Now onto the forks

[FuelCooler]

(FuelCooler)

Ratchethack, dlaing and others,

Do you want to start a new thread (I know this stuff has been covered before) or can you suggest an existing one to attach it to?

I would like to continue with the fork /shock topic but we will bog down this gearbox thread if we don't do something quick!

 

:!: The following is the birth of a new topic thread that started as a hi-jack of the 'Re-sealing the 6 speed. As Ratchethack points out, I am the hi-jacker and the hi-jackee. I hope this isn't worse then leaving it in the original post! Oh well here goes.....

 

Front also feels harsh over sharp bumps but doesn't bottom.

 

Ooops,

I didn't mean they never bottom. They are using full stroke (they will bottom if called upon, but they do make a 'pissst' sound on low speed compression (like slowly riding over a 1.5 inch curb). Never heard that before on Showas or KYBs. I will measure the oil height on dissassembly.

 

I actually set my air gap (after setting sag and getting a rough setting for comp. damping) by a test very similar to what you asked me to do, braking over a bump(s) and even setting down wheelies firmly (not slamming). I have a very good feel for what I want and start with the level low (big gap) and work my way up (less gap). I am very tempted to start at 110mm.

I am also curious about my fork springs. Stock they should be way softer then my numbers indicate, so someone could have set them up already.

 

I guess you and Ratchethack werent satisfied with rear spring alone and purchased shocks?

[Guest ratchethack]

:!: The following is the birth of a new topic thread that started as a hi-jack of the 'Re-sealing the 6 speed. As Ratchethack points out, I am the hi-jacker and the hi-jackee. I hope this isn't worse then leaving it in the original post! Oh well here goes.....

Ooops,

I didn't mean they never bottom. They are using full stroke (they will bottom if called upon, but they do make a 'pissst' sound on low speed compression (like slowly riding over a 1.5 inch curb). Never heard that before on Showas or KYBs. I will measure the oil height on dissassembly.

 

I actually set my air gap (after setting sag and getting a rough setting for comp. damping) by a test very similar to what you asked me to do, braking over a bump(s) and even setting down wheelies firmly (not slamming). I have a very good feel for what I want and start with the level low (big gap) and work my way up (less gap). I am very tempted to start at 110mm.

I am also curious about my fork springs. Stock they should be way softer then my numbers indicate, so someone could have set them up already.

Steve, I'm a little puzzled, but coupla random fliers here that might serve to un-puzzle this a little.

 

Your laden and unladen sags and riding weight don't seem to line up with an ability to bottom the fork unless you've got a significantly out of line AIR GAP on the low side (and hence, low oil volume). You indicated that you set the AIR GAP, but didn't say wot level you set it, then said y'er tempted to start at 110 mm, so wot DID you start with??

 

It seems that the stock-issue Marz 040 fork was shipped with at least two possibilities of diferent spring rates. The ones I got were ~.6 kg/mm. Others seem to be in the vicinity of .9 kg/mm. There may be other possibilities, so as a rule, lacking an ability to accurately measure spring rates directly, and not knowing if the PO replaced them, best look at sag measurements as you've done, and figure out what rate fits your sags. By your sag measurements and riding weight, I'm guessing yours would be around 1.0+ kg/mm, which should be somewhat on the stiff side. If your AIR GAP is set correctly, you should be pretty good overall on the front end, for "sporting" stiffness. If you bottom out at all, it should only be under the most extreme circumstances. Sounds like you might be there or close to there. Getting a read on the AIR GAP would clarify the picture considerably.

 

Now the 'pissssst' sound over a bump has really got me buffaloed, but it might explain an ability to bottom the fork prematurely, even with correct AIR GAP. The only thing I can imagine is a bad o-ring at a fork cap, which would be easy enough to diagnose and rectify. If you made a raised "cup" around the fork caps out of tape with soapy water in the "cup", you could bounce it with the engine off to track down a leak at the caps. I'd jump on that one PDQ.

I guess you and Ratchethack werent satisfied with rear spring alone and purchased shocks?

