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Discussion Starter #1
need advice? after hearing multiple horror stories on gsxr's titanium valves dropping, would aftermarket valve spring retainers eliminate this problem?or is it suzuki's design that has the gremlin? any advice would be greatly appreciated

THANKS shane
 
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i would suspect that the use of the Ti valves has now added an unexpected top end rebuild into the maintenance schedule. either that or a bad batch of valves/weakness in the manufacturing of them.
 

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Discussion Starter #3
if i get another 15k on engine ill swap the valves out, but in the meantime somebody has got to know something why these problems are happening
 
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if i get another 15k on engine ill swap the valves out, but in the meantime somebody has got to know something why these problems are happening

i guess my answer didn't make sense to you. Ti valves will wear out quicker than steel. 4 stroke dirtbikes with Ti valves have a top end rebuild schedule because of this. manufacturers won't tell you this but some of the internals on modern day sportbikes wear out quickly such as guides, springs, pistons(954 i'm lookin at you) etc............. each model has it's quirks and there is no bulletproof bike. you can't have the performance of a gsxr 600 with the longevity of a car engine.
 

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Discussion Starter #5
it crystal clear now, i know suzuki uses them on their dirt bikes so i believe what your saying. i didnt know why it was happening, hey thanks for the advice any other gsx tips you know besides oil pick ups?
 

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On the newer lightweight 4 stroke dirtbikes the valves snap after a while from fatique. Which isn't very long. Replace then before they break is expensive but less expensive than the damage caused by one breaking.

Titanium valves usually run thinner valve stems that just snap. The upgrade is to replace the valves and the guides with stainless steel. At least that's the latest and greatest fix so far.
 

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While it's expected that the Ti valves will go with time in normal use this sounds more like there's something else at foot here. What sort of troubles are you hearing and at what mileage?
 

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Maybe someone here could help explain, for those of us that don't know but want to, what exactly does it mean when you "drop" a valve or "float" a valve, and would a "desmodromic" system fix this? I have a decent basic concept of the workings of an engine, and have actually even gotten down that far with my hands, but don't know exactly the ins and outs.
 

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DRopping a valve is when the spring breaks or the stem breaks and the head of the valve literally falls into the combustion chamber. This leads to rather nasty sounds as you can well imagine.

Floating a valve is when you rev the engine past the point where the valve springs can maintain the pressure against the cam. In other words it's like a skier jumping over a hill (the cam lobe) and getting airborne off the lip and touching down later downslope. In other words the valve end is left behind by the retreating back of the lobe so the valve is "floating". In modest cases of this you just loose a bit of power since the valve is delayed in it's closing. It's also hard on the valve stem since it means the spring accelerates the valve and it slams into the seat instead of being placed there at a reduced velocity by the cam. In an extreme case of float the upcoming piston catches up to the valve and hits it. This often bends or breaks the valve. If it just bends then it's not so bad but if it snaps off the head then you're back to a dropped valve due to float. More nasty noises.....

The desmodromic system was intended to do away with the valve float. It's a wonderfully complex idea that is only moderatley complex to manufacture. But there's other ways to do it. Float is brought on by large heavy valves that don't have large and heavy enough springs to control them and the thirst for power and thus higher RPM's. But another way to provide the area needed for heavy breathing is more smaller valves. Smaller valves are more easily controlled by standard springs and this is the method most commonly used. That's why we have 4 and 5 valve cylinder heads.

Float in modern inline 4's is pretty much eliminated by the multiple smaller valves and the general use of rev limiters. However you can still float an bend a valve if you downshift too soon or too many gears and don't realize what you've done and let out the clutch. The ensuing over revving well past the redline will easily allow float and that leads to the piston catching up to the valves and then there's nasty noises again. The rev limiter won't help you if you downshift too far and let out the clutch.

So now you know as much as I do....
 

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Discussion Starter #10
On the newer lightweight 4 stroke dirtbikes the valves snap after a while from fatique. Which isn't very long. Replace then before they break is expensive but less expensive than the damage caused by one breaking.

Titanium valves usually run thinner valve stems that just snap. The upgrade is to replace the valves and the guides with stainless steel. At least that's the latest and greatest fix so far.
+9800 so how long you recommend riding it hard for before doing the upgrade? also i was told to put in after market oil pick up as gsxr's starve for oil is this true?
 
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+9800 so how long you recommend riding it hard for before doing the upgrade? also i was told to put in after market oil pick up as gsxr's starve for oil is this true?


all bikes will starve of oil if wheelied for exxxxxxxxxxxtanded periods but they won't starve if left on 2 wheels under normal riding.
 

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Eh Muh Gawd Becky!!
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aside from Martigirls Gixxer, where are the "others" you speak of who have had valve troubles??
 

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Not me!!
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aside from Martigirls Gixxer, where are the "others" you speak of who have had valve troubles??
Good question. martigirl73 averaged 200 kilometers a day on that thing in the 4 months. I spent a little time searching Gixxer.com. Found no mention of this.
 

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AKA Martini-girl!!
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so far i only have heard about my bike doing it...and the Suzuki rep didn't mention it happening to any other new gixxers....
 

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Discussion Starter #15
well theres mine which went at 20k, martigirl at 24k, and a guy in sudbury went at 23k.maybe it was a bad batch, but still i dont want to foot the bill if it happens again!
 

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Damn that sucks...what displacement and years are we talking about?
 
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