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hard hitting forks


renato

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Guest ratchethack

Have you got your spring rates correctly matched to the load, and set your sags properly?

 

Since you've provided ZERO basic information to work from, (making your request unanswerable) I suspect not. :o

 

In that case, you have some homework to do, my friend. (Though we're all most pleased to help, you have to do your part. I'm afraid no one here can do it all for you). :huh2:

 

May I most sincerely -- and for the sake of getting the most out of your fork -- most wholeheartedly and enthusiastically recommend starting here:

 

http://www.strappe.com/suspension.html

 

http://www.racetech.com/articles/SuspensionAndSprings.htm

 

and for final setup, this page on this site:

 

http://www.peterverdonedesigns.com/oilheight.htm

 

Hope this helps! :race:

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Guest ratchethack
My guess is overexuberant fork oil change and no air gap... we could start a book on this :)

We could guess, speculate, and indulge in all manner of conjecture and miss the mark by a mile, or 2 miles, or 200 miles. :rolleyes: Hopefully, he'll come back after learning a few basics with something to work with as a starting point, and we'll soon be helping him on his way to a relatively low-cost, relatively low-effort, yet relatively magnificently performing fork. :thumbsup:

 

-- and then again. . . maybe not? :huh2:

 

For many, it seems that doing any amount of "homework" is well, punitive -- and it's simply not worth the effort. :(

 

And waddayagonna do? :huh2:

 

I'm just challenging you a little, Renato -- come on, let's play ball. It'll be well worth it, and you'll thank us some day soon -- I promise you! :race:

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The stock marzochi forks on a Guzzi are pretty poorly setup from the factory. The design of the forks is also a little weak. The compression adjuster does next to nothing as the compression dampning is only at the bottom of the stroke. Most of the stroke allows oil to blow out of the damper tube freely. This leads to a fork that easily blows thru the stroke and slams at the bottom into the one part of the stroke that actually has dampning. This can make you think your forks are too stiff when in fact they are too soft. One way to check to see if this is indeed what is going on is to tighten a tie-wrap around one of the tubes(skinnier inner tubes, aka the shiney ones) right under where the larger outter tube is. This tie-wrap will be push down the tube as the fork travels thru its stroke. Take a ride, and if when your done the tie wrap is at the bottom of the stroke you know the fork is blowing thru its stroke. If the tie-wrap did not move very far down the tube then you may have issues like too high an oil level in the forks or binding, etc.

Setting up these forks can be done in a few ways. A good place to start would be to get springs made for your weight and set the sag.

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Like Ratch says...

 

 

Have the forks been "serviced" lately? Over filling with fluid will make them stiff. Using too heavy of fluid will make them stiff. Etc. etc.

 

Good luck.

:stupid:

Of course Renato may weigh 100 pounds and he could have bought the bike from some guy who weighed 500 pounds and had them resprung to fit his fatness. But not likely.

Ratchethack can even give good advice about fluid level, if you just take his hard ball pitches. Don't let him brush you back out of the batter's box.

A common misconception is that one thinks the springs are too hard when in fact they are too soft and you are feeling the bottoming out action. The experience of most riders is that going to firmer than stock springs makes the front end more compliant with the bumps in the road.

There have been cases where the adjusters don't work right after re-assembly, so it may be a good idea to make sure they are adjusting. Set to maximum damping and see if it gets worse.

Another possibility when backing the compression adjusters off all the way is that the suspension could be packing down, as the rebound damping may be out of balance with the spring rate and the compression damping.

Another possibility is the forks aren't straight and they are binding.

All speculation that couldn't possibly help Renato, right?!?

Maybe we should tell Renato, 'Get a Goldwing!'

But I would recommend upgrading to the allegedly unreliably leaky Ohlins before telling him to do that.

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Ok,when i purchased her n i say her because she can be a *&%## sometimes but ya gotta love her, she rode great then it started getting stiff so i changed the oil with amsoil light fork oil, put in exactly what factory recomends (factory dealers man. dont ever buy one) and she rode perfect, i dont put much of a load on her since most of my riding was in nyc (pot holes the size of snake river canyon) i wieght about 180 pounds. anyhow then it started to ride hard again so i drained 1/4 oz and it made no difference. She does not bottom she just wont move much and at a stand still she only moves about 3 inches with all my wieght being forced down and recently the bushings are starting to go probabally due to the front end not working properly, or could that be due to hard braking, you do have to compete with cabs and buses in the city, hope this is enough, thank you.

