Matris+Slacker=Suspension Hacker

I got the bike back yesterday with the Matris fork cartridge kit up front and the R shock in the rear. Even without any adjustments the 140 mile (225km) ride home was fairly amazing. I think that the front forks bottomed out only about five times on some particularly bad joints and transitions at 75MPH (120km/h) speeds with, as it turns out, no preload at all on the front end. This is a far cry from the original setup where the front end would bottom out on nearly any imperfection in the pavement.

After getting home I got to play with the new workshop tool, a Motool Slacker. It is an awesome bit of kit for doing suspension measurements. They have a new iPhone app that allows you to set the zero value, see the readings for static and rider sag, and record those readings with a tap of the phone screen. This makes it largely a one person operation to adjust the preload.

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I managed to get the solo sag settings dialed in yesterday afternoon and got my gal on the back of it this afternoon to play with the two-up “pillion” settings. I need to go back at the two-up settings one more time as I’m sure that adding the ten clicks (5mm) of rear spring preload must have changed the front fork sag a bit. Thus far the front fork is at the Matris-recommended 10 clicks each on the compression and rebound, with 20 clicks (10mm) of preload. I’m guessing that I’ll have to add a click or two of compression on the two-up settings to minimize any diving of the front end with the increased inertial load on the bike, and maybe a bit more preload on the rear spring. This is new territory for me and I have found the Ohlins suspension setup manual to be quite helpful, along with the Dave Moss Tuning YouTube videos.

I haven’t yet checked the rear shock low and high speed compression settings, or the rear shock damping. I did have to back off the 2mm of factory-set preload to get to 26mm of sag on the rear end, but the fuel tank was nearly empty and I wasn’t wearing all my gear in the 90+F (32C) heat. The mechanic did rotate the position of the hydraulic preload unit so that I can get a ball end Allen bit in to it by going between the Mistral riser pipe and the tire. Checking and setting the high and low speed compression settings looks like it will be a bit more challenging, but it’s easy to drop the exhaust to get to them.

My gal and I are planning on a ride up to Mt. Lemmon in Tucson, Arizona on Tuesday. After a bit more solo riding I’ll check things again to see if the springs have settled a bit before resetting the sag. Any advice on settings would be welcome.

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I have the v1 version. Going to give it a shot!

awesome info! The tool runs at $159 on amazon... I have a Matris SD in the back and stock in the front that I still need to dial.
Giuseppe

My gal and I got out yesterday for a ride up to Mt. Lemmon, just outside of Tucson, Arizona, to try out the new Matris suspension. I upped the rear preload to 12 clicks (6mm), increased the compression in the front forks by two clicks (to 8 clicks) and backed off on the fork rebound by two clicks (to 12 clicks). The handling and the ride were both amazing, especially at the rear where it was nearly “magic carpet” smooth. I don’t think that we bottomed out at all during the trip, front or rear, even on very rough pavement. The front still needs slight tweaking but it is pretty darned close.

The rear shock is set up at 2mm longer than stock. That, combined with proper spring rate and sag settings has transformed the bike into a flickable and level-riding dream. I noticed that my stance on the bike is more secure and that my hands and wrists are much more comfortable too. I need to go back with the Slacker and verify the new sag settings just for the sake of recordkeeping. I’m going to also try backing off on the fork rebound another couple of clicks for the two-up settings and see if I can get just a bit more smoothness up front. Overall, the Matris suspension is an outstanding upgrade to the bike.

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Tom,

I'm intrigued by your progress & result with the suspension; you obviously value & are willing to pay for quality suspension parts & then have someone instal them. So I'm concluding that the Slacker suspension tool has some merit as well. Can you tell us more about your experience?

Cheers Tim

Nobleswood wrote:

Tom,

I'm intrigued by your progress & result with the suspension; you obviously value & are willing to pay for quality suspension parts & then have someone instal them. So I'm concluding that the Slacker suspension tool has some merit as well. Can you tell us more about your experience?

Cheers Tim

Tim,

While I wasn't wanting or expecting to gain expertise on motorcycle suspensions, the GRiSO pretty much forced me into it. My speculation is that a major reason that we see so many one owner low mileage Grisos up for sale soon after they're purchased is that the lackluster suspension makes them unpleasant to ride. In shopping for a "retirement" bike I first thought that I'd like the Guzzi V7 Special Anniversary model. They weren't in yet but when Zee and I sat on a V7 III it was immediately obvious that the thing would need heavier shock springs on the rear, and by inference also on the front. Even with that the rear shocks would be emulsion-type units. Adequate perhaps, but certainly not great. I also looked at a couple of different super scooters, and had the GRiSO that I bought not popped up just when I was looking to buy we would probably be tooling around on a Kymco.

