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Nasty Fork Oil...

Touringman

Cruisin' Guzzisti
Joined
May 2, 2014
Messages
162
Location
Red Oak TX
Finally got around to installing the Matris spring and spacer kit on the 1400 Touring this weekend while doing the 10,000 mile service. (yes I know. I do the services at 5000 miles, 'cause i'm old and its easier to remember)
For what it's worth, the forks come out of the triple tees with just a bit of coaxing. You DO NOT have to remove the shields or the upper or lower clamp.
Also the top cap unscrews from the tube easily as well. Note: in the absence of the correct metric wrench for the top cap...a 15/16 std. works perfectly.

Once I got the cap loose and slid the tube down a bit, i poured, what I expected to be slightly dirty fork oil into the drain pan. That is not what came out of the left fork... It looked like "black water", yeah the kind that comes out of a trailer holding tank. It was watery thin and very deep grey in color.
The right side still had some of the blue color of the original oil left and the viscosity was much closer to what I would have expected.

Here's the question...Is one of these forks set up to handle compression damping and the other set up for rebound damping? That might explain the completely trashed oil in the left fork if that is the one that handles compression damping.

Also, might want to change and upgrade your own fork oil given the above results....just sayin'
Kirk
 
Yes, one leg has compression damping; the other has rebound damping.

Stephen
 
After finishing the job, I can report that this is not a difficult job and only requires removal of the top cap, spring and spacer. I replaced the spring and spacer with Matris components but that is not necessary.

600 ml per fork of a good quality 5w fork oil, gives almost exactly the required 110 mm air gap between the fluid and the top of the outer tube. I was able to compress the spring enough by hand (difficult but not impossible) to get the top cap screwed back on.
The left fork controls the Rebound damping, while the right fork handles the Compression damping. FWIW, the rebound damping is significantly more aggressive than the Compression.

I'm going to add this oil change to the maintenance schedule every 10,000 miles...or about the time frame to replace a front tire.
 
Touringman,

Your post of 6/27 questions whether the LEFT fork is the compression dampener due to the terrible condition of the used fork oil. But then, in your post of 6/29, you state that the LEFT fork is the REBOUND dampener. Is this correct? If so then I guess we don't have any idea why the left fork's oil was in such poor condition.

Please share your evaluation of the Matris spring and spacer kit. Were you having any specific issue with the performance of the forks in the past? If so, did the kit correct or reduce the severity of the issue? Do you feel the kit is worth spending the money for it?

Last question: When you re-installed the stanchion cap (compressing the spring in the process), did you do this with the fork stanchion free from the bike or did you do this after putting the stanchion back in the triple trees? I would think it easier to compress the spring and thread the caps in when the stanchions are pinched back in the triple trees. I have not done this service yet so I'm speaking without any experience.

Thanks,

Den.
 
Touringman,

Your post of 6/27 questions whether the LEFT fork is the compression dampener due to the terrible condition of the used fork oil. But then, in your post of 6/29, you state that the LEFT fork is the REBOUND dampener. Is this correct? If so then I guess we don't have any idea why the left fork's oil was in such poor condition.


Hey Dennis, on 6-27 I was hazarding a guess on which stanchion did what. My initial guess was based on what I knew from experiences was a "too soft" spring; thinking that compressing the cartridge would be harder on the oil than rebound control. I was wrong. Once the old oil was drained and the new oil in place, one "pumps" the cartridge rod to expel trapped air.. it is very obvious very quickly which is which. As to why the rebound damping fluid was so bad...I haven't a clue.


Please share your evaluation of the Matris spring and spacer kit. Were you having any specific issue with the performance of the forks in the past? If so, did the kit correct or reduce the severity of the issue? Do you feel the kit is worth spending the money for it?


The Matris spring and spacer kit has solved the issues quite nicely. The Matris spring is NOT progressive wound; it is linear, and is a huge improvement over the soft, progressive stock spring. The brake dive is significantly reduced, the nervousness at speed is gone and the tendency the bike had to push wide in a corner while applying power is also a thing of the past. This to me was a safety issue as well as being annoying. Note: the bike carries the Matris emulsion rear shocks as well and I ride two up most of the time. Having had sport bikes and sport tourers in the past I was aware almost immediately that the front fork springs were too soft and the overall damping could not keep up with the motion of the forks. The large amount of brake dive when applying the brakes hard was a dead give away. In addition the front end felt "nervous" at highway speeds unless the road surface was glass smooth. I never felt out of control, but the I knew the front end could be better and deliver more precise information on what the tire was doing.


Last question: When you re-installed the stanchion cap (compressing the spring in the process), did you do this with the fork stanchion free from the bike or did you do this after putting the stanchion back in the triple trees? I would think it easier to compress the spring and thread the caps in when the stanchions are pinched back in the triple trees. I have not done this service yet so I'm speaking without any experience.