Steve, I chose the route I took based on the principle, "replace the worst link in the chain first". In my case it was worthless limp-noodle fork springs. After that, it was so much better , it was a brand-new world, even with shock preload cranked up way too high like you've done to get laden sag right, even though unladen sag was way out o' range on the low side. Couple years and 20K miles later, even though in a "perfect world" (wich I ain't found yet, BTW ) it would've been long overdue, I figured a new rear spring would be an option, and this in itself would make it a Brand New World, Part II, but upgrading a spring on a well-worn, mediocre shock to begin with didn't make much sense. I could well justify the new custom Wilbers Modell 629 with rebound and hi/lo speed comp adjustability, length to my spec. (+5mm over stock) and 95 N/mm spring to order. Yep, it WAS a Brand New World, Part II.

[richard100t]

If you can hear a hissing sound coming from your forks over the engine noise I'd say theres a problem there.

[FuelCooler]

Steve, I'm a little puzzled, but coupla random fliers here that might serve to un-puzzle this a little.

 

Your laden and unladen sags and riding weight don't seem to line up with an ability to bottom the fork unless you've got a significantly out of line AIR GAP on the low side (and hence, low oil volume). You indicated that you set the AIR GAP, but didn't say wot level you set it, then said y'er tempted to start at 110 mm, so wot DID you start with??

 

Yeah, I wasn't clear there.

I have never been in these forks. They could have olive oil in them, set at 153.5mm! What I meant to say was when I set up my forks on other bikes I start out with a big air gap, but am tempted to start at 110mm on this bike which, from what I have read here, would be close. I may sound like a fool (and infact may be one) but I am new to using forums! My ideas about what is going on with the sag and spring is exactly what you (Ratchethack) and dlaing advised. I just want make sure I am not missing something that is specific to V11 set up (like the noise).

About the bottoming. It is seldom (remember that I ride on NJ pot holed and patched roads) and not severe unless I smash something big.

 

Now the 'pissssst' sound over a bump has really got me buffaloed, but it would explain an ability to bottom the fork prematurely, even with correct AIR GAP. The only thing I can imagine is a bad o-ring at a fork cap, which would be easy enough to diagnose and rectify. Seems to me that with a raised "cup" around the fork caps made of tape with soapy water in the "cup", you could bounce it with the engine off to track down a leak at the caps. I'd jump on that one PDQ.

 

I figured it wasn't normal but the only other guy I have talked to has Ohlins on his V11. Great idea for finding the leak. Thanks.

 

Steve, I chose the route I took based on the principle, "replace the worst link in the chain first". In my case it was worthless limp-noodle fork springs. After that, it was so much better , it was a brand-new world, even with shock preload cranked up way too high like you've done to get laden sag right, even though unladen sag was way out o' range on the low side. Couple years and 20K miles later, even though in a "perfect world" (wich I ain't found yet, BTW ) it would've been long overdue, I figured a new rear spring would be an option, and this in itself would make it a Brand New World, Part II, but upgrading a spring on a well-worn, mediocre shock to begin with didn't make much sense. I could well justify the new custom Wilbers Modell 629 with rebound and hi/lo speed comp adjustability, length to my spec. (+5mm over stock) and 95 Nm spring to order. Yep, it WAS a Brand New World, Part II.

 

This bike didn't get bad reviews for suspension in the tests I have read from 2000-2001 (even MCN), and with the correct springing should be pretty good (if the suspension fluid is fresh). New fluid for both ends is on my list but I would love to spend the $$ on the same shock as Ratchethack with the +5mm length.

Did you ever replace the shock fluid in the stock shock? If so what did you use?

Thanks for your patience guys,

Steve

[dlaing]

The important details

Thats exactly what I meant about the disassembly.

I will update my edit for clarity with your quote, thanks again BrianG.

I will hi-jack my own thread for a post or two!

Here is what I have feel wise:

Bike squats and weaves a bit while turning under hard acceleration (especialy high speed).

Rear feels harsh over sharp bumps but doesnt feel like it bottoms.

Front feels vague during all phases of the turn (turn-in to exit).

Front also feels harsh over sharp bumps but doesn't bottom.

Bike gives a decent freeway ride.

 

Here is the set-up:

Spring rates are unknown but the rear appears to be stock white Sachs.

Last fork / shock service unknown. Suspension fluid type / quantity unknown.

185 lbs geared-up rider and 1/2 tank of fuel.

