Wildgoose Chase Moto Guzzi

General Category => General Discussion => Topic started by: Kitze on May 06, 2020, 04:27:48 PM

Title: Stock fork springs V85tt
Post by: Kitze on May 06, 2020, 04:27:48 PM
So Iíve search the internet. Iíve searched here. Gone blurry eyed reading the Threadfest. Iíve talked to several dealers. And Iíve emailed my contact at Piaggio USA.
Apparently info on the fork springs is either a deep dark trade secret. Or lost to history.
Does anyone have any info on the specs? Bueller??
Title: Re: Stock fork springs V85tt
Post by: Vagrant on May 06, 2020, 04:36:26 PM
well what do u really need to know. the V85 is as good as it gets without spending $3K xtra. 95% of buyers will be happy. 
Title: Re: Stock fork springs V85tt
Post by: Kitze on May 06, 2020, 04:55:10 PM
At a minimum Iíd like the rate. Ideally rate, free length, coil count, Symmetry  etc.
For my scrawny ass (145#) the forks are way too stiff.
Title: Re: Stock fork springs V85tt
Post by: Trialsman on May 06, 2020, 06:07:09 PM
I am not much heavier and they were too stiff for me as well.  It was more the compression damping, so I halved the viscosity of the oil.  15wt > 7.5 wt. same volume.   It seems just right now.  You might give it a try.
Title: Re: Stock fork springs V85tt
Post by: slopokes on May 06, 2020, 06:49:48 PM
If you put on fifty pounds the front end will be fine😃
Title: Re: Stock fork springs V85tt
Post by: Kitze on May 06, 2020, 06:57:16 PM
I am not much heavier and they were too stiff for me as well.  It was more the compression damping, so I halved the viscosity of the oil.  15wt > 7.5 wt. same volume.   It seems just right now.  You might give it a try.
I definitely need to tweak the dampening. But as Iím getting less than 1/2 of the sag I should the springs need to go down in rate.
Iím curious where you got the oil viscosity. Both the service and owners manual call out 7.5 wt. Did I miss an update?
Title: Re: Stock fork springs V85tt
Post by: Trialsman on May 06, 2020, 09:12:37 PM
I definitely need to tweak the dampening. But as Iím getting less than 1/2 of the sag I should the springs need to go down in rate.
Iím curious where you got the oil viscosity. Both the service and owners manual call out 7.5 wt. Did I miss an update?

You are correct.  I was going from memory which was not accurate about the starting wt.  In halving the wt I would have mixed 2.5wt and 5wt to come up with something around 3.75wt.  It took the harshness out of square edged bumps.  Sorry for the mix up.
Title: Re: Stock fork springs V85tt
Post by: mechanicsavant on May 07, 2020, 07:05:23 AM
Ya might wanna reduce preload on front springs if possible (shorter spring spacers) to get sag correct , schedule 40 abs works w/washers vs. cutting OEM spacers .
Title: Re: Stock fork springs V85tt
Post by: Kitze on May 07, 2020, 10:19:53 AM
Ya might wanna reduce preload on front springs if possible (shorter spring spacers) to get sag correct , schedule 40 abs works w/washers vs. cutting OEM spacers .
preload is all out. Shorter spacers will move the measurements and can help. But ultimately sag is based on spring rate. I donít mind changing springs. I actually have a fair number of springs from various race and track bikes. What I donít have is a spring dynamometer to get a baseline on the OEM springs. On bikes with handed adjustments, such as the V85, its very common to have asymmetric spring rates and often time length.
In normal times springs are 4-5 days out. Now??? Seems like everything is 2-3 weeks. Iím guessing, based on feel, that the installed springs are .95. But Iíd like to avoid guessing and having to do multiple swaps.
I guess Iíll have to either build a dynamometer or wing it. I know several companies sell kits. But they all use progressive rate springs, which I hate. And their rates are calculated using weight only. Which ignores several key factors. Geometry, sprung/unsprung weight, stiction etc.
Oh well.
Title: Re: Stock fork springs V85tt
Post by: Goose85TT on May 02, 2021, 12:14:31 PM
Kitze, I too hate progressive fork springs for all the reasons explained on the RaceTech website. I found a review of the V85TT by Ultimate Motorcycling.
In the article he says the V85TT forks are KYB brand sourced from the Aprilia Dorsoduro 900. Have you learned anything new since your last post?
Title: Re: Stock fork springs V85tt
Post by: Goose85TT on June 21, 2021, 07:37:30 AM
The fork springs in the V85TT are progressive. see the fork internals from my 2020 V85TT
(https://i.ibb.co/093cHTy/IMG-4497.jpg) (https://ibb.co/093cHTy)

(https://i.ibb.co/tcFWNFJ/IMG-4498.jpg) (https://ibb.co/tcFWNFJ)

(https://i.ibb.co/mF5FxsS/IMG-4496.jpg) (https://ibb.co/mF5FxsS)
Title: Re: Stock fork springs V85tt
Post by: Goose85TT on June 21, 2021, 07:52:56 AM
The V85TT fork springs are not only progressive but very stiff. If you weigh more than 200lbs you may not have noticed but if you weigh 150 as I do the forks are torture. With the preload backed all the way out my forks static sag was about 1 inch but when I climbed on there was no additional sag. So I got with AF1 racing in Austin TX and they fixed me up with custom Andreani fork cartridges with linear springs for my weight for $600. Amazing! its a whole different bike. I owned a KTM 1190 Adventure R a few years back and thought suspension could get no better than that but what a difference these cartridges made. The right cartridge was no problem to install, but the left one you need special tools. I took the left one to a local shop, Fast Italian Bikes in Murfreesboro TN and Mike did the work. I attached a picture of the instructions.
(https://i.ibb.co/FBJbKkd/IMG-4482.jpg) (https://ibb.co/FBJbKkd)

(https://i.ibb.co/VgTdWfc/IMG-4483.jpg) (https://ibb.co/VgTdWfc)

(https://i.ibb.co/qBm5Cs9/IMG-4484.jpg) (https://ibb.co/qBm5Cs9)

(https://i.ibb.co/pdws0sT/IMG-4485.jpg) (https://ibb.co/pdws0sT)
Title: Re: Stock fork springs V85tt
Post by: Goose85TT on June 21, 2021, 07:56:59 AM
Andreani Cartridges pictured
(https://i.ibb.co/Yy0xKc1/IMG-4488.jpg) (https://ibb.co/Yy0xKc1)

(https://i.ibb.co/KhntG7C/IMG-4489.jpg) (https://ibb.co/KhntG7C)

(https://i.ibb.co/yd7NpM6/IMG-4494.jpg) (https://ibb.co/yd7NpM6)

(https://i.ibb.co/D7FYtv4/IMG-4495.jpg) (https://ibb.co/D7FYtv4)