This is the third set of forks I have "re sprung", and easily the most difficult. The job is not hard just harder than any other bike I have messed with. The 1400 REQUIRES a "thin" 19mm wrench, that must be inserted between the top of the spring spacer and the cap, to hold the rod still while the cap is secured and torqued. One CANNOT do this by hand as the rod will simply spin and the cap will not thread securely in place. I know. I tried. I failed.
The only way to do this without the $116.00USD tool is to grab the spacer, and pull down HARD!, thereby compressing the spring, while shoving the thin wrench onto the square boss on the rod between the top of the spacer and the bottom of the cap. Note: eat lunch first, that is one stiff spring. For more details and pictures please refer to the service manual.
I did this with the stanchions OUT of the triple trees. My reasoning is that is easier to fill and measure the oil level with the stanchions standing straight up. I prefer to measure the air gap rather than relying on a set amount of oil. This cannot be done without the stanchions out of the trees. Also, after wrestling the 1400 spring kit and wrench, I cant imagine doing that with handle bars etc in the way.
One last note. the Matris kit requires some modifications to the hard resin spacers for them to work. This is easily accomplished with a Dremel Tool and about 20 minutes of patience. The spacer has a "nipple" on one end that is supposed to fit into one end of the spring..., it doesn't. The nipple needs to be ground down a bit in diameter to fit in the spring. Also the hole in the middle of the nipple is too small to go over the square boss on the rod. It needs to be opened up a couple of mm. Again easily done with a Dremmel.
 
For more details and pictures please refer to the service manual.
Thanks for the details Touringman.

I looked at the "Service Manual" (part # B043157). I did not see a useful illustration of the front forks showing all the internal parts with associated part names, such as I would find in any respectable service manual I've used in the past. Additionally I thought their use of vernacular totally confusing. It seems obvious that a technical manual written in Italian was translated by a NON-Technical person. Numerous references are made to the same parts under different (often nondescript) names. Triple trees are simply called "plates"; they seem to have gotten stanchion correct; "upper cap", why the modifier, there is only one cap on the stanchion; further down, while draining the oil they refer to the stanchion as the "sleeve", and call the lower fork tube the "wheel holder sleeve". at least that one is easily followed. Next they mention the fork piston and its removal, in the next sentence they refer to the same item as the "pumping member".

There are others but I've made my point. I'll read the manual a few more times and slowly work my way through the parts myself using a notebook and camera. They do include some nice photographs and lots of pictures of "special tools" which is helpful. Right now I have 7000 miles on my bike so I'll wait until this winter to pull the forks apart and change the oil. I'll have my thin 19mm combination wrench in my hand thanks to your advice.

I wonder if the nasty broken down oil you found in the rebound dampening leg was in such bad shape because, as you point out, the rebound dampening is substantially stronger than the compression dampening. This may have just destroyed what Moto Guzzi put in there, perhaps an inferior or insufficient fork oil considering its work load?

My riding setup is quite different than yours, I ride solo mostly and load no more than 50 lbs of gear (I like to go camping and that gear adds ~15-20 lbs). Plus I'm light myself at 155 lbs. I've ridden my Cali Touring above 90 mph several times and while I do prefer to ride below 90 more, I can't say I felt it to be squirrelly or nervous. So I have to wonder if this condition might have been brought on by having the stiffer rear suspension (Matris emulsion rear shocks) coupled with the soft front suspension. I also tried to feel the pushing wide while cornering under power effect but did not notice it, though I will say that I can't lean this bike over while cornering any where as much as I can my BMW, and that is a bummer.

I do agree that the front forks are mushy, dive badly upon hard breaking and lack some "road feedback" that I get much more accurately from my BMW. But then my 1973 R75/5 BMW is a completely different kind of machine, almost half the weight, more ground clearance and very different suspension geometry.

If you know of a different or better Service Manual, please make mention of it. In the mean time enjoy your newly improved handling Cali. And thanks for sharing so much.

Den.
 
