see is to measure the shocks themselves, so that (as above) the stroke of the shock is 9 CM, therefore, the loaded stroke should be 6 CM.
 

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You may be over thinking it. Just use the sag measurement that you desire, then go from there. All else will fall into place..I think...
 

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Here's a question - how do you find out your rear suspension travel?

It's no good looking in the handbook, because most of us have changed our rear shock absorbers and different brands have different lengths of travel. Either follow a rule of thumb when setting the loaded sag - 10 -12 mm or 25 -30 mm depending on which experts article you read, or use the usual advice of one-third travel for loaded sag. This brings me back to my first sentence!

If you measure the stroke of the rear shock, say 9 CM, then the rear loaded sag should be 6 CM, except that the wheel travel on a SC is more than the stroke of the shocks, because those shocks are angled forward and the wheel spindle is way back from the lower shock mount, which gives greater travel at the wheel.

What's the answer? The only way that I can see is to measure the shocks themselves, so that (as above) the stroke of the shock is 9 CM, therefore, the loaded stroke should be 6 CM.
For starters it needs correct springs for your weight.

I have the YSS shocks with progressive springs . They have an O ring on the shock shaft which helps setting sag. A small tie wrap works too.

You can run a bit more sag with progressive springs since they get stiffer as they compress. I roughly set the preload so the O ring on the shock shaft doesnt get pushed all the way down to the bump stop under normal riding conditions, say around 10mm to spare. Then tweak it for front to rear geometry etc....
 

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I have the YSS shocks with progressive springs .
How do you like the YSS shocks?

I'm considering a shock upgrade. I might be one of the few with the original rear shocks.

I'd sure like something more compliant.
 

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Discussion Starter #5
Most riders here have YSS and they are pretty good, certainly way better than the standard back breakers. They are well made too and mine look brand-new still after about 6-7 years.
 

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Thanks for the feedback.

Which model YSS and where's a good place to look for them?

OK, a little googling turned up the SC suspension summary thread. I'll start there.
 

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How do you like the YSS shocks?

I'm considering a shock upgrade. I might be one of the few with the original rear shocks.

I'd sure like something more compliant.
Quality is ok, and price was competitive as I bought direct from the Thai factory across the border....
Mine are the YSS piggyback with 30 click comp, 60 click rebound, preload adjustment, and 10mm height adjustment.
That's a fair range of adjustments so with correct springs for your weight, you should be able to dial in more (or less) compliance than would be available with the stock shocks.
 

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Discussion Starter #9
Yes, but angled shocks are softer, so the rear wheel will move more. We still need to know the wheel travel with a given pair of shocks.
 

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YSS Shocks

I just got a set of YSS Z366-310-TRL shocks for my bevel Duc and I only have a few miles on them, but they seem very good, well made and they were rationally priced unlike the "gold shocks", which I'm sure are wonderful but probably not three times as wonderful for a street bike. Bought them from Klaus Huenecke at empperf.com sprung for my weight and with discounted pricing. It was an excellent buying experience. Highly recommended.
 

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The only way that I can see is to measure the shocks themselves, so that (as above) the stroke of the shock is 9 CM, therefore, the loaded stroke should be 6 CM.
The YSS shock travel is stated as 90mm, but the available travel is closer to 72mm due to the bump stop.

The ducati website lists the rear wheel travel
for the GT its 133mm / 5.2 "
the Sport is 130mm / 5.1

However, I'm guessing those are theoretical values and dont account for the shock shaft travel lost from the bump stop.
When I do my sag measurements, a 27mm move in the shock shaft correlates to 39mm at the rear axle measured vertically. Thats a ratio of roughly 1:1.45
With around 72mm actual shock shaft travel available (90mm minus the bump stop) the available rear wheel travel would be ~105mm (72mm x 1.45) .

If you have a center stand, or similar way to support the bike, you could measure the rear wheel travel by having the shocks (or a shock) fitted without the springs. Makes it easier to lift the rear wheel through its full range of travel for measurement.
 

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I run my YSS shocks for years now & have to say that they work perfect.

I have YSS RG 362-380 TRCL- 08 AB with 20 click for compression and longer than standard 20-30 nm springs. The shaft length of the original shocks and YSS is more or less the same.

Even under harsh riding in the twisty roads of Tuscany i have a good balance between front and rear... that's what counts.

Front & rear tire are used evenly... the set up works very good in combination with the Andreani cartridge front fork.





 

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If you were in the USofA I would suggest you talk to Rick at Cogent Dynamics. He rebuilt my stock '06 Sport Classic shock to work specifically for me. He said that the basic shock was a great starting point for his revalve and respring!
He has built all of my shocks for me.
 
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