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Discussion Starter · #1 ·
Took the bike out to make a quick trip to the auto store. On the way there the bike ran fine, on the way back I managed to run out of gas. Put it on reserve, made it to a gas station and filled it up. Went to fire the bike up and it didn't want to turn over at all, actually managed to kill the battery and had to get a jump. After the bike started it was idling real rough and ran like crap.

Little background: I bought the bike in March and it has sat with gas in it until now. I have no idea how long the gas has been in the tank but it ran fine last weekend and today until I filled up. I put some SeaