Increased pull when letting off on the throttle.

[DaielHancock]

Hi, i have a 2004 suzuki gs500e, k4 model. I have notice that my bike takes alot longer to go through the 3-6k rev range than any other range. Is this usal in Gs500's?

Also i have noticed that the bike gets a surge of power when i start to bring the twist grip back to the closed position, this only happens after i have had it at full throttle and then start to return it to the closed position, it surges when i only return a very slight amount and then stops as i keep closing the throttle.

I was wondering whether this was a symptom of being to rich?, Im not quite sure. i know a little about carburettors as i had to take them off the gs to change the jets around as the previous owner mixed up the main and mid jets. during this swop around i also noticed i was missing a spring on one of the needles, i put in a new spring and returned the clips to the 2nd notch i believe. Could it be something to do with the needle position,  did i put it on the wrong notch? also the carb was missing a mixture skrew, so i bought a new one but i think its still missing an o ring.

Any ideas would be much appreciated.

[tb0lt]

Couldn't help but notice how you said the throttle has to be brought back to the closed position. Does your throttle not close by itself the moment you let go?

[skirecs]

i think your main jet is too big, i had similar symptoms of increased power at maybe 75-80% over 100%

[The Buddha]

Hi, i have a 2004 suzuki gs500e, k4 model. I have notice that my bike takes alot longer to go through the 3-6k rev range than any other range. Is this usal in Gs500's?

Also i have noticed that the bike gets a surge of power when i start to bring the twist grip back to the closed position, this only happens after i have had it at full throttle and then start to return it to the closed position, it surges when i only return a very slight amount and then stops as i keep closing the throttle.

I was wondering whether this was a symptom of being to rich?, Im not quite sure. i know a little about carburettors as i had to take them off the gs to change the jets around as the previous owner mixed up the main and mid jets. during this swop around i also noticed i was missing a spring on one of the needles, i put in a new spring and returned the clips to the 2nd notch i believe. Could it be something to do with the needle position,  did i put it on the wrong notch? also the carb was missing a mixture skrew, so i bought a new one but i think its still missing an o ring.

Any ideas would be much appreciated.

I have come across this in 1 bike I worked on. It also had a DJ kit in it, I could not figure it out and I didn't work on it enough to try everything so I dont know. Also I have worked on several other bikes with DJ's in it and dont have this problem.

So we should go back to basics on it.

Do a 4-5K plug pull. You know how to do that ? get to an empty road with a good shoulder, get the bike going in 3rd or 4th, hold steady throttle so it stays 4-5K for 5 seconds, then holding the throttle there hit the engine kill switch, pull the clutch in and pull off the road. Then wait 3-5 mins. Then pull the plugs and check and be very careful, they will be hot.

Also how does it behave @ steady throttle in the 3-6K range.
And how is the startup and warmup times. Need choke ? no ? for how long does it need choke ...

I too suspect it is being rich but have to pin point it further.

Cool.
Buddha.

[DaielHancock]

Couldn't help but notice how you said the throttle has to be brought back to the closed position. Does your throttle not close by itself the moment you let go?

Sorry it does return by itself. i just mean when i ease off a little.

[DaielHancock]

i think your main jet is too big, i had similar symptoms of increased power at maybe 75-80% over 100%

and yes thats probably a better way to put it, i get more power at about 80% throttle than at full.

[DaielHancock]

Hi, i have a 2004 suzuki gs500e, k4 model. I have notice that my bike takes alot longer to go through the 3-6k rev range than any other range. Is this usal in Gs500's?

Also i have noticed that the bike gets a surge of power when i start to bring the twist grip back to the closed position, this only happens after i have had it at full throttle and then start to return it to the closed position, it surges when i only return a very slight amount and then stops as i keep closing the throttle.

I was wondering whether this was a symptom of being to rich?, Im not quite sure. i know a little about carburettors as i had to take them off the gs to change the jets around as the previous owner mixed up the main and mid jets. during this swop around i also noticed i was missing a spring on one of the needles, i put in a new spring and returned the clips to the 2nd notch i believe. Could it be something to do with the needle position,  did i put it on the wrong notch? also the carb was missing a mixture skrew, so i bought a new one but i think its still missing an o ring.

Any ideas would be much appreciated.