One thing that I've learned over the past four months is that nearly all bikes, regardless of make, unless they are high end models, are greatly improved with properly selected and set up aftermarket or rebuilt suspension parts. With my other Guzzis I never thought much about it: There are what they are, and I had no expectations. But then again the flatlands and arrow-straight back roads of Michigan aren't in the same league with the curvy, hilly, and rough back roads of Arizona. It wasn't until I started poking around here on The Ghetto (at the recommendation of my bike's previous owner) that I became aware that you could have a bike that was both comfortable to ride and would handle properly.

As for the suspension measurements I did the initial ones the old-fashioned way, with a metric folding ruler, by myself...pain in the butt. Even with the heavier Race Tech spring that a previous owner had put on, the bike had 74mm of rider sag at the rear...solo! I cranked (beat actually) the adjuster down by 5mm and got the sag down to a still abominable 62mm in the rear with 37mm up front. The ride was wretched and beat us up badly, both solo and two-up. It was time for a solution if I was going to keep the bike.

You can see in my notes that I did consider other options in looking for used parts and stiffer springs on Ebay, but the problem was that there was no certainty as to the outcome. Consequently, I decided to just spend the money and get a suspension that would work. Things were complicated by the fact that I'm frequently switching between solo and two-up riding and that I don't have a garage (or my tools) here at the little winter condo in Arizona. The quest to find the proper parts took some doing. I contacted the local (or is that alleged?) Guzzi-Aprilia-Ducati-Vespa-Kymco-etc dealer only to be told, relative to a GRiSO suspension upgrade, that "we're an Ohlins dealer" and that my GRiSO wasn't in their Ohlins book. Their suspension sales rep said he'd get back with me but never did. Had I known about AF1 at the time they probably would have been the next stop but I went with GT Motors as they seemed to have all the part numbers figured out and upon further inquiry seemed to know what would work for my needs. They could have rebuilt and reconfigured the original Showa forks for about $550, but I would have had to either ship the forks to them or take the bike to them. However, the lack of having a garage where the bike could sit forkless for a couple weeks was an issue.

The parts were ordered and five weeks later they were in. In the interim I needed to find a mechanic/dealership to put them on and to take care of some other maintenance items (head, swing arm, and pivot bearings) while they were at it. Again, no response from the local alleged dealer when I filled out their online service request form. I guess they didn't want my $800-1000 for some basic mechanic work. GT Motors is a 10-12 hour ride away...too far. Cliff up at Manic Moto (a Guzzi/Beta dealer) in Queen Creek, Arizona agreed to do the work, but there was a three week wait to get in. I waited the three weeks and rode the two and a half hours to get it to him. He recommended that on my ten-year-old bike that while we had the forks off that we simply do the full service, seals, bushings and all. I agreed as I wanted to have a baseline for future maintenance.

While Cliff had the bike (some parts had to be ordered) I was watching some of the Dave Moss Tuning videos on YouTube. As it turns out lousy suspension components and setups are fairly common across most brands of bikes. At last we Guzzisti don't have to contend with throw-away shocks like some of the Japanese crotch rockets come with. Dave Moss had a video showing how easy it was to do the sag measurements on a bike using the Motool Slacker. In the interest of maintaining my relationship with my significant other I sprung for the Slacker since it provided a straightforward one-person means by which to take the sag measurements. Like most specialized shop tools, you need them when you need them, and the other 99.95% of the time they just sit there. I figured that some of my other Guzzi friends would be able to use it as well as they too are contending with suspension problems. With what I learned from the DMT videos and the Ohlins suspension setup manual it was fairly easy to get the sag settings within range. I am currently reading Race Tech's Motorcycle Suspension Bible to have a better understanding of how compression and rebound settings work.

The new iPhone Motool Service Assistant app for the Slacker V4 is a great help as it allows remote reset and recording of the data from the Slacker. It also allows you to keep notes on settings and changes. They are also very good about coming up with sag setting recommendations for bikes that are not already in the app. We went to do the measurements on a friend's 2002 California EV which wasn't in the app. A quick request via the app had the bike added the same day.

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We got back to Michigan on Saturday and I spent most of the day yesterday adjusting the valves, changing the fluids, and washing my 2001 California Special 1100. Zee and I went for a ride today across town to visit some Guzzi friends and all I could think after comparing it to my Matris-equipped GRiSO is, “This thing’s a wallowing pig!” A quick check this evening with the Slacker tells the tale.

Here we go again...I’m thinking Shock Factory adjustable shocks on the back and a Matris F15 kit for the front forks. The bike has 29,000 miles on the clock, is in good condition, and has long been paid for, so it’s probably worth sinking a few dollars into. Does anybody have any recommendations?

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