Rear sag - 6mm bike only

-34mm laden

Front sag -25mm bike only

-35mm laden

Rear Rebound -13 clicks out

Rear Compression -23 clicks out

 

Front Rebound - 9 clicks out

Front Compression - 12 clicks out

 

Forks through upper clamp 10mm.

Bitubo damper set minimum.

 

I want to change both fork and shock fluid before I condemn the chassis.

I am 100% an air gap method guy.

To be honest I havent done much but back the compression out for better compliance but I feel it is low speed compression damping (fork and shock) / combined with a bit too much rear sag that are causing my issues.

[dlaing]

Here is link to an essential PDF guide to fork fluid.

http://www.hrpworld.com/client_images/ecom.../pdf_3119_1.pdf

Generally I say go with a weight that makes you happy when the damping adjusters are about one third of the way out.

The beauty of the Marzocchis with compression damping adjuster on one fork and rebound damping adjuster on the other fork is that you can put different weights in each fork, if needed.

You are at "Front Rebound - 9 clicks out

Front Compression - 12 clicks out"

Assuming that is 10W fork oil, you will probably want to go with something a little thinner like 7W, but as you see from the PDF, one makers 5W can be thicker than anothers 7W.

Look for a fluid with not much variation between viscosity at various temperatures, a cSt of around maybe 15-25 at 40ºC

Excellent choices might be :

Maxima Racing Shock Medium

Silkolene Fork 5w (Penske)

Ohlins (stock)

Penske Lightweight Shock Fluid

Torco MFO 10w (VI 260)

Bel-Ray HVI5w

Redline LightWeight 5W (Yellow)

Other good choices may be:

Spectro Cart. Fork 85/150

Motul Fork 5-10

Bardahl Fork Oil 5w

Bilstein Shock Oil (stock)

But as always, YMMV

Also, from your latest description, you might try raising the fork fluid level about 5 or 10mm from what it is, but paying attention not to stray too far from Ratchet's recommended level.

But once again, you need a stiffer spring on the rear.

Maybe about a 475-500# spring

Maybe even 525# if you ride motocross in NYC

But seriously, if you face a lot of pot holes, you might consider an Ohlins shock. The stock Sachs shock is known for the aluminum eye cracking, and it has 60mm of shock stroke vs. 70mm for the Ohlins.

For nice twisty roads you don't need much travel, but for potholes, the more travel the better.

I ordered a Penske Shock with 70mm stroke.

Note that rear wheel travel is roughly equal to twice the shock stroke length.

I had tried a 475# spring on my Sachs and it was just a little too light for my 210 lb plus leather, boots, helmet, etc.

For the Penske, I will try a 525# spring.

If it does not work out, I may try a HyperPro progressive spring for the rear.

If I lived in NYC, I would go even heavier.

New Jersey is more variable...

Ratchet is a lot closer to your weight than I am, so he will have a better idea what spring weight to go with.

[Guest ratchethack]

This bike didn't get bad reviews for suspension in the tests I have read from 2000-2001

Reviews?! Pardon my skepticism. Now this is just me, and I haven't read any o' the bike rags f'er years. But I'd trust a "moto journalist's" comments on suspension in an "evaluation" or "test" about as far as I can throw a Guzzi over the back fence. In the many hundreds of reviews I've read in the past, any mention of correct, close, ballpark, or even same planet sag settings for the tester were for the most part non-existent. Now I'm sure there have been exceptions to this (somewhere ). OK, I do know of a very few. But generally speaking, when it is mentioned at all, some of the comments I actually HAVE read on setup before road testing have been so out o' whack that IMHO correct setup for a "road test" by a moto rag may generally be assumed to be anywhere between poor, non-existent, or (if possible) worse than non-existent unless clearly and credibly documented to be otherwise. Any connection at all between correct setup and road manners, handling, and even safety seems to've historically been about as poorly understood by professional moto "journos" and editorial staffs as it has been by the garden-variety newbie moto squid.

 

One imagines a "track test" scenario: The crew shows up late, everyone's hung over, the tires seem to have some air in 'em, it sounds like there's some gas in the tank, and you've got 3 minutes of track time left on the clock. Now get it off the truck and get going!

Did you ever replace the shock fluid in the stock shock?

Never did. As mentioned, the Sachs-Boge shock, having given a faithful, however sadly misplaced and under-appreciated life of service while continually being asked to give more than it had to give , was on an "early retirement" plan, which took this out o' consideration.

