Easy "running rich" fixes?

[evi1joe]

I'm at 4700 miles, and I just changed to a full exhaust and shimmed the needles (two washers each). HOWEVER, I've been noticing things like a gas odor and even some backfiring (though I am riding much more comfortably and harder) and getting 40mpg...not sure, but o think it was better before.

Will pulling the airbox lean it out?

Please don't make me pull a shim or do anything that requires taking it apart again.

Any ideas? Maybe add some air to the tires? j/k

How do I know if it's TOO rich? And how long before it starts hurting stuff? Can I do 600 miles before fixing it?

[alex.s]

adjusting needles alone isnt doing enough with a full exhaust, change jets. jetsrus.com

running rich isnt as bad as running lean. you can do heat damage running lean too long

its unfortunate but thats how it goes. try a bigger jet, if its worse try a smaller jet. if the bigger jet is better, try an even bigger jet.

[evi1joe]

Dang...had sure hoped i could pull the air box (THAT looks easy!). So how much is a cycle shop going to charge me for a jetting job? What's a fair price to pay? There's no way I'm doing it...too much work and too little time as it is. I should have named my old twin girls Chaos and Entropy!

Gonna pull the plugs Monday and look fir brown or whiteness...also change the oil and sniff for a gas smell.

[alex.s]

having it done professionally is expensive. you're looking at anywhere between 200 to 400 depending on quality (if a dyno is used, etc) people say removing the carbs is extremely easy with pod filters. sounds like you might want to drop the box and buy some jets and start trying different ones out

[Nemesis]

Man, I'm seriously thinking of doing a DIY for you guys with back firing issues and how to remove the airbox. Unfortunately for you, I'm too lazy.

If your bike is backfiring, you NEED to rejet. My bike does not backfire whatsoever.

The easiest...I mean EASIEST way to take off the carb/airbox is by removing your rear cowl fairings, the rear wheel, the battery tray, the cowl underneath the battery tray, then the right side cover on the airbox (3 screws to remove), that one bolt under the left side of the airbox, and then proceed to remove or rather pull the airbox out from the back.

It takes me 10 mins to remove the airbox. <--this is probably because I have race fairings but even with stock fairings it took me less than 30 mins to remove. Prolly cuz I've done it a gazillion times.

[evi1joe]

Doh. I guess I could do 200-300... Though I like that the needles can be changed without removing anything nut the fairing, I just DON'T THINK I have the know how to tell if the jet I put in helped any or if I needed to go bigger/smaller....I'm not experienced enough to butt-gauge whether it's running too rich or lean. If it wasn't for the gas smell, I never would have noticed anything and assumed 40mpg was just the exhaust and my newly developing heavy handed throttling.

[evi1joe]

@Nemesis: it's only backfired once or twice during big downshifting, and twomor three times when I was gunning it. Wouldn't pulling my airbox make it run richer?

That's the only mod I know I can do fast.

[Nemesis]

Originally Posted by evi1joe

@Nemesis: it's only backfired once or twice during big downshifting, and twomor three times when I was gunning it. Wouldn't pulling my airbox make it run richer?

That's the only mod I know I can do fast.

Sorry for the confusion...my post wasn't to imply taking out the airbox completely. It was just to suggest there's an easier way to get to the carbs if you plan on keeping the airbox.

Have you played around with the mixture screws?

[k-os]

Originally Posted by evi1joe

@Nemesis: it's only backfired once or twice during big downshifting, and twomor three times when I was gunning it. Wouldn't pulling my airbox make it run richer?

That's the only mod I know I can do fast.

Replacing your airbox with pod filters will make it run leaner as it will be getting MORE air.

[alex.s]

its easy. just try different settings and write down what you thought. if theres a rev range where it struggles or if its good. you can tell the difference when its good and when its bad. they say to start rich and go lean until it starts giving trouble IIRC. then tune the fuel mix and idle jets. spend that 200$ on yourself and do your own labor. youll end up knowing more about your bike. you wont be sorry with the end result.

[DaBlue1]

Originally Posted by evi1joe

... I just changed to a full exhaust and shimmed the needles (two washers each). HOWEVER, I've been noticing things like a gas odor and even some backfiring (though I am riding much more comfortably and harder) and getting 40mpg...not sure, but o think it was better before.

Have you removed the snorkel and done the clean air removal? Also try not going from WOT to completely shut. That will also help with the occasional backfire. Until you decide to rejet you will still be OK with shims and the airbox.
Have you done any sprocket changes to help lower your rpms at all. That may help your MPG a little, but riding hard all the time will net you crappy mileage regardless.

[evi1joe]

Crap. I meant SNORKEL! Not air box.
Would pulling the snorkel help leant out a bit?!?
I CAN pull the snorkel for sure.

I also didn't plug any of the keen air stuff...maybe I need to plug those thing in that DIY.

[DaBlue1]

Originally Posted by evi1joe

Crap. I meant SNORKEL! Not air box.
Would pulling the snorkel help leant out a bit?!?
I CAN pull the snorkel for sure.

I also didn't plug any of the keen air stuff...maybe I need to plug those thing in that DIY.

Do all that and you should be straight.

