Shock dilema!

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D-Rider · #31 Post by **D-Rider** » Tue Dec 20, 2011 8:21 pm

That chart has me confused - are you sure it's right?

From the part numbers they seem to refer to Ohlins aftermarket shocks for the Aprilias .... however the 4th row down suggests the pre '04 Mille-R has a shorter shock than either the 99-01 Mille or 02-03 Mille, a slightly different stroke to the 02-03 Mille and a very different stroke to the 99-01 Mille.

My understanding is that the (OEM) Mille-R Ohlins uses the same linkages as the Sachs shocks from Milles of the same years and is (approximately) of the same length and stroke of the appropriate sachs shocks.

I know that few will want to replace the OEM sachs shock on their Mille-R with an aftermarket one but that info just doesn't seem to add up.

#32 Post by **mangocrazy** » Tue Dec 20, 2011 8:50 pm

Hi Andy,

I'm not able to say whether the info Flatlander provided is kosher - I just reformatted it and made it more legible.

I have my suspicions that what you see there are the aftermarket Ohlins options for the various V60 models, not what was fitted as OE. The reason I say that is that the 46PRCLS code breaks down as:

46 = shock piston size
P = Piggyback damper
R = Rebound adjuster
C = Compression adjuster
L = Length adjustable end-eye/clevis (i.e. ride height adjuster)
S = Hydraulic spring-preload adjuster with hose

Now only the aftermarket items ever had the Hydraulic preload adjuster, of that I am sure. Also, bear in mind that this is Ohlins' view of Aprilia model years, and I don't believe those to be reliable.

Also, there definitely was a difference in stroke between the earlier RSV aftermarket shocks and the later ones. The earlier shocks would have been set up for the Falco-style linkages, and these have a higher linkage ratio than the later linkages. As a result the later shocks would need more travel, to cope with the lower ratio linkages.

The 2004> Mille entry refers to the Post 2004 Milles, not the Pre 2004 Milles; i.e. the Milles with the more angular swing arm.

#33 Post by **mangocrazy** » Tue Dec 20, 2011 9:02 pm

However one thing does strike me as interesting is that Ohlins specified a softer spring rate for the aftermarket Falco than they did for the early RSV Milles, even though they were using the same linkages. OK, it wasn't softened up by much, but the spring rate was softer:

RSV Mille early spring code is 1093-54 - this works out at 140 Nm / 14.27 kg/mm / 799 lbs/in spring rate (and 150 mm length)
Falco spring code is 1095-49 - this works out at 130 NM / 13.25 kg/mm / 742 lb/in (and 180mm - a substantially longer spring)

D-Rider · #34 Post by **D-Rider** » Tue Dec 20, 2011 9:19 pm

mangocrazy wrote:
The 2004> Mille entry refers to the Post 2004 Milles, not the Pre 2004 Milles; i.e. the Milles with the more angular swing arm.

However that actually says PRE 04 Milles - the inequality would need to be the other way round to indicate Post 04

#35 Post by **mangocrazy** » Tue Dec 20, 2011 9:23 pm

Really?

I always thought that < = less than, > = more than...?

As in:

http://beta.morethan.com/?rw.cm=Google, ... fAod2F51lQ

D-Rider · #36 Post by **D-Rider** » Tue Dec 20, 2011 9:49 pm

X < Y means X is less than Y (or Y is greater than X)
X > Y means X is greater than Y (or X is greater than Y)

The thing on the broad side of the inequality is the larger, the thing on the side of the point is the smaller whichever way round the inequality symbol is drawn

#37 Post by **mangocrazy** » Tue Dec 20, 2011 10:07 pm

OK, well I've re-worked it, made the entries in chronological order and removed the '>' symbol...

D-Rider · #38 Post by **D-Rider** » Tue Dec 20, 2011 10:37 pm

Thanks Graham - that makes a lot more sense.

It also shows that the shock of the later bikes is likely to work - though it might need lengthening (though that's not certain). I guess the height adjuster may bring it into range as long as you don't want the maximum ride height that you can achieve with the earlier shock.

#39 Post by **mangocrazy** » Tue Dec 20, 2011 11:08 pm

D-Rider wrote:It also shows that the shock of the later bikes is likely to work - though it might need lengthening (though that's not certain). I guess the height adjuster may bring it into range as long as you don't want the maximum ride height that you can achieve with the earlier shock.

I'm not so sure... Standard length on the 2004 onwards RSV shock is only 313 mm. From that you have adjustment available of +3.5mm (i.e. 316.5 mm) or -2.5mm (i.e. 310.5 mm).

When you consider that a standard (unadjustable) Ohlins Falco has 319mm length, and the 02-03 Mille has 327mm at full extension, the '04 shock looks pretty substandard. I certainly wouldn't want one. The steering will be markedly slower than a bike fitted with the standard blue spring and would probably suffer side-stand issues (too upright on the stand).

The only way it could be recommended is if a 'person of reduced stature' (i.e a short-arse) was looking for a way to reduce seat height.

I suspect this last observation may generate more heat than light...

flatlander · #40 Post by **flatlander** » Tue Dec 20, 2011 11:11 pm

Os sorry it was late bit yes it appears kosher AFAIK and from what I read up on they did change the geometry from the earliest bikes which was reflected in the pivot point and the triangles. As an aside where is the bloody AP number

#41 Post by **mangocrazy** » Tue Dec 20, 2011 11:16 pm

I think they only have the AP number stamped on them if they're an aftermarket part. If they were originally fitted to an RSV or Tuono from the factory (as most of them were) I don't believe you'll find one. Aftermarket Ohlins shocks make up a small minority of the total available.

It's only the aftermarket ones that have the hydraulic preload adjuster (he says smugly...)

flatlander · #42 Post by **flatlander** » Tue Dec 20, 2011 11:25 pm

Thank goodness for that

I did notice on one of my trawls that the fut armchair had a similar base number to the one I have but the top number is different

D-Rider · #43 Post by **D-Rider** » Tue Dec 20, 2011 11:38 pm

mangocrazy wrote:[
I'm not so sure... Standard length on the 2004 onwards RSV shock is only 313 mm. From that you have adjustment available of +3.5mm (i.e. 316.5 mm) or -2.5mm (i.e. 310.5 mm).

Doh yes - I wasn't thinking .... I was reading that as a tolerance rather than an adjustment range .... without thinking what crap control of dimensions that would imply.

... so back to my suggestion that it would need to be extended - which would probably be quite easy by making a longer bottom mounting.

MartDude · #44 Post by **MartDude** » Wed Dec 21, 2011 2:06 am

flatlander wrote:Thank goodness for that
I did notice on one of my trawls that the fut armchair had a similar base number to the one I have but the top number is different

Kindly leave my base alone.

Aladinsaneuk · #45 Post by **Aladinsaneuk** » Wed Dec 21, 2011 9:09 am

and credit to Blinkey - he did offer me the shock back.... but that might have been because he then might have been able to give a home to a remote preload ohlins that is, HOPEFULLY currently in ther post - I am intending to get out for a ride on boxing day to go scare the natives....