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Guest ratchethack
Ok,when i purchased her n i say her because she can be a *&%## sometimes but ya gotta love her, she rode great then it started getting stiff so i changed the oil with amsoil light fork oil, put in exactly what factory recomends (factory dealers man. dont ever buy one) and she rode perfect, i dont put much of a load on her since most of my riding was in nyc (pot holes the size of snake river canyon) i wieght about 180 pounds. anyhow then it started to ride hard again so i drained 1/4 oz and it made no difference. She does not bottom she just wont move much and at a stand still she only moves about 3 inches with all my wieght being forced down and recently the bushings are starting to go probabally due to the front end not working properly, or could that be due to hard braking, you do have to compete with cabs and buses in the city, hope this is enough, thank you.

Renato, many here (including myself, I b'lieve) can help you. Knowing your weight is at least something to start with, but you've got a ways to go in providing pertinent information.

 

From your response, it appears that you didn't as much as look at the suspension setup links I provided above. If we're gonna get any further here my friend, you're gonna hafta break down and do that, otherwise we'll very soon be bogged down in pages of unproductive thrashing, and frankly, I'm gonna lose interest real quick -- though you'll no doubt continue to get lots of potentially misleading speculation and conjecture without end here, most of which will confuse you past the limit of both your patience and mine. . . . <_<

 

If you put in the factory recommended volume of fork oil without getting all the old oil out (very typical), you more than likely had it overfilled and/or mismatched right and left, which would potentially cause severe air spring effects at the bottom of fork travel and/or binding of the fork. If you look at the third link I provided above, the principle at work is explained very simply. The ONLY correct way to set air gap is to measure it directly from the top of the stanchions, as described -- and IGNORE the factory spec'd volume altogether.

 

The list of speculation, which very quickly begins wildly shooting off in all directions without a proper footing (having next to no information to start with), has already well begun. Believe me, it goes on forever -- just trust me on that one at least? <_< So already we need to back up the old speculation train to get on the right track with something far more basic, which is what I asked you to start with -- that being if you've installed springs correctly matched to your riding weight, and if you've adjusted the sags correctly! Please understand that if you continue to ignore this, no one here -- or anywhere else -- can help you set up your fork! We can't make assumptions here without risk of going off on countless rabbit trails to nowhere. If you don't have the slightest idea what you're dealing with in terms of spring rates and sag settings, preload, etc., any discussion about the operation of the damping (as opposed to dampening ;) ) will be of no value to you, and will have you confused, pissed off, and completely lost -- and very quickly, at that. :huh: Again -- The basics of fork setup are described in simple, straightforward language in the first two links I provided above.

 

We're getting somewhere, my friend, but not nearly as far -- or as quickly -- as we could be if you had a grasp of the basics. You've simply got to get ahold of the basic concepts to communicate what you're starting with and where you think you want to go from here before we can go much further using common language. Please make the effort, I'm begging you -- for your sake and the sake of your Guzzi!

 

If you make the typical mistake of chasing low vs. high speed compression damping (already opened here above, far far prematurely) without getting the basics nailed down FIRST, you'll soon be off in the tall grass for an endless session of aimless, blind-leading-the-blind, whackin' and trackin' every single speculation and conjecture, all the way down into the infamous Swamp-o'-Confusion, where many a newborn Guzzi suspension setup goes to suffer abandonment, and neglectful, unsupervised infant mortality, my friend. :o I, for one, intend to play on the fairway. Your call. B)

 

post-1212-1209152619.jpg

Another tough lie on the very brink

of the Infamous Swamp-o'-Confusion

 

TTFN. Come back? ;)

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Renato,

 

Are forks/triple clamps/axle all aligned properly?

 

Could be too much oil, but like ratchet says, best to start at beginning with proper measurement of oil. As said - you won't necessarily have expelled all the old oil when you drained the tubes. Did you remove & dismantle forks when you did oil?

 

KB :sun:

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We could guess, speculate, and indulge in all manner of conjecture and miss the mark by a mile, or 2 miles, or 200 miles. :rolleyes:

 

That seems to be the norm with cyber diagnostics. I hope he read your first post and the following who agreed with you as it is the only way to approach this issue. Maybe he and others will proceed with dialing in the basics before the speculation here encompasses things like barometric pressure and the subtle differences in ride quality due to tire compound and profile. :whistle:

 

For many, it seems that doing any amount of "homework" is well, punitive -- and it's simply not worth the effort. :(

 

Well, one positive is, if you can read between the lines and sort through the litter, this forum will do a lot of homework for you. It has for me. :thumbsup:

 

And waddayagonna do? :huh2:

 

Keep typing and reading I guess.