[Dan M]

Hey Ratch, Did you ever get a reply from Marz on the manual for the 40mm units?

[Guest ratchethack]

Hey Ratch, Did you ever get a reply from Marz on the manual for the 40mm units?

Yeah I did. I'd tried to elevate the status of my inquiry by mentioning the info I was after would be posted on a prestigious International moto Forum with a vast clientele of First Class Most Special Fellows -- Guzzisti! They responded by giving me an email address of some guy that promptly bounced. I sent another request with a recap of the experience. No apology, but something about must be having "issues" with the server, and here's a phone number.

 

I simply loathe "issues", much preferring "problems", which seem far less complicated.

 

At least when you deal with "a problem", there's some expectation of "a solution".

 

I haven't got a Round TUIT, but y'er more'n welcome:

 

"Try calling Johner Faulkner at 661.257.6630 extension 126"

[FuelCooler]

 

Also, from your latest description, you might try raising the fork fluid level about 5 or 10mm from what it is, but paying attention not to stray too far from Ratchet's recommended level.

But once again, you need a stiffer spring on the rear.

Maybe about a 475-500# spring

Maybe even 525# if you ride motocross in NYC

But seriously, if you face a lot of pot holes, you might consider an Ohlins shock. The stock Sachs shock is known for the aluminum eye cracking, and it has 60mm of shock stroke vs. 70mm for the Ohlins.

For nice twisty roads you don't need much travel, but for potholes, the more travel the better.

I ordered a Penske Shock with 70mm stroke.

Note that rear wheel travel is roughly equal to twice the shock stroke length.

I had tried a 475# spring on my Sachs and it was just a little too light for my 210 lb plus leather, boots, helmet, etc.

For the Penske, I will try a 525# spring.

If it does not work out, I may try a HyperPro progressive spring for the rear.

If I lived in NYC, I would go even heavier.

New Jersey is more variable...

Ratchet is a lot closer to your weight than I am, so he will have a better idea what spring weight to go with.

 

Thanks for the fork oil list, the only one I have used is the Belray HVI, but this time I may try another.

I have read a bunch of your comments on suspension set up (as well as Ratchethacks) and it looks like you guys have got it nailed.

One thing I find reassuring is that sag recommendations don't seem to have changed at all from a Keith Perry (Team Valvoline Suzuki circa 1992) seminar I attended. I always liked the feel of 20-25mm rear and 35mm front and if I change the rear spring, as you both advise, it looks like I would be in my happy place again. But I do see a move toward progressive springs that were once frowned upon in the early to mid 1990's. But if they work better, why not use them?

The roads can be so bad here that I actually knocked the headlight out of my R1150R on a pot-hole, it was dangling by the wires!

[FuelCooler]

Reviews?! Pardon my skepticism. Now this is just me, and I haven't read any o' the bike rags f'er years. But I'd trust a "moto journalist's" comments on suspension in an "evaluation" or "test" about as far as I can throw a Guzzi over the back fence.

 

Point taken. Hit or miss with them, and you don't know which until you see it for yourself.

 

Never did. As mentioned, the Sachs-Boge shock, having given a faithful, however sadly misplaced and under-appreciated life of service while continually being asked to give more than it had to give , was on an "early retirement" plan, which took this out o' consideration.

 

Now this surprises me after your 'fork oil change' comments on other threads!

 

You and I Ratchethack, are so close in weight that I bet I would love your exact set up on my bike, and I could save myself alot of grief and a bit of money by just doing exactly what you have right now. And I just might.

Was there an additional charge for the extra length on your shock? IIRC you stuck with the stock 60mm stroke. And how long did it take from order time to your door?

[Guest ratchethack]

Now this surprises me after your 'fork oil change' comments on other threads!

Eh? Wot's the difficulty?

 

I figure the Marz forks are just starting their looong career. The Sachs-Boge shock was put out to pasture early as planned, before oil breakdown could have much of an effect, with no expectations of coming back out o' retirement.

Was there an additional charge for the extra length on your shock? IIRC you stuck with the stock 60mm stroke. And how long did it take from order time to your door?