I have come across this in 1 bike I worked on. It also had a DJ kit in it, I could not figure it out and I didn't work on it enough to try everything so I dont know. Also I have worked on several other bikes with DJ's in it and dont have this problem.

So we should go back to basics on it.

Do a 4-5K plug pull. You know how to do that ? get to an empty road with a good shoulder, get the bike going in 3rd or 4th, hold steady throttle so it stays 4-5K for 5 seconds, then holding the throttle there hit the engine kill switch, pull the clutch in and pull off the road. Then wait 3-5 mins. Then pull the plugs and check and be very careful, they will be hot.

Also how does it behave @ steady throttle in the 3-6K range.
And how is the startup and warmup times. Need choke ? no ? for how long does it need choke ...

I too suspect it is being rich but have to pin point it further.

Cool.
Buddha.

sorry what do you mean by DJ's? is that upgraded jets? I remember reading the numbers off the jets when i had the carbs apart, they read the standard for the k4 model. so i dont think they are larger.

Plug pulls,  i have read about doing those before, but i wouldnt really know what i was looking at when i took the plug out, can you give me some idea on what to look for?. also do i need new plugs before i do it?

i would say the bike is steady at 3-6k but sometimes you can feel a slight increase and decrease in power even when the throttle is held steady.

the bike starts up without choke but will almost die/ idle very low if you dont give it a bit of throttle. it starts and idles at about 4k with the choke fully on and i would say a 5 minute ride, maybe not even that, and it will idle without choke at the normal 1200rpm.

[mister]

this only happens after i have had it at full throttle

In the 40,000 clicks I've put on my GS, I don't remember every going WOT/Full Throttle (that is, turning the throttle all the way until it stops and holding it there).

What kind of riding are you doing that requires you to do this?

Michael

[Cosimo_Zaretti]

My first thought is fuel starvation with the throttle open, so that the power actually increases as you close the throttle because it was leaning out.  I'm not an expert in motorcycle carbs, but I have experienced that very unsettling surge as you lift off when I've had blocked fuel filters in cars. 

[tt_four]

Plug pulls,  i have read about doing those before, but i wouldnt really know what i was looking at when i took the plug out, can you give me some idea on what to look for?. also do i need new plugs before i do it?

I know, they all look the same, right?

[viggen]

this only happens after i have had it at full throttle

In the 40,000 clicks I've put on my GS, I don't remember every going WOT/Full Throttle (that is, turning the throttle all the way until it stops and holding it there).

What kind of riding are you doing that requires you to do this?

Michael

I spend a lot of time on a 50 mph highway commuting.  My experience has shown that I prefer WOT when a car decides suddenly that sharing my lane would be nice   Could be what he's facing, too.  Anyways, my '04 does the same thing with stock jets, making wot less useful..  Gs wiki implies this may be a lean condition.  My plan is to install the fatter jets from Buddha when I get around to it.  Have a great weekend fellas!

[The Buddha]

sorry what do you mean by DJ's? is that upgraded jets? I remember reading the numbers off the jets when i had the carbs apart, they read the standard for the k4 model. so i dont think they are larger.

DJ is dynojet kit. If you have a needle with adjustable grooves that = dj.

Plug pulls,  i have read about doing those before, but i wouldnt really know what i was looking at when i took the plug out, can you give me some idea on what to look for?. also do i need new plugs before i do it?

Old plugs read better, new plugs clean off too well to get you a good read. You are looking for the color on the hook and the point electrodes.

i would say the bike is steady at 3-6k but sometimes you can feel a slight increase and decrease in power even when the throttle is held steady.

That is a lean surge - You're lean in the 3-6K range.

the bike starts up without choke but will almost die/ idle very low if you dont give it a bit of throttle. it starts and idles at about 4k with the choke fully on and i would say a 5 minute ride, maybe not even that, and it will idle without choke at the normal 1200rpm.

That sounds like a normal good jetting @ idle.

So you may just be lean @ 3-6K, what throttle position range is that ... 1/4-1/2 ? If so, I'll check the float level.
If you're a bit higher up, also lift the needle 1mm or so - 1 clip position. You may have other stuff going on, this was 1 problem that I never managed to figure out ... so you're adding to the gstwin knowledge base. Test it and post please.
Cool.
Buddha.