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Ok,when i purchased her n i say her because she can be a *&%## sometimes but ya gotta love her, she rode great then it started getting stiff so i changed the oil with amsoil light fork oil, put in exactly what factory recomends (factory dealers man. dont ever buy one) and she rode perfect, i dont put much of a load on her since most of my riding was in nyc (pot holes the size of snake river canyon) i wieght about 180 pounds. anyhow then it started to ride hard again so i drained 1/4 oz and it made no difference. She does not bottom she just wont move much and at a stand still she only moves about 3 inches with all my wieght being forced down and recently the bushings are starting to go probabally due to the front end not working properly, or could that be due to hard braking, you do have to compete with cabs and buses in the city, hope this is enough, thank you.

 

This sounds like some sort of seizing, what with the gradual buildup of stiffness until they don't budge.

 

Time for new seals?

 

As others have pointed out, it's virtually impossible to get all the old oil out of the forks w/o complete disassembly, and the factory spec for oil "to fill" is for dry empties. So you may simply have too much oil, like has been suggested.

 

Definitely read the links Ratch' provided, they're chock full of content; good to know even if you don't have any suspension problems! :thumbsup:

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If you changed the fork oil and the forks worked "perfect" afterwards and then over time went down hill, I would venture a guess that it is/was not an oil level issue. It would sound to me like a mechanical issue. The forks may be binding due to the tubes being twisted in the clamps(easy to fix) or the bushings may be worn out(harder to fix). If the bushing have too much clearence, the forks will not work right. Don't confuse the bushings with the seals. When the seals go the fork leaks oil. When the bushings go the fork will have play in the fit between the tubes( which will typically cause the seals to go and then the fork will leak oil).Adding or subtracting oil is unlikely to make a difference if the forks worked well and then did not without a change in the oil level to begin with.

If the bushings are worn out, I would pull the forks and have a pro re-build them. Replacing bushings in a fork is one of the few jobs on a bike I will not do. If the seals are leaking, they are not to hard to do but many would still take it to a pro. I would change them myself but I hate paying people for something I could have done myself.

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Renato, many here (including myself, I b'lieve) can help you. Knowing your weight is at least something to start with, but you've got a ways to go in providing pertinent information.

 

From your response, it appears that you didn't as much as look at the suspension setup links I provided above. If we're gonna get any further here my friend, you're gonna hafta break down and do that, otherwise we'll very soon be bogged down in pages of unproductive thrashing, and frankly, I'm gonna lose interest real quick -- though you'll no doubt continue to get lots of potentially misleading speculation and conjecture without end here, most of which will confuse you past the limit of both your patience and mine. . . . <_>

 

If you put in the factory recommended volume of fork oil without getting all the old oil out (very typical), you more than likely had it overfilled and/or mismatched right and left, which would potentially cause severe air spring effects at the bottom of fork travel and/or binding of the fork. If you look at the third link I provided above, the principle at work is explained very simply. The ONLY correct way to set air gap is to measure it directly from the top of the stanchions, as described -- and IGNORE the factory spec'd volume altogether.

 

The list of speculation, which very quickly begins shooting off in all directions without a proper footing, has already well begun. Believe me, it goes on forever -- just trust me on that one at least? <_ so we already need to back up the old speculation train get on right track with something far more basic which is what i asked you start that being if installed springs correctly matched your riding weight and adjusted sags please understand continue ignore this no one here or anywhere else can help make assumptions without risk of going off countless rabbit trails nowhere. don have slightest idea dealing in terms spring rates sag settings preload etc. any discussion about operation damping opposed dampening src="%7B___base_url___%7D/uploads/emoticons/default_wink.png" alt=";)"> ) will be of no value to you, and will have you confused, pissed off, and completely lost -- and very quickly, at that. :huh: Again -- The basics of fork setup are described in simple, straightforward language in the first two links I provided above.

 

We're getting somewhere, my friend, but not nearly as far -- or as quickly -- as we could be if you had a grasp of the basics. You've simply got to get ahold of the basic concepts to communicate what you're starting with and where you think you want to go from here before we can go much further using the same language. Please make the effort, I'm begging you -- for your sake and the sake of your Guzzi!

 

If you make the typical mistake of chasing high vs. low speed compression damping (already opened here above, far far prematurely) without getting the basics nailed down FIRST, you'll soon be off in the tall grass for an endless session of aimless, blind-leading-the-blind, whackin' and trackin' every single speculation and conjecture, all the way into the infamous Swamp-o'-Confusion, where many a newborn Guzzi suspension setup goes to suffer abandonment, and neglectful, unsupervised infant mortality, my friend. :o I, for one, intend to play on the fairway. Your call. B)

 

tough_lie.jpg

Another tough lie

 

TTFN. Come back? ;)

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Renato,

 

Are forks/triple clamps/axle all aligned properly?

 

Could be too much oil, but like ratchet says, best to start at beginning with proper measurement of oil. As said - you won't necessarily have expelled all the old oil when you drained the tubes. Did you remove & dismantle forks when you did oil?

 

KB :sun:

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