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Re: Fork Stick-shun

friction.
the TiN coating on forklegs makes 'em more slippery. less apt to stick when compressing/rebounding.
 

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Discussion Starter #3
Re: Fork Stick-shun

friction.
the TiN coating on forklegs makes 'em more slippery. less apt to stick when compressing/rebounding.
maybe should have rephrased that....

what are some common causes (applications) of stick-shun... I don't have TiN coated forks. is it something that has to do with the weather or how I washed the bike or something else?
 
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Re: Fork Stick-shun

internal damper tubes can be a source of stichion also.....
 

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Re: Fork Stick-shun

You're fork oil could look like mud, a fork leg could be bent, your axle alignment could be off, triples twisted,.............
 

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Re: Fork Stiction

The word is spelled: stiction (in case anyone wanted to know)

Just take your whole bike over to Aftershocks and have them fix the suspension on both ends. Or did you figure out why it had such strong rebound damping at the rear?
 

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Re: Fork Stick-shun

Daffe, that's a great question. Note that the telescopic forks have two "bushes". An inner bush and an outer bush. The outer bushing is right behind the dust and oil seals and is at the bottom end of the outer fork tubes. The outer bush glides along the polished EXPOSED chrome coating that you can see, lubricated by the oil held in by the oil seal. The oil seal receives added protection by the dust seal.

Now, the "inner" bushing is at the top of the chromed inner tube. While sitting on the sidestand, this bushing is like 6 or 8 inches from the top of the fork tube. The inner bushing glides along the polished inside of the top fork tube, lubricated by fork oil that happens to be splashed up there.

Now, imagine a few thousand pouns of force acting on the front end when you use the brakes. You've got the mass of the bike pushing on the fork stem, which then transmits the load to the outer tubes and then the bushings (very little contact area!!) and then to the inner fork leg. When you really contemplate the current "state of the art" system, it seems archane when you consider that the design is little changed from when 100hp out of 1200cc was a Big Deal.

Race Tech tries to pimp their fork bushings as "ultra slick" and honestly, I can't say whether they are better or same as the stock ones. BUT I do know that when you replace the oil seals, you use the interference of the bushings to drive out the oil seal, which often ruins OEM bushings and less often ruins the R-T aftermarket bushings.

Oh, and while we're contemplating all that force on the front end, consider how little contact area the steering bearings have and THOSE are getting a lot of force, too.

Ultimately, there's "normal" stiction that you'd feel just after a fork rebuild and then there's not normal stiction that's probably due to fork oil getting old or the bushings getting worn. You DO change your fork oil every 2 years? :) :) (even I don't...)

:) Chris
 
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Re: Fork Stick-shun

My question is, what made you concerned about stiction in the first place? Did something change in the way the forks felt? As Chris so eloquently pointed out, all telescopic forks have an inherent amount of stiction. Over time that can increase due to bushing wear and/or oil contamination. What contaminates it? Debris in the form of the cheese that wears off the bushings, damper rods, springs and everything else inside the forks. Then there's ultimate stiction - bent forks that won't budge after a crash. As long as that's not your problem you can reduce your stiction by flushing out all the old fluid and particulate matter in the forks, disassembling and inspecting the bushings for wear (and replacing them if necessary) and refilling with new fork fluid.
 

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Re: Fork Stick-shun

My question is, what made you concerned about stiction in the first place? Did something change in the way the forks felt?
I was there when the subject came up. We went to a charity event where Gary Jaehne, the local suspension guru (see: http://store.motolit.com/sportheradri.html), was setting up the suspension for people who made a $20 charity donation. On Daffe's bike, there was almost an inch difference in where the front forks stopped when they were pushed down and allowed to rebound compared to lifted and allowed to compress. It was clear that the forks were not sliding smoothly. After spraying libricants on the fork legs and loosening the triple clamps to attempt to realign things, it was determined that Daffe's forks needed additional help. Shortly after that, it was also determined that the rebound on the rear was way too stiff and adjusting the screw on the shock did nothing at all to correct it.

I still stick by my recommendation to drop the bike off at Aftershocks and have them fix both ends.
 
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Re: Fork Stick-shun

Daffe just an opinion......but since I have replaced the stock suspension bits, I have never regretted it. You might want to weigh the cost of rebuilding or buying some better bits. Since it appears you will be doing something anyways.
 

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Re: Fork Stick-shun

I think Daffe's got some S4 legs on his bike, so they're not a bad starting spot...
 

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Re: Fork Stick-shun

I don't get into rear shocks much, but I do a fair amount of fork work & modification. I'd start by taking off the fork legs & running a dial indicator on each one. Tell us what you get & we'll go to step 2.
 

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Discussion Starter #15
Re: Fork Stick-shun

... might just take the whole thing into Aftershocks since both the rear and front suspension have to be checked. I will try doing this sometime in January, since it rains a lot here. I'm gonna forego working on the fuel tank until I get the suspension fixed.
 

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Discussion Starter #16
Re: Fork Stick-shun (but now includes) Rear Sachs

Update: took the bike into Aftershocks today. Here is the result:

1. Fork Stiction: result of the front wheel replaced inappropriately when the front tire was changed out. The bottom of the fork on the R side was not set correctly, which resulted in the forks being aligned skewed. They loosened the bolts on the R-fork leg at the bottom and pried the clamp around the axle with a screwdriver then re-set it. The fork moved more freely after that.

2. Sachs rear shock: pretty much crapped out - crappy set up since it's a sealed-system and with no real adjustments to speak of. As such, it was a pretty sh!tty addition when the Monster was created. It was interesting to note that the M900 shock is also a Sachs but was a higher quality one compared to the M750 (based on Aftershocks' experience with working on monsters). The M750 set up is generally much poorer than the M900. Still, I was told that *my* set up was the worst they've ever seen.

Conclusion: ended up buying an Ohlins rear shock with remote reservoir (No ride height adjuster). They're going to take the Ohlins apart and re-set it for my weight and riding style. Apparently, if you're less than about 130 lbs, you're not going to make much of a difference in terms of chassis set-up compared to if the bike had no rider on it. I think I need to gain about 25 lbs or so. Additionally, I'm getting the forks serviced (oil changed, springs checked, etc). I was told the forks were NOT bent.
 

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Re: Fork Stick-shun (but now includes) Rear Sachs

Well, not only a 750, but also a dark one. Drop one more notch on parts quality.

But looking at the bright side, your bike is going to kick some ass after the service!
 

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Discussion Starter #18
Re: Fork Stick-shun (but now includes) Rear Sachs

commendations to you for actually reading my diatribe!

yeah - can't wait to get all that work done (minus some $$$)
 

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Fork Stiction (but now includes) Rear Sachs

Great to hear that you're finally getting the suspension sorted and that Aftershocks didn't try to do more than you needed on the front end.

As for gaining weight, why don't you get married? I heard that the average male gains about 25 pounds after marriage. ;)
 

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Re: Fork Stick-shun (but now includes) Rear Sachs

Daffe, If you have the S4 forks like I think you do, likely some softer front springs would help a bunch...that and a revalve. If your fork behaves like mine, it hardly moves on cracked pavement (high speed small bumps).

Looking forward to your feedback on results, I'm sure you'll like the Ohlins.
 
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