Author Topic: my 4... carb problems??? bad gas milage, sputtering....... (Read 6348 times)

ridemoto4life · « **on:** February 03, 2006, 09:05:32 PM »

ok so ive read some of the posts for bad gas milage but im still going to post. so yes i am getting bad gas on my 97 1200 with a remus can and the last owner said he put a jet kit on there but im not sure. so ya other then the bad gas milage my bike is idling at 1600-1800rpm after getting off the freeway and between 5500-6000rpm my bike kinda sputters when i give it gas but it will cruise at that rpm and runs great under and over those rpms and when i first start it up when its cold it makes little poping sounds and when i first take off when its cold and sometimes when its warm starting out it pops.

rider123 · « **Reply #1 on:** February 06, 2006, 02:30:32 PM »

It means you're probably a little lean at least down low and mid range. Are the mixture screws drilled out? Try turning them out maybe 1/8th to 1/4 of a turn and see if it gets better. I'd be wary of what "jet kit" he put in there if at all. It may be all screwed up in there with some rpm levels horribly rich(bad gas milage) and others too lean(backfiring). You might want to bite the bullet and put a Holeshot or Ivan's in there to fix it and make sure 100% that its done right these bikes are pretty particular of what kits get put in them.

ridemoto4life · « **Reply #2 on:** February 08, 2006, 01:35:11 AM »

the guy at the suzuki shop said the same thing. the bike pulls alot harder down low when the bike is cold so it must be lean. the guy sent me this e-mail when we were writing back and forth about the bike.

"I remember my mech said it has 155 main jets and 45 pilot jets
but look at the mixture screws especially the mixture screws are inset
somewhere, the were originally plugged and had to be drilled out for
adjustability. The only deal is the carbs wont be synched anymore if you
adjust them. To synch them there is some sort of 4 dial vacuum gauage
thing to set the vacuum thru each carb the same so like one cyl will be
trying to idle faster than the others or slower. Makes the idle really
rough."

i havent tried to do anything to it yet. he also told me his mechanic said he could turn some screws to fatten up the bottom end.

rider123 · « **Reply #3 on:** February 13, 2006, 01:21:17 PM »

Actually if the bike pulls harder when cold than hot then it's TOO RICH. If down low is what you're looking at turn in the mixture screws in a bit will fix it. Make sure the bike is fully hot to adjust the screws. If it's hard to adjust when it's hot. When cold turn in the screws an 1/8th of a turn at a time and ride and see if it gets better. The mixture screws mainly control low rpm and low throttle fuel/air mixture levels. It would explain you're poor milage.

Also 45 pilots seems a little large but I don't know all your setup. I think the standard G1 Bandit is 37.5 which should be fine with an aftermarket exhaust or stage 1. With a stage 2 maybe up one size to 40. Seems a little large to me if that is the actual size. DO you have pods on there or is it a stage 1 with the airbox still on there.

kedeg_97B12 · « **Reply #4 on:** February 13, 2006, 05:44:11 PM »

Let us know whether you have:
A)Stock airbox
B)K&N replacement
C)Pods
We need confirmation on the following:
Main Size
Pilot Size
Needle position (ie number of shims OR e clip position)
pilot screws turns out from lightly seated

You are going to have to pull the carbs to see what main/pilots you have. You will also need to see if you have the stock needles or a aftermarket set. Without knowing this you cannot diagnose anything.

This is the only reliable way to know what "jet kit" u have. Do this, report back, and we'll get ya set up.

ridemoto4life · « **Reply #5 on:** February 25, 2006, 10:58:26 PM »

i have k&N pods on it. i just put new exhaust gaskets on and i know its not leaking but my bike still pops when downshifting. now the bike does that funny thing at 5500-6500rpm it doesnt wanna stay at a constant speed but if you rev it it will go but it kinda sputters for a second.

Red01 · « **Reply #6 on:** February 26, 2006, 11:31:14 AM »

Some popping is normal on decell... but the other thing is caused from your jetting being off.

ridemoto4life · « **Reply #7 on:** March 01, 2006, 10:58:20 AM »

i was hoping that wierd thing would maybe be from dirty carbs or maybe a bad filter. so do bandits have fuel filters? i still havent done much work to my bike. were are the screws i need to adjust to fatten or lean up the bottom end

Red01 · « **Reply #8 on:** March 01, 2006, 12:08:57 PM »

The fuel filter is in the tank as part of the petcock.

This is the air/fuel screw:

ttewejnodnarb · « **Reply #9 on:** March 01, 2006, 01:21:58 PM »

Not to insult your intelligence, Moto4life, but I wanted to throw in that you need to be on your back looking up at the underside of the carbs as they are installed on your bike to catch a glimpse of the screws. The caps should have been removed already if you have pods. You might want to get a small swivel mirror with a handle if you don't already have one.

...BTW, my carb doesn't have that disembodied fingure hanging from it like in the pic

ridemoto4life · « **Reply #10 on:** March 01, 2006, 08:24:52 PM »

thanks alot guys. so do i turn them in if i want to lean it? my bike pulls harder down low and alittle in the mid range. when the bike is cold. but im pretty sure my top end is the same. no offence taken, im pretty damn smart with cars, ive never really needed to work on my bikes and its the only thing wrong with it so it sticks out like a sore thumb.. one more thing, kinda wierd but some guy here used a little .gif file for a avatar and it was a storm trooper humping and i always thinking how funny it is when im on the forum, so who has it i wanna see it again

99er · « **Reply #11 on:** March 02, 2006, 10:20:17 AM »

It really bites when you get a bike that has had a jet kit installed and the owner hasn't a clue as to what is in there. You need to start at the mains. Ignore the idle screws for now. If you've got pods, make sure they're clean and oiled properly.

Get it warm and up to about 5K in second gear and slam it. It should run all the way to redline with no hesitation. If it hesitates or seems to loose steam on the way up, too lean on the mains. Another good way of diagnosing lean on mains is to full throttle for 10 seconds and then let off to 1/2. If the bike lunges forward, you're lean.

I've varied my mains to two steps rich and, although power is a bit down, there were no ill effects. Best to check for lean.

Next, check your pilots. Stock 37.5s work OK but it's crisper with 35s. Bandits vary somewhat, though. At any rate, YOU need to know.

Next, if you've got that classic leaness near 4K or hesitation at part throttle cruise, raise the needles one shim at a time. Adjust the idle screws to best very low idle (so that the idle circuit only is in play) and then raise the idle to about 1200.

All this should get you running well. It's important to get the mains perfect. They affect most other circuits.

This is my experience and has worked well for me on my '99. YMMV.
Marc/Atlanta
2" mod
K&N
35 pilot
135 main
Holeshot needles

kedeg_97B12 · « **Reply #12 on:** March 02, 2006, 10:59:49 AM »

Quote

We need confirmation on the following:
Main Size
Pilot Size
Needle position (ie number of shims OR e clip position)
pilot screws turns out from lightly seated

You are going to have to pull the carbs to see what main/pilots you have. You will also need to see if you have the stock needles or a aftermarket set. Without knowing this you cannot diagnose anything. Wink

Not trying to harp on it but...If you have pods it takes approximately 4 minutes to pull the carbs to check your jetting. I think it would be less time to pull it and note needle position and jetting than make a guess and try to compensate for the unknown.

You can end up chasing your tail, this I know.