I installed the Matris spring kit yesterday so I wanted to revisit this post as it provided valuable information on how to go through the process. Some observations:
  • My right fork (as seen when sitting on the motorcycle) had the nasty grey watery oil, just as described in the original post. Left fork had the blue oil which looked as expected.
  • Matris spacer is made of aluminum or some similar kind of metal, and has a plastic cap on bottom end that is supposed to go over connecting rod's limiter (the thing that requires the 19mm thin wrench) and into the spring. The cap that came on my set would fit into the spring nicely but it wouldn't go over the rod limiter so I had to grind it down a bit with a Dremel and some sanding.
  • The rod limiter seems to serve as a preload adjuster, and as it comes with the bike it's screwed down the rod quite a bit (i.e. it's given more preload.) I found installation a lot easier when I unscrewed the limiter all the way to the top, and only then pull on the spacer while holding the rod in its uppermost position so I could slide the 19mm thin wrench and stop the spacer from going back over the rod. Once I secured it that way it was very easy screwing it down to a desirable level of preload (I left significantly less preload as the Matris spring is already a lot stronger than the one that came from factory.)
  • Right now I have Matris springs and original rear shocks on my Touring. It's noticeable (but not by too much) that the front is stronger than the rear so it will definitely be better when paired with Matris rear set, but even as it is it gives a much more stable ride and confident handling. I live in Bay Area and the roads can get pretty bad, especially bumps and holes on freeway ramps where you have to steer as well as pick up speed. My Cali1400 is now much more stable in these situations, and by the second ramp I was already used to the new handling. Smaller holes and bumps are almost unnoticeable now, and going over them is uneventful which is of course great.
Overall I'm very happy I installed this set. I don't understand why they would ship the set with spacer caps that need to be modified, but other than that the installation was easy and the effects are worth many times more than the price.
 
I installed the Matris spring kit yesterday so I wanted to revisit this post as it provided valuable information on how to go through the process. Some observations:
Hmmm, well, per the instructions, the aluminum spacer sits down onto the spring and locks in. You do not need to modify anything. Why didn't you ask me direct earlier?
 
Hmmm, well, per the instructions, the aluminum spacer sits down onto the spring and locks in. You do not need to modify anything. Why didn't you ask me direct earlier?
I don't understand what you mean by it sits down onto the spring and locks in? It does sit down but in order to lock it in you have to screw in the top cap of the fork, no? And that requires pulling the spacer down while keeping the hydraulic rod all the way up so you can screw the top cap in.

It's never too late for new advice though :)
 
I don't understand what you mean by it sits down onto the spring and locks in? It does sit down but in order to lock it in you have to screw in the top cap of the fork, no? And that requires pulling the spacer down while keeping the hydraulic rod all the way up so you can screw the top cap in.
Yes, they require a spring compression tool like THIS one.
Matris is VERY good at plug and play. If you have to modify, then it is most likely user error. Always better to ask.
 
Yes, they require a spring compression tool like THIS one.
Matris is VERY good at plug and play. If you have to modify, then it is most likely user error. Always better to ask.
Oh I see, that's a very nice tool and yes it'd definitely help with the installation. The part that I had to modify is the plastic spacer - the inner hole diameter is simply not big enough to let the hydraulic rod through - it came like that from the factory for some reason.

-- Sorry, the spacer is aluminium but it has a plastic cap with a hole where it meets the spring.
 
The part that I had to modify is the plastic spacer - the inner hole diameter is simply not big enough to let the hydraulic rod through - it came like that from the factory for some reason. -- Sorry, the spacer is aluminium but it has a plastic cap with a hole where it meets the spring.
OK, can you send me any notes or pictures (hopefully) so I can let them know? Send email to: Todd at GuzziTech.com
 
OK, can you send me any notes or pictures (hopefully) so I can let them know? Send email to: Todd at GuzziTech.com
I didn't save any pictures or notes unfortunately... I found a tutorial/writeup on how to replace the springs either on this site or C1400 owners forum, and the OP said he had to modify the plastic cap of the spacer too, except in addition his plastic cap couldn't fit into the spring either so he had to grind that part of the cap too.

Do you happen to have a picture of the plastic cap, possibly from your set of springs? If we could see a photo of it it'd be a lot easier for me to explain where the problem is.
 
One last note. the Matris kit requires some modifications to the hard resin spacers for them to work. This is easily accomplished with a Dremel Tool and about 20 minutes of patience. The spacer has a "nipple" on one end that is supposed to fit into one end of the spring..., it doesn't. The nipple needs to be ground down a bit in diameter to fit in the spring. Also the hole in the middle of the nipple is too small to go over the square boss on the rod. It needs to be opened up a couple of mm. Again easily done with a Dremmel.

Todd, I can confirm what WroomWroom is talking about. I too had to "slightly modify" the spacers that were sent with the Matris Kit for the 1400. The included spacers are a hard resin like molded plastic sort of material. The spacers that came out of the stocker were anodized aluminum.
The spacers supplied with the springs were a couple of mm too small on the inner hole, to slip over the boss for the 19mm wrench, and a couple of mm too large overall to "pop" into the spring and sit flush on one end. It took all of 10 minutes per spacer to adjust the sizing. I wondered at the time if I had gotten a set of spacers for a different bike (Norge perhaps), but they were so easy to modify, I really didn't think twice about just fixing the minor sizing issue.
All this said, those springs are a huge improvement over the soggy stockers, and well worth the $$ spent!
Kirk
 
I realize that this thread is a year and a half old, perhaps it is because only a few members have installed this Matris Fork Spring Kit. In preparation to installing my kit I measured my 19mm open end wrench: it is 9mm thick. I went shopping, found a 7mm thick wrench and bought it. Will my new 7mm thick wrench be "Thin" enough to do the job Touringman?

