Choking on Full Throttle!!!

[vlt06]

Hi Guys!

I have a 2006 GS500 with 48000 kms on the clock which I have had since new......

Recently I have noticed when opening up full throttle ( more noticeably in high gear) the power starts to flatten out and jerk the bike around (kind og the same as running out of fuel before switching to reserve). However, if I lighten the slightest (talking about 1 or 2mm off the throttle) then the bike gives a quick jerk and then delivers the power which I would expect from the full throttle.

Now I ride this to work every day and it pretty much sits on the Highway 98% of the time around the 100 to 140 km h mark so I need the full throttle alot for over taking etc... and it is really starting to piss me off!!!!!

What I have done so far is;

Changed Plugs
Changed Air Filter
Tried different types of unleaded fuel
Drained the carby bowel's

Is there anything else relatively easy to investigate before engaging a dealer to have a look at it 

Any help or advise would be greatly appreciated

Thanks Guy's!!! 

[smartroad]

Just a thought, but having taken my carbs off, are the valves stopping where they are meant to? I almost sounds like at full throttle they are being pulled all the way round and starting to close again.

Just a thought

[vlt06]

Yeah, I did think about that but that wouldn't explain the jerking as like it is nearly empty would it?

[smartroad]

Yeah, I did think about that but that wouldn't explain the jerking as like it is nearly empty would it?

Could it upset the air flow?

[vlt06]

Yeah could be......

Then that would take me to the question as to what would throw it out all of a sudden

Is there a governing screw or bar that can be adjusted to lower my full throttle limit

[ohgood]

Yeah could be......

Then that would take me to the question as to what would throw it out all of a sudden

Is there a governing screw or bar that can be adjusted to lower my full throttle limit

You have a little adjustment at the grip and on the carb. I don't know if it will go past WOT really.

[Kerry]

Recently I have noticed when opening up full throttle ( more noticeably in high gear) the power starts to flatten out and jerk the bike around (kind og the same as running out of fuel before switching to reserve). However, if I lighten the slightest (talking about 1 or 2mm off the throttle) then the bike gives a quick jerk and then delivers the power which I would expect from the full throttle.

I have had the same thing on my '96 and my '99.  (Can't remember about my '00 - I didn't have it very long.)  Worse than just not giving you full power ... it seems to drink extra fuel at the same time!  I have never come up with a final solution; just adjusted the throttle back to the highest point at which it still "pulls".

But hey - if anyone figures it out I'm all ears!    (Or is that "all hair"? )

[vlt06]

Recently I have noticed when opening up full throttle ( more noticeably in high gear) the power starts to flatten out and jerk the bike around (kind og the same as running out of fuel before switching to reserve). However, if I lighten the slightest (talking about 1 or 2mm off the throttle) then the bike gives a quick jerk and then delivers the power which I would expect from the full throttle.

I have had the same thing on my '96 and my '99.  (Can't remember about my '00 - I didn't have it very long.)  Worse than just not giving you full power ... it seems to drink extra fuel at the same time!  I have never come up with a final solution; just adjusted the throttle back to the highest point at which it still "pulls".

But hey - if anyone figures it out I'm all ears!    (Or is that "all hair"? )

Yeah, i think I will give that a go

Another way to describe it as if riding without the air filter in at all where the carbs are not getting their constant velocity that they require and just keeps jerking as though it is starving.

I will adjust the throttle to prevent getting to this level but I guess it is only a band aid solution and I hate not knowing what the cause is 

Cheers!

[vlt06]

Ok... Found the problem

What it was, was that air filter!!!!

At first I was going through every thing to replace just to see if anything made a difference. When I came to check my air filter, I saw it was quite dirty as it has been in there for around 45000kms. So I went to a local Suzuki dealer to get a new one. I then found not only was the problem still there, but it actually got a little worse

After a month of persevering with it, I though I would take it to the dealer where I bought the air filter from and get their thoughts on it. After an hour of on the road testing and on their dyno, they could see and feel the brake down of full throttle. They then went strait to the air filter and realised it was an incorrect filter supplied.

They swapped it out for the correct part (13780-01D00), chucked it back on the Dyno and what do you know.... Full and smooth power back

The dyno chart showed that it dropped approx 6hp with the incorrect air filter and is now back to it's usual 46hp @ 6500rpm.

The bottom line is that a dirty or incorrect air filter can really mess with it's performance!!!

Thanks for all your help and input and I hope this helps someone else in the future

Cheers!

[ohgood]

cool !

[ben2go]

46 hp!That's damn great for a GS even modded.

[cd]

its pretty easy to clean your air filter.

fill a bucket with gas

throw in your scummy filter

slosh it around

take it out and dry it off, put it in your bike, run your bike

presto, new air filter

cost, couple bucks for gas you can now run in your lawn mower

[vlt06]

46 hp!That's damn great for a GS even modded.

Is that great?

I thought the original factory specs were 51.3 hp @ 9500 rpm (38.3 kW)

[ben2go]

most gS struggle to make 40 hp

[vlt06]

most gS struggle to make 40 hp

Damn that Wikipedia!!!!!

[ben2go]

The US bikes are jetted really lean stock.Other countries have advanced ignitions and better jetting stock.

[backd00r]

hey vtl - you didn't take note of the part number of the dodgy filter did you?

I swapped mine the other day and noticed the part number of the new filter was 13780-01D05, where the old filter was 13780-01D00.  there's an extension of the opening that runs about three quarters of the way inside the box. I popped it in anyway - it fit straight in - but starting the bike the last couple of days has been a my mama.

just wondering if it was the same offending part.

bd.

[pbureau69]

just get a round K&N filter and slip it into the air box and never have to worry about cheapass crappy paper filter getting clogged ever again.. clean it every 10,000 Miles and your good to go without any rejectting.