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Discussion Starter #1 (Edited)
Ive had my 04 gsx750f for a couple years now. Only had 6500miles when i bought it. Its my baby and it only get the best(fuel, oil, etc) Last night me and my girl went out for a ride. Well, i decide to lay its ears back!! And she pulled real strong till we hit 120mph. Then it was like there was nothing left! Is it time for a major tune up? Or is this the symptoms of a larger problem?
 

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Ive had my 04 gsx750f for a couple years now. Only had 6500miles when i bought it. Its my baby and it only get the best(fuel, oil, etc) Last night me and my girl went out for a ride. Well, i decide to lay its ears back!! And she pulled real strong till we hit 120mph. Then it was like there was nothing left! Is it time for a major tune up? Or is this the symptoms of a larger problem?

Yes it is a symptom of a larger problem, see ER's post!
 

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Discussion Starter #4
Is the rev limiter failing? Because even with the factory gearing at 120 i'm only in the 9-10 rpm range! Way shy of what the bike is rated at. I could see if I was close to the redline.
 

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its more of your probably hitting the max speed cap imposed by the rev limiter, on most liter+ race bikes thats 186mph ( even tho most are capable of much more) the gsxf has a lower limit than that and 125mph or so sounds about right for that bike. theres doodads you can attach that will override the max speed limiter. however 120mph on public roads is already license revocation range for most places.

ps i dont ever recommend 100+ with a passenger.
 

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Discussion Starter #6
I appreciate the heads up. But if i didnt already have a baseline performance for my bike I would give a nod and go on. But when i first got the bike i buried the speedo no prob past 160! So I know the bike is quite capable of doing what is says it would. And I have to give the thumbs up to suzuki! The bike is very stable at high speeds! So basically, the main question is; if it could do it before? Why not now? Ty slozomby any other input you might have on this matter is appreciated
 

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whens the last time you cleaned the carbs/air filter, and replaced the sprokets/chain & plugs. have you done any work on the bike recently?

i was thinking of the newer gsxf's (bandit style) , your 750 should top out around 160 indicated, or 150ish gps/speedohealer.
 

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Discussion Starter #8
Religiously! Every time i do an oil change. I just recently re-installed the factory rear sprocket for a little bit better fuel mileage. Had put on taller aftermarket on to bump my acceleration. Had it on for about a month, and decided to change back due to the fact I didn't like where the rpms were. Whoopie! i can pop a wheelie. Big deal my bikes not made for that. I'm a performance nut!!! And i like being able to squeeze all I can outta it. But not at the cost of grenading my bike. Donald trump I am not! lol
 

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I'm a performance nut!!!
So does that mean that you bump it off the redline often ??

Any other mods been done to the engine system ??

Could be a lot of things, or even a combinatin of things.

You aren't using "premium" fuel if the engine doesn't require it, are you ? (octane does NOT equal power).

Then there is loss of compression, valves warped or out of adjustment, restricted intake or exhaust, float levels off not putting enough gas in the bowls, etc.

I personally think that if it really DOES pull good up to 120 and runs good otherwise, you should not worry about it.
And once again, the slightest little glitch at 120 can and will KILL YOU.
 

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Discussion Starter #10
No, it doesnt redline till 12. And as far as fuel? I run the higher octane once in while just to keep things nice and clean. Only mods to the bike are a k&n filter kit and a yoshimura exhaust package(which came with the bike) The way I see it.. if it aint broke? Why fix it? Now, I did lay the bike down last year(thanks to friggin bambi!) But it was a low speed incident. And after going over the bike. Once I got it home...($400 to flatbed it from blue ridge prkwy to sevierville Tn.) Most of the damage appeared to be cosmetic.
 

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No, it doesnt redline till 12.
And as far as fuel? I run the higher octane once in while just to keep things nice and clean.
Only mods to the bike are a k&n filter kit and a yoshimura exhaust package(which came with the bike)
You missed the question: How often do you hit 12 when going up through the gears ??

Octane does not have more power and it does (generally) not clean any better either. You would be better off giving it a dose of B12 or Gumout every so often in the regular gas.

Given those mods, it is possible that the carbs weren't jetted, or not done right. It may be running lean.
How long since you changed the plugs ?? If they look stark white, you might want to put a stock air filter back on it.

Anyhow, 120 is more than enough for anybody. Think for a moment what would have happened if Bambi jumped out in front of you at that speed.
 