They're both config-to-order and build-to-order. Yes, stock 60 mm stroke. No additional charge for any design spec you choose, and you can choose too many for me to list or remember. I think turn-around then was about 4 weeks, if memory serves. Todd Eagan at GuzziTech can give you the latest poop.

 

Can't say enuf good stuff, but beware the USD against the Mark lately.

 

http://www.guzzitech.com/WilbersSuspensions.html

[richard100t]

Eh? Wot's the difficulty?

 

I figure the Marz forks are just starting their looong career. The Sachs-Boge shock was put out to pasture early as planned, before oil breakdown could have much of an effect, with no expectations of coming back out o' retirement.

 

They're both config-to-order and build-to-order. Yes, stock 60 mm stroke. No additional charge for any design spec you choose, and you can choose too many for me to list or remember. I think turn-around then was about 4 weeks, if memory serves. Todd Eagan at GuzziTech can give you the latest poop.

 

Can't say enuf good stuff, but beware the USD against the Mark lately.

 

http://www.guzzitech.com/WilbersSuspensions.html

Uh oh did you say the dollar isnt doing well against the mark? I know our currency is pretty bad but its not out of circulation just yet

[dlaing]

Todd Eagan at GuzziTech can give you the latest poop.

http://www.guzzitech.com/WilbersSuspensions.html

Guzzitech will also be offering YSS shocks.

YSS offers more choices in mono shocks with with a wider range of prices than Wilbers.

Are they a better deal? I don't know.

But I think they are worth investigating.

Before hearing about YSS, I would have gone with Wilbers, but went with Penske because I wanted more travel. For about the same money I traded High Speed compression adjustability for a few mm of travel. Was it worth it? I'll probably never know for sure.

But now the YSS are looking like an excellent choice.

Some of the models have two way damping adjusters and some three way.

Some are milled billet.

Some are available in 10mm length increments and some can come any length.

If I had not ordered the Penske, I would have taken a good look at the billet models with any length availability.

Here is my list of lengths that I think will work well...in MY order of preference.

eye to eye 286mm and shock travel of 70mm (This is what Ohlins specifies for the Guzzi  V11 spine frames)
eye to eye 284mm and 68mm travel
eye to eye 282mm and 66mm travel
eye to eye 280mm and 64mm travel
eye to eye 286mm and somewhere between 64 and 70mm travel, with me favoring more travel.
eye to eye 284mm and somewhere between 63 and 68mm travel, with me favoring more travel.
eye to eye 282mm and somewhere between 62 and 66mm travel , with me favoring more travel.
eye to eye 280mm and somewhere between 60 and 64mm travel , with me favoring more travel.
eye to eye 278mm and somewhere between 59 and 62mm travel , with me favoring more travel.
(278/60 is about what the Sachs is)

I think most people would be happiest with something around eye to eye 280mm and somewhere between 60 and 64mm travel...YMMV.

 

I suspect that if you get outside any of these ranges you may risk the suspension binding, the shaft angle could be too much, ride height could be wrong, and comfort could be compromised.

[Guest ratchethack]

I think most people would be happiest with something around eye to eye 280mm and somewhere between 60 and 64mm travel...YMMV.

 

I suspect that if you get outside any of these ranges you may risk the suspension binding, the shaft angle could be too much, ride height could be wrong, and comfort could be compromised.

FWIW, the stock Sachs-Boge measures 280 mm eye to eye and (yeah, I know this may seem like a contradiction ) it actually has a ~64 mm stroke, when compressibility of the "shock donut" is taken into consideration, as is standard practice by mfgr's. To tell the truth, my memory may be slightly fuzzy on this but I do recall that when I placed my Wilbers shock order, there was some back-and-forth discussion on this and the result of confirming my order was that I ordered (and was delivered) a stroke identical to the Sachs-Boge.

 

Again, when ordering from Wilbers, it's config-to-order and build-to-order. You can specify any eye to eye length and any stroke wanted at no extra cost.

 

IMHO the stroke of the shock can vary around a few mm without much of any significance to the way it works on the road. More important than this are many other things: The spring rate, the way it damps, and ride height, as determined by eye-to-eye length. Keep in mind that stroke and changes to eye-to-eye length have an almost exactly double effect at the spindle. When I ordered 285 mm eye-to-eye, I was going for a 10 mm increase in ride height.