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Rear shock works fine BUT....


Guest Nogbad

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Guest Nogbad

OK, the damping adjustment front and rear seems to work and make a difference. After reducing the compression at the rear to 10 clicks in, the bike is more comfortable and handles a lot better on ripply bends with rough surfaces.

 

However, it now bottoms on bigger bumps OUCH. Increasing the preload causes it to top out on crests and makes the sag too small.

 

Either A. The rear suspension is simply too crude having no rising rate linkage.

Or B. The stock springs are too soft / wrong rate or something.

 

I am not a heavy guy at about 150 lbs

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OK, the damping adjustment front and rear seems to work and make a difference. After reducing the compression at the rear to 10 clicks in, the bike is more comfortable and handles a lot better on ripply bends with rough surfaces.

 

However, it now bottoms on bigger bumps OUCH. Increasing the preload causes it to top out on crests and makes the sag too small.

 

Either A. The rear suspension is simply too crude having no rising rate linkage.

Or B. The stock springs are too soft / wrong rate or something.

 

I am not a heavy guy at about 150 lbs

58459[/snapback]

 

Given that there's no rising rate linkage, the V11 would seem to be an ideal candidate for a progressive rear spring or air shock. Does Fournales make a shock for the monoshock Guzzis? Or Prog. Suspension offer a replacement spring? I know that several have written about sub'ing FZ1 springs for the stock fork springs; what manufacturer's stock shock parallels the dimensions of the Guzzi stocker, so that prog. springs for that alternate might be obtainable?

 

Tis a puzzlement... :huh:

 

Great question for you to have asked, tho'!

 

:mg:

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Guest Nogbad

I have e-mailed this place. I've really been enjoying my V11 lately, and am moving away from the idea of swapping it for a Buell.

 

So I think I'm going to have the bike professionally set up to suit me, if necessary with new progressive rate springs front and rear. We'll see what these guys recommend!

 

Set-Up Engineering

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So I think I'm going to have the bike professionally set up to suit me, if necessary with new progressive rate springs front and rear. We'll see what these guys recommend!

 

Set-Up Engineering

58496[/snapback]

 

Since you seem to have the correct spring rate, it sounds like the high-speed compression damping is too high.

 

It will be interesting to hear what Setup recommends. I think that the answer is to have a shock with position sensitive damping (which I believe is what the WP shocks on the link-less KTMs have). A close second is to have both low and high speed compression damping adjustment.

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Since you seem to have the correct spring rate, it sounds like the high-speed compression damping is too high.

 

It will be interesting to hear what Setup recommends.  I think that the answer is to have a shock with position sensitive damping (which I believe is what the WP shocks on the link-less KTMs have).  A close second is to have both low and high speed compression damping adjustment.

58511[/snapback]

I live about 2 miles from Set Up, friendly and knowledgable bunch. I popped in there on the V11 once and they gave me some free advice, as I had backed the pre-load off the rear shock to it's minimum to try and help get the over-stiff rear-end to respond better on bumps. I was aso concerned that, in moving the rear reservoir union I might have lost the pressurisation, which I hadn't btw.

It was soon clear from what they said that I'd over-done it, but they liked the front end settings (all this based on a quick "bounce each end of the bike up and down a couple of times-you don't get much of anything for free!). The front end was pretty close to standard settings.

I also got to dribble over Ewan Magregor's immaculate MV Agusta :wub:

 

Every test I've read in American bike mags of the Scura have criticised the behaviour of the rear suspension over bumps, and as they say, ANY suspension can be made to work well on smooth roads! My view is it comes down to 3 things;

1/ The rear suspension has to be overly-stiff (in relative terms) to take account of un-sprung weight from the bevel box.

2/ The linkless set up means the set has to be over-stiff to prevent "bottoming out" (i.e.reaching limit of travel)

3/ The rear swing arm is too short (one scura test compared the length with a Honda VTR1000, which was a good 5 inches longer from memory), hence limited travel.

 

I think given loading a Scura up with top notch components doesn't really improve things greatly, you're gonna struggle to get a step change in behaviour?

Just my 2 cents...

 

Dave

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HyperPro makes a rising rate spring for our Sachs, however I am concerned the spring rate is too heavy for the under 100KG riders.

The European HyperPro may have more options than HyperProUSA.

If you dare read through http://www.v11lemans.com/forums/index.php?...opic=4213&st=75

you can see what we know about their springs.

Here is the Readers Digest® version for the rear spring:

They give it a low measurement of spring rate

= 90.13 Nt/mm. = 9.190556 Kg/mm = 515.0929 lbs/inch

and a high measurement of rate

= 144.2 Nt/mm. = 14.70407 Kg/mm = 824.103 lbs/inch

The low measurement is probably suitable for a 90KG rider, while the high measurement is probably suitable for a 150KG rider.

The low measurement may or may not get sucked up by the preload and the high measurement, may or may not be even within the range of travel.

So, we need a guinea pig.

I put a 475#/inch spring on mine and suspect it is a little too light for my 210++ pounds.

I had to set the preload on tight side to keep it from bottoming too easily.

I think a progressive spring would be better, but I am thinking 450# after preload transitioning to 600# at the bottoming point. so the HyperPro numbers scare me, but they may not be bad, depending on how they measure the spring.

The bike is alot more comfortable on the rear hits if I slide forward, so what I really like is the idea of a longer swingarm....or a seat that is comfortable when seated right up at the tank.

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  • 1 year later...

So, what's the O.D. of the stock Sach shock [ergo, what I.D. should be used when ordering springs?]

 

I've seen posts stating 2.25" ID springs & 2.50" ID springs; I suspect the latter is correct, 'cause by eyeball it looks like the 2.25" springs would be likely to rub. But I'd like to be certain...

:mg:

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Guest ratchethack

Skeeve, the OD of the Sachs shock isn't significant. The spring retaining collars that actually accept the springs are 2.2".

 

The stock Sachs spring measures 2.232" ID, and 3.090" OD. That's not accounting for paint. ;)

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This thread has some info:

http://www.v11lemans.com/forums/index.php?...=5488&st=15

Fuelcooler and I each went with 2.25" x 6"

He got a 500# Eibach, and I got a 475# Hyperco Hypercoil for my Sachs, which was too light for my ~230 riding weight unless my seating position was all the way forward.

I now have a 550# Hypercoil on my Penske, but I am seriously considering the HyperPro (different company than HyperCo) for their rising rate spring.

I previously thought it would be too stiff, but I think it is worth a gamble to try it.

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Timely post. I am now set up to offer all HyperPro products.

 

I can offer a spring kit (front and rear) for the V11 Sport folks (discounted if you mention this thread); http://www.guzzitech.com/store/HyperPro-FS.html

 

Watch for all the rest of the products (mono rear shocks & steering dampers) linked on the main page at GuzziTech.com in the very near future.

 

HPMono-640Emul-sm.jpgHPMono-461sm.jpg

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:doh: I just received my HyperPro damper. I'm sure it would have been less hassle from you...

 

VERY happy with it! Was running the POS Bitubo on zero setting until I discovered it had shit the bed and was screwing up my steering. Ran without a damper at all for a while and thought that was pretty good until I put the HyperPro on. Everything is noticeably much smoother now. Happy I coughed up the dough.

 

A rear spring is in order now though... :)

 

cheers,

 

Rj

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BMG,

 

Do you have a link and part number for the damper?

 

( My 1.0 springs from Traxxion are here , with their excellent instruction pac and spacers; the Ohlins should be at Corse Motorsports tomorrow. )

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