Also, Todd, have you anything definitive to state about the spacers provided with this kit when installing them in the Cali 1400 forks, pertaining to suggested modifications? This thread has two people stating that the spacers must be modified to get them to fit: 1) into the spring and sit flush, and 2) over the boss. Your final statement in this thread was that no modifications should be required.

Regarding the "spacers" in question, I looked at my kit and indeed, the instructions state that, what they call the spacer (part "B"), fits into the provided springs. Mine do, so that much does not require a comment, The question remains however whether these spacers will fit over the "boss". Since I have not yet disassembled my forks I can't yet say if mine will work without modification. I can say that the inside diameter of the spacers in my kit are exactly 21mm wide. I'll measure the diameter of the "boss" when I do the work.

One other matter is the fact that my kit includes TWO bottles of fluid, yet the list of materials only mentions ONE fluid bottle. The first, larger (1 liter) bottle is obvious, it is manufactured by Motorex and labeled as 10 W Fork Oil. The second bottle is about half the size or less, has no markings, is red in color and of a very light viscosity. The instructions or list of kit materials makes no mention of this fluid. I'm dead in the water as to it's purpose. Perhaps it is a cleaner???

Note: The provided instructions refer to the black aluminium tubes plus the attached white plastic piece as "the spacer" or "Part B", However, it is this white plastic piece to which the above posters call the "spacer" and the item to which they claim a modification is necessary. As seems to be the case often, these Italian instructions are vague and the nomenclature sometimes misleading if not imprecise. It is this white "collar" that I have observed fitting precisely inside the Kit's provided springs, even though the instruction's illustration does not show the white collar at all.

Obviously I will provide some follow up post once I get my forks disassembled.


Thanks.
 
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(Dennisj.....One other matter is the fact that my kit includes TWO bottles of fluid, yet the list of materials only mentions ONE fluid bottle. The first, larger (1 liter) bottle is obvious, it is manufactured by Motorex and labeled as 10 W Fork Oil. The second bottle is about half the size or less, has no markings, is red in color and of a very light viscosity. The instructions or list of kit materials makes no mention of this fluid. I'm dead in the water as to it's purpose. Perhaps it is a cleaner???)

My understanding is that the smaller bottle is also Motorex Fork Oil and supplied because the forks require more than a liter. Touringman above says 600ml per leg.
 
My experience with the Matris Cali1400 Fork Spring Kit
  • Provided Fork oil: 10W, red color and they give you "just enough" of it to do the job, so, DON"T SPILL ANY OF IT! You might consider buying an extra liter of it (Motosport.com, $25 shipped to my door). Tip: When filling the fork tube with fluid be sure to push the stanchion all the way down into the lower fork tube, there is a port drilled in the stanchion, which is exposed when extended, and the fluid will run out onto the floor, and over your shoe, if you don't keep the stanchion fully seated in the fork leg. I learned this through first hand experience.

  • Moto Guzzi workshop manual B043157 page 306 specifies an air gap of 110mm (with a nice graphic illustration), but Matris specifies a 105mm air gap in their instruction guide provided with the kit. It's their kit, I used their spec.

  • The Matris kit includes the chrome spring, a black aluminum tube (the "preload spacer") and a white plastic flange that goes between the spring and the preload spacer. This plastic flange is the subject of much discussion in this "Nasty Fork Oil" thread. The (uncompressed) length of this assembly (spring, flange, and spacer) is about 18 inches long, the same length as the original Moto Guzzi assembly.

  • The inside diameter of the flange is too narrow to pass over the piston rod "boss" or shoulder, by about one millimeter. This requires some method of removing a total of one millimeter of material from the inside dimension of this flange. As the others suggested, I used my Dremel with a course sanding drum to do it, very messy, not to mention aggravating.
General notes:
  • You need to remove the calipers, front ABS sensor cable, front wheel and fender to begin this task.

  • I loosened the fork tube caps, using a 24mm socket, while the forks were still mounted in the triple trees (always called "plates" in the workshop manual.) Just crack them loose don't try to remove the caps. These caps will slide down through the triple trees with the stanchions.

  • The fork tubes (stanchions) slide down through both triple trees once all (6) pinch bolts are removed. I used metal wedges to open the pinch gaps a little to make stanchion removal a little easier. A little persuasion on the fork tube caps with a wooden dowel is helpful, gently though.

  • This is a great time to lubricate the Steering Shaft bearings with grease and check/set the torque on the steering shaft.


    Fork piston shaft diameter Matris spacer diameter
 

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