GS500F sputter issue?

[油井緋色]

I don't know if sputtering would be the right word but here's the description.

Slight loss of power on higher RPMs (I don't know if this is true or not, it's just my "gut" feeling).
Sometimes rolling the throttle on neutral will do nothing. With friends, sometimes I rev like a race wannabe at red lights (don't judge!) but do not ever launch or redline the bike, this 'revving' sometimes produces no noise at all. It has happened a few times, though very rarely, when I'm actually riding and twist the throttle completely.

My bike is approaching 24,000. I've only done the following on it:

change air filter, front tire, rear tire
change oil (multiple times)

Rosey Toes told me not to worry unless something weird happens...well, this is something weird. What could it be? Valve adjustment? (No I haven't done it).

 

[RockerGuy]

You need to elaborate on "rolling on the throttle will do nothing"

Maybe check the fuel filter?

Did u do anything to the bike prior to this happening?

 

[油井緋色]

You need to elaborate on "rolling on the throttle will do nothing"

Maybe check the fuel filter?

Did u do anything to the bike prior to this happening?

There's a fuel filter? lol

This happened shortly after I changed the air filter at Rosey Toes, it was just a normal filter that you slip in =/

Best way to describe rolling on throttle will do nothing is literally what it means. Very rarely, usually when the bike isn't completely warmed up, rolling on the throttle in a quick burst will result in no rise in RPM or engine noise, my gf also said she saw black smoke come out of my exhaust once, I've never seen that before though.

 

[RockerGuy]

You're right, u don't have a fuel filter, my bad.

Maybe the installation was not properly put together. Make sure the vacuum hoses are all connected properly

 

[油井緋色]

You're right, u don't have a fuel filter, my bad.

Maybe the installation was not properly put together. Make sure the vacuum hoses are all connected properly

lol I wasn't implying I didn't, I actually didn't know if I do or not.

I'll check later in the day, hopefully it isn't something like rejetting or valve adjustment as I have no idea how to do those or what they even do, but I know some sites said changing the air filter may require rejetting, and my manual said I needed a valve adjustment at 16,000, which Ted said I didn't need.

 

[tricky]

did you replace the air filter with a stock one? or did you switch it to some high flow filter? Anything but stock would definitely require a rejet, they run very lean from the factory already

Typical Lean Conditions:
- Poor acceleration; the engine feels flat.
- The engine won't respond when the throttle is snapped open, but it picks up speed as the throttle is closed. (A too-large main jet also mimics this symptom.)
- The engine runs hot, knocks, pings and overheats.
- The engine surges or hunts when cruising at part-throttle.
- Popping or spitting through the carb occurs when the throttle is opened. Or popping and spitting occurs through the pipe on deceleration with a closed throttle.
- The engine runs better in warm weather, worse in cool.
- Performance gets worse when the air filter is removed.
Typical Rich Conditions
- Engine acceleration is flat and uneven and loses that "crisp" feel.
- The engine "eight-strokes" as it loads up and skips combustion cycles.
- The engine's idle is rough or lumpy, and the engine won't return to idle without "blipping" the throttle.
- The throttle needs to be open continuously to maintain acceleration.
- Black, sooty plugs, a sooty exhaust pipe and black smoke from the tailpipe that stinks of unburned fuel.
- Poor fuel economy.
- The engine works better when cold. Performance falls off as it warms up or the ambient temperature rises.
- Engine performance improves when the air cleaner is removed.

 

[油井緋色]

You are right, I got an aftermarket filter. Old one was stock, can I just order a stock one instead of rejetting to save $? lol

EDIT: Son of a *****! New filter is 40 bucks, rejet is 200 bucks at Rosey Toes. I have NO CLUE how to do a rejet and after googling definitely do not want to do it myself =(

I'll pay someone if they wanna come over to help!

EDIT EDIT: After more googling, looks like I need to reject regardless. =(

 

[llaen]

Hm, I'm not an expert, but shouldn't they have warned you about this before changing the filter?

 

[rdwarior]

If you replace your new aftermarket filter with a stock one, there is no need to re-jet.

 

[油井緋色]

Hm, I'm not an expert, but shouldn't they have warned you about this before changing the filter?

The guy that did it was pretty newbie -_- It wasn't Ted or Kevin, was a new guy...he even needed me to help him with it lol

And @ rdwarior, that's what I thought but...
http://cgi.stanford.edu/~sanjayd/gs500/Upgrades/AirFilter
Changing from stock to stock requires a rejet, apparently so does the hiflo even tho it says you don't. What are the implications if I choose not to rejet for a bit (3000km).

