Triumphrat

TiggerTwo

I'm a curious***** so I had to phone Triumph UK regarding this "mysterious" but seemingly harmless fork "knocking" sound on my '05.

Triumph, tech support told me, the "knocking" sound is caused by the movement of a shuttle valve; which was installed as an anti-diving mechanism.
Supposedly, fluid moves both way through the valve and as the shuttle valve closes it emits the sound.

To me, it sounds like it could have been avoided in the design but doesn't seem to cause a safety issue.
However, it appears to bother some folks when encountering 'silent policeman", pot-holes, etc.... Rapid corrugation's would probably accentuate the annoyance.

I wonder if this is similar to a type of "emulator-valve" made by a company called Race-Tech, and others, but I do not know how they work exactly. Not sure if an "emulator" would move though?

Walt

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TorqueyT

Hi TiggerTwo

did you get the impression this could be the case on older bikes as well (2000)?

Noticed a slight knocking sound the other day when parking up, holding the front brake and pushing hard down on the handlebars. At the bottom the the compression I would get the sound. Immediately thought oh sh*t head bearings, but you've now given me a spark of hope.....

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TiggerTwo

TT - No, I don't believe so, at least not exactly, because they said it was due to the addition of a "shuttle" valve (anti-dive mechanism), to the 2005+ Tiger's as a means to counter (perhaps further dampen) the dive characteristics as found on the previous model year's. For, as you know, Triumph has weened the Tiger away from it's original off-road personality. This "shuttle-valve" was to provide for a more controlled, paved road surface.

Have you used the support line available to the U.K.? Perhaps there's something similar in the previous models.

Unfortunately, the answer's I have always gotten were second hand, thus, rather on the vague side, from the engineering staff, as they pass on the, "filtered", answer's to the Customer Support Staff.

From my recollection ( I use to work hydraulic/pneumatics as a young man - 25 year's ago) a shuttle valve comes in different configurations. But, I believe the basic theory is similar to a check valve in that fluid is allowed to flow one-way. However, in a "load-control, application, like suspension a "cartridge-type", "multi-port", "shuttle valve", the fluid flow is bidirectional and consists of two cycles. Volume is proportionally higher in one direction, as the suspension extends and pressure is lower than on the compression cycle when the fluid is compressing though smaller "relief-ports, thus slowing or retarding the dive?

The individual design application would dictate the proportion of the high volume/lower pressure side, larger bored port size to the low volume/ higher pressure "relief-side", small "bleeder" ports. This is my swing on it anyway.

I am gathering that the sound is actually the "shuttling" or movement of the "cartridge-type", shuttle-valve when the forks' tube and cylinder are at the neutral (resting-poise) position. Then, I suppose, when a sharp vertical drop is encountered the cylinder drop's and "drags" the shuttle-valve away from it's neutral position and surface. I believe the support tech said it was then on the return stroke that the valve met up with it's neutral position's surface (top of the cylinder/bottom of tube???) and thus the "knock" or "clank" sound gets produced.

I don't "chase bubble's" anymore, but instead logic bits. So, my understanding and definition of the cartridge-type, shuttle-valve function, in a "load-control" application, is most likely faulty.

However, I am sure someone here, on the forum, has more knowledge of this than I and may be willing to correct me and make clearer the scenario.

A bit of "shuttle-valve" definition, from Parker

Walt



[ This message was edited by: TiggerTwo on 2006-06-14 17:40 ]

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tyrebyter

The Race-Tech Cartridge Emulator is a different animal. Installation requires drilling the existing emulsion tube in several places to render it useless, handing the damping function to the Emulator. That Emulator is no more (or less) than a shim stack valve assembly that sits between the top of the emulsion tube and the bottom of the spring. I accidentally bought the Cartridge Emulator Kit (my dealer plays me like a cheap violin) and installed it one evening along with some Wurth springs. Holy moly! Best $160 I ever spent (having passed on buying Microsoft stock in the late '80s).

TIGER1454

Hi, Triumph via my dealer have said that this knocking only effects 2006 models, and not the 2005 version. I have two mates with cast wheel 2005 models, none of which have any knocking. Something ain't right with these explanations, if indeed you have the the notorious knocking.

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TiggerTwo

TIGER1454-

I'm going to have the fluid replaced and see if it goes away. Sounds simplistic, but I wonder if some of the bikes have incorrect oil levels?

It would be interesting to take it apart and have a look-see.

Walt

[ This message was edited by: TiggerTwo on 2006-06-27 09:50 ]

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TIGER1454

Hello TT, sounds like a good idea to change the oil. let me know if it works please, cheers.

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TiggerTwo

My 12K is scheduled for the 11th of July. I will let you know.

Walt

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06TIGER

I have had my 06 Tiger back to the supplying dealer 3 times for this problem, they say this is normal and so does Triumph when I wrote to them. They say it is down to functioning of the valves in the forks. However i have riden an 04 Tiger and it did not appear to suffer from the problem. I think I will try another dealer. It is really bugging me :???: :???:

triumph900

FWIW - It's not a 2006 issue, it's a 2005 > issue (until the '07 is released!).

Changing fluid AND/OR springs won't help. I've done both.