[alex.s]

if i remember right needle height and fuel mix settings dont effect WOT fuel amounts... thats 100% controlled by your main jet. both full exhausts and pod filters / smoother intakes increase air flow through the engine, meaning you need to add more fuel to the mix in either case. you have to rejet.

[evi1joe]

My plan:

Pull the snorkel. (so this WILL help lean it out? Also, is it just me or was there a thin sealant tape like thingy around the snorkel?)

IF I still smell gas or have symptoms, plug sensors and do the keen air box mod.

IF all else fails, rejet.

[DaBlue1]

Originally Posted by evi1joe

My plan:

Pull the snorkel. (so this WILL help lean it out? Also, is it just me or was there a thin sealant tape like thingy around the snorkel?)

IF I still smell gas or have symptoms, plug sensors and do the keen air box mod.

IF all else fails, rejet.

Yes, pulling the snorkel will add more air and lean it out a little. The sealant around the snorkel is crap and will break easily enough. Doing the keeln air mod will help the occasional backfire. Also if you have a baffle for your exhaust, experiment with it to see what performs the best for you. You may find it better with it in. You should be able to pull the snorkel and test right away. If you are still not satisfied or like you said, all else fails rejet.

[evi1joe]

No baffle. So is the rich mixture not causing the few backfires?
THANKS EVERYONE!
This as been on my mind all week, but I just got to the forums today.

ETA: would an aftermarket K&N filter help lean it? I'd prefer not to have to maintain it with oil and stuff...I'd just rather replace filters.

[alex.s]

ok this is the last time i try to explain this, if you havent changed your jets and you put on a full exhaust, its running lean. going with a higher flow intake is going to make it even more lean. you NEED to rejet.

[setasai]

Couple things. A stock is running lean. Two shims under the needles gets mid to low at a good spot and high rich. Adding a full exhaust would lean out across high/mid/lows. Hence I think adding a 3rd washer would make it just a bit too rich and then pulling the snorkel would lean it out but might not be enough. Many riders with a full exhaust have had to go up to 3 shims plus pod filters.

With a full exhaust, the kleen air removal tends to help with the backfire. Either way, remove the snorkel and see how it runs but I suspect that if it still seems to run poorly, add pod filters and add a shim have been widely known to get pretty close.

As for the K&N filter.. you would still need to clean and reoil it. It's not that hard to do. If you want to replace instead of reuse, just get the OEM filter. It comes preoiled and is only like $10 if I remember correctly.

[evi1joe]

Good stuff. I'll try the snorkel, but after my IRS refund, jetting is in the works.
I'm still saving for the driving school needed to get my license. Hope to do that by mid-January.

[DaBlue1]

Originally Posted by evi1joe

No baffle. So is the rich mixture not causing the few backfires?
THANKS EVERYONE!
This as been on my mind all week, but I just got to the forums today.

ETA: would an aftermarket K&N filter help lean it? I'd prefer not to have to maintain it with oil and stuff...I'd just rather replace filters.

Your full exhaust is wide open where as the stock exhaust system has two so called catalytic converters along with a baffled muffler that helps reduce the sound of any backfire. BELIEVE IT OR NOT under the right conditions, backfire can even be heard from the stock exhaust can. To be honest you are not running all that rich, basically you just have a hollow system. Hollow systems equal noise.

Using an aftermarket drop in type filter in the airbox like a K&N, BMC, JFC, UNI or Pipercross will flow a little more air but nowhere close to using a pod type filter. Any air filter you use will require some maintenance, whether it is oil or a dirt retention additive, it will eventually have to be cleaned. However if you don't mind spending the money, simply replacing the stock filter is suitable. Because of the rubber frames around the K&K, BMC & JFC filters, cleaning is not as simpleas cleaning the stock filter. UNI and Pipercross make a filter the uses the existing frame off of the stock filter so replacement and cleaning is a snap as well.

[choneofakind]

OP, the stock bike runs lean in the midrange and idle circuits to save gas, and it's balls rich at the top end (that's the main jets) to ensure that the bike doesn't run lean and overheat the valves.

Going with full exhaust and snorkel removal will lean the whole range a little. This means that the top end will be closer to right, and the mid/low ranges will be more lean. Make sure that the main jets are not too lean first. Get one size larger (Keihin 100) than stock (Keihin 98) and go with the jet that works best. After that, worry about the needle height and then the idle circuits. If all you do is remove the snorkel and add a full system, you'll likely be alright to only test one size larger jet than stock, whereas if you were to go with a K&N R-0990 filter and remove the airbox, you would need to test a whole range of main jet sizes and pick the one that works the best.

The Jetting Database is a good place to get a feel for what others have used so you can start where someone with a similar setup and elevation as you; modify your carb setup from there to get your bike running right.

Jetting is 100% specific to each bike, so only change one variable at a time so that you can get your jetting right. The tuning guidelines from Factory Pro are helpful for getting it right.

Running a little rich is definitely preferable to running a little lean.

Another good idea is to make all your changes to your jetting according to the "butt dyno", and then take the bike to the shop to get a dyno base run to see what your AFR is at different RPM's so that you can see where you're running rich or lean and adjust accordingly. Ideally you should do a base run stock, and then another run after every change you make, but that gets expensive.

[cuong-nutz]

I think purchasing/renting a wide band 02 will help a ton with tuning. I believe a member is offering the rent/loaner wide band 02 with guage with a deposit.