 

[Sabex]

The guy that did it was pretty newbie -_- It wasn't Ted or Kevin, was a new guy...he even needed me to help him with it lol

And @ rdwarior, that's what I thought but...
http://cgi.stanford.edu/~sanjayd/gs500/Upgrades/AirFilter
Changing from stock to stock requires a rejet, apparently so does the hiflo even tho it says you don't. What are the implications if I choose not to rejet for a bit (3000km).

The bikes come lean from the factory. Increasing the airflow will just make it run even more lean. It depends on how lean the bike is running. If it's too lean, I wouldn't ride it very long.
And why did you change the air filter? Did you try just cleaning it first?

It would also be beneficial to pull the carbs and clean them. Then rejet + reassemble. Although you could do it yourself, and save lots of money.

The website also says a rejet is RECOMMENDED. Simple because the bike comes from the factory lean. it has nothing to do with the fact that it's a stock air filter being put in; just how suzuki made the bike.

GStwin recommends that all stock gs500f's be rejet. It will improve performance and engine life.



If you run a bike too lean for too long, you can damage it pretty bad. Running lean causes the engine to run a lot hotter than normal, all kinds of things that can be burned.

 

[油井緋色]

Son of a *****. Well, guess I better get this done asap before I blow **** up. And frankly I do not trust myself at all to do this. I'd rather pay the $200 bucks and have a 99% chance of success rate than pay nothing, **** something up, and end up with a giant headache and maybe more than $200 that i have to spend.

And I changed it because I'm an idiot and the owners manual said to change it 12,000km ago. Did not realize it needed rejetting after.

 

[llaen]

Son of a *****. Well, guess I better get this done asap before I blow **** up. And frankly I do not trust myself at all to do this. I'd rather pay the $200 bucks and have a 99% chance of success rate than pay nothing, **** something up, and end up with a giant headache and maybe more than $200 that i have to spend.

And I changed it because I'm an idiot and the owners manual said to change it 12,000km ago. Did not realize it needed rejetting after.

Seems to me you can just replace the new filter with stock and not worry about it unless your problems persist.
Do you still have the original part or did they throw it out? It's a waste of money to get another new filter, but better than spending $200.
You can even point out to the mechanic that you got screwed over with the aftermarket air filter and request a partial refund or something, but that's up to you.

As Sabex pointed out, the rejetting is recommended for all gs500s in general. It doesn't mean that you have to do it right now.
If you're sticking with this bike in the long run, get comfortable with it, do some simple maintenance on it and build up your confidence. You may end up rejetting it yourself in 1 or 2 years. Lots of step by step guides out there. If you can use someone's garage (like your parents), that's even better.

Anyway, good luck!

 

[Sabex]

Son of a *****. Well, guess I better get this done asap before I blow **** up. And frankly I do not trust myself at all to do this. I'd rather pay the $200 bucks and have a 99% chance of success rate than pay nothing, **** something up, and end up with a giant headache and maybe more than $200 that i have to spend.

And I changed it because I'm an idiot and the owners manual said to change it 12,000km ago. Did not realize it needed rejetting after.

How much did you pay to change the air filter btw? It's the easiest damn thing if you're using a drop-in. You just take off the tank, unscrew some screws, and you're good.

One more thing about rejetting: it's not just taking it apart. it's trial and error to try and find EXACTLY what works for your bikes setup (as tricky said in your thread in general) http://beergarage.com/GSMatrix.aspx here is a matrix of some users over at GSTwin (tricky mentioned in other thread), and their bike setup + jets, and a comment on what it's like. It's a good base for figuring out roughly what you need. But it's still trial and error. Rejet, try it out, rejet again until it's perfect.

it helps to read up on carburators also, to know exactly what jet does what and when.


Considering you don't trust yourself (and given your previous history of bike maintenance), I would suggest bringing it to a mechanic, carburators are one of the things that if you **** it up, it's ****ed up big time. (They're also expensive)
I would also suggest asking if you can watch them do it, and tell you what they're doing. Maybe it'll help you learn a few things so you can do it yourself next time.

Of course, as llaen said; you don't NEED to rejet it right now if you swap back to the stock air filter.

 

[油井緋色]

The filter was like 40 bucks, I just find it odd that the wiki said no rejet required...and yes it is a drop in. I also changed my front tires that day, Ted charged me 30 bucks for labour when installing (where I had to help -_-). Again, next time I go to Rosey Toes, I'm gonna just wait for Ted or Kevin.