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Probably needs a valve adjustment and maybe a carb sync in it's not FI.
As for premium gas to clean things up...well that simply doesn't do a thing,regular actually burns hotter and quicker.
Premium's higher octane rating is actually so it wont burn so fast causing detonation (ping & knock) by exploding before spark occurs off compression heat like a diesel engine.
This is why higher compression engines need it,if you run good on regular gas higher octane fuels will do absoutely nothing but cost you more money.
 

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Discussion Starter #13
I never redline my bike. Under normal riding conditions very rarely does it ever go past 8k. I do zmax it once in a while. when I have the spare funds. I suppose if I dont put high octane in as much I might have more money for the additives! lol Thanx for the heads up on that. My scheduled tune up is right around the corner. So I'll have a better idea whats going on inside. Is there a better plug out there for my bike? I usually run bosh platinum and always had good results. Ya know? I guess I should start simple and check the fuel strainer and filter while I got the tank off.
 

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I do zmax it once in a while. when I have the spare funds.
What is Zmax ??

If the cost requires "spare funds", you are using the wrong thing.
A can of Berryman's B12 Chemtool costs about $3.75 and will do about 4 treatments.

In the many moons that I have worked on gas engines, I have never found a need to use anything but "standard" spark plugs.
Those usually can be had for about $3 apiece. Setting the proper gap is important.
 

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Discussion Starter #15
Wow! Never heard of it? Ok.. well its a tested additive primarily for your crankcases. But they do make a product for fuel as well. What it does is when the metal gets hot this stuff is actually absorbed. They call it micro something blah blah blah. But I guess the best way to describe it is like putting a film of teflon on all the moving parts to reduce friction and wear.



Btw, you ever heard a chain stretching in only one section? I was under the impression they stretched uniformly.
 

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Wow! Never heard of it? Ok.. well its a tested additive primarily for your crankcases. But they do make a product for fuel as well. What it does is when the metal gets hot this stuff is actually absorbed. They call it micro something blah blah blah. But I guess the best way to describe it is like putting a film of teflon on all the moving parts to reduce friction and wear.



Btw, you ever heard a chain stretching in only one section? I was under the impression they stretched uniformly.
You may have found your problem. Teflon is the last thing you want in an engine with a wet clutch, It usually causes a wet clutch to slip as the teflon is absorbed into the clutch material. The first symptom is slipping in the top gears. By the way most experienced consider oil additives snake oil, does more harm than good in a motorcycle engine.

Yes a chain will almost always wear uneven eventually. I suggest the best thing you could do would make friends of an experienced rider.
 

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You also might consider the bike being eight years old having wear...no matter how well you maintain it....a little here and a little there equates to a loss of horses...
 

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But I guess the best way to describe it is like putting a film of teflon on all the moving parts to reduce friction and wear.

Btw, you ever heard a chain stretching in only one section? I was under the impression they stretched uniformly.
YOU NEED TO STOP PUTTING CRAP INTO YOUR BIKE.

As was mentioned, that has no doubt damaged your clutch, probably beyond hope without a plate replacement.
Clutch slippage shows up first under the heaviest load; high speed in top gear.
If you haven't used any of it lately, maybe you lucked out.
The last time I used a PTFE oil supplement in a car engine......about 30 years ago......it damaged the valve guide seals and started eating oil.

As for the chain, parts fail in all kinds of different ways. Yes it is possible for only one link to wear abnormally.
Playing drag racer off the line and doing wheelies can cause things like that.

When it is necessary to change out a worn chain, it is usually also advisable to change the sprockets too.
 

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Ive had my 04 gsx750f for a couple years now. Only had 6500miles when i bought it. Its my baby and it only get the best(fuel, oil, etc) Last night me and my girl went out for a ride. Well, i decide to lay its ears back!! And she pulled real strong till we hit 120mph. Then it was like there was nothing left! Is it time for a major tune up? Or is this the symptoms of a larger problem?
It's your Flux Capacitor...you need to add banana peels for lubrication, and pray to God you hit 88mph. Seriously though, sometimes you can love a bike too much. Just give it the basics and it will love you back, I promise. I think you need a new clutch as well
 

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Discussion Starter #20 (Edited)
Well guys turns out it was none of that. Turns out that the fuel line had a kink in it. Prob from the last time I had the tank off. Replaced the entire fuel line with a longer piece for more flexibility.

Fyi guys. I'm not a stuntman! Evel Kneivel isnt my gradfather! lol And tires are too expensive to be doing burnouts!!
 
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