Sachs rear shock

Hello
Still looking into changing spring on rear Sachs shock (GRiSO 1200 8v 2010), have found that Guzzi do a firmer spring for the Norge-part no 981051, i understand it also fits the Stelvio???, does any one know about the spring dimensions etc, if it fits is it stronger than the GRiSO stock spring, also will it fit the GRiSO.
Am also looking at Ohlins 01092 about 800ibs.
All feedback appreciated.
Regards
Stevie

the stock rear stelvio shock spring will fit and work correctly on a GRiSO even though the free length is slightly longer, the stella spring is about 610-625lbs. better than the 485-525 stock GRiSO spring it does match up with the fronts ok and will allow the suspension to balance front to rear. it is a squeeze but it fits,

Thanks for response, any idea on the firmer spring????

about the same as the stelvio

Here is a picture of the stock shock and the Stelvio side by side.  I will probably be putting in the Stelvio shock shortly.  I currently have an Ohlins 800 lb spring on a stock shock.
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I too, am curious about an upgrade. I'm a big dude and the stock shock bottoms out over bigger bumps and potholes. I was considering either buying a Stelvio shock for about $800 (incl. install) or should I just go for the Ohlins 800lb spring (much cheaper)?

buy it used for 75...if you are going to spend 8 bills get a penske the stelvio is for length (to raise the back end) the stock stella shock may or may not fit I did not try that , but I have tried aftermkt stella shocks on the GRiSO and the matris does fit as does a penske. ps the ohlins 1092 is too long to mount easily use a 1091 with spacer, or a 1093 straight

Uzidzit is the resident ghetto suspension pro, no forked tongue there...

Thanks guys!

I think I'm going to drop the cash on the Penske shock. I've already spec'ed it and I just have to save my pennies.

One last question, what sort of upgrade do you suggest for the front? I couldn't find Moto Guzzi on the Progressive site.

Ultimate is Matris complete cartridge kit and springs.
Next downgrade is linear springs & revalve by your local suspension guru, all to suit your weight and riding.

The front Showas are actually pretty good for the most part, but Uzidzit gave a very nice primer on a Penske re-valving if you are interested.

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stacius wrote:

Thanks guys!

I think I'm going to drop the cash on the Penske shock. I've already spec'ed it and I just have to save my pennies.
.

I too like the Penske but the current quote I have is $1500 USD so I want to be sure it does the job..
"UZIDZIT" has mentioned getting a custom build and have the stroke of the shock lengthened by a quarter inch to raise rear end by an inch and give the shock better control over its travel.

Keep us posted

Exhumed this thread from long ago as another lister wanted my impressions of rear shock experimentation re: an 800# spring in the stock shock:

It was an improvement.  I had the stocker's preload wound into the danger zone.  The heavier spring got the ride height correct but didn't make the ride much more compliant.

I sold the '09 and didn't bother changing the shock back to stock.  I have since acquired an '07 and put a Stelvio shock in.

It raised the rear of the bike so the front works a bit harder, adds shock travel and the springing seems dead on.  That's good because there is no preload adjustment.

If I sell this bike and get another GRiSO (cough)the red one(cough).  That Stelvio shock will be the first thing I change.

I am a big monkey at 6'4" 220Lbs, 35" inseam so YMMV

You can sort of see the different ride height in this picture:
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DW

Dig the training wheels, DW.

Street wrote:

Dig the training wheels, DW.

Stability is important to me...

I'm considering this Ohlins, which has adjustable length and is only $831 when purchased direct from Italy (no VAT when delivered to U.S.)

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Comes with a spring to support a jockey (50-60 kg). What do you weigh?

Adjustable length is great, set it up with mounts 330mm eye-to-eye before installation.
Once you have the correct spring rate, and correct sag settings, this not only increases rear ride height, but also reduces rake and trail for lighter faster steering.
But the biggest advantage to me is the rocker arm in the suspension linkage moves a little further around in its arc. This actually increases the ratio a little giving a more compliant action and a real rising rate as the suspension compresses.

ghezzi wrote:

Comes with a spring to support a jockey (50-60 kg). What do you weigh?

Adjustable length is great, set it up with mounts 330mm eye-to-eye before installation.
Once you have the correct spring rate, and correct sag settings, this not only increases rear ride height, but also reduces rake and trail for lighter faster steering.
But the biggest advantage to me is the rocker arm in the suspension linkage moves a little further around in its arc. This actually increases the ratio a little giving a more compliant action and a real rising rate as the suspension compresses.

I weigh 180 (lbs.)  dry, so will choose a heavier spring.  I need to call them first to confirm whether my weight should be with or without gear.

Thanks for the advice - I'm a novice at this, but didn't quite follow what you're saying about the linkage.  Is this due to the length you specified?  I gather 330mm is a bit longer than stock?

Yes, my Bellagio has all the same part # for the swingarm and suspension linkages.
My stock shock was about 310 mm, when I fitted the GRiSO shock (about 320 mm) my suspension guru asked me to plot the movement ratio between shock and axle.

Topped out Bellagio shock - 1 mm shock compression would equal about 2.6 mm axle travel.
Bottomed out - 1 mm shock compression would equal about 2.1 mm axle travel.
This is what is called rising rate, it gets stiffer the more it compresses = compliant ride (supposedly)

Eventually I fitted a modified Matris R shock that is now 330 mm eye to eye. So my initial ratio of 2.6:1 is now higher. I haven't measured it but I suspect my ratio starts close to 3.0:1 and finishes closer to 2.3:1, I also have longer travel than stock. My initial travel was softer so I installed a heavier spring just to see. Firm but compliant with an 11.0kg spring, I may go back to the 10.5.
I'm 100kg wet. Bella is 202kg wet.

Thanks, Ghezzi.  I was thinking I wanted a longer shock than stock as the rear feels low when I'm accelerating out of corners.  Could be due to the wimpy stock spring of course. I also want to go to 1" dropped pegs, so wanted to raise the bike a bit.  Your experience gives me more confidence in the plan.  I can play with it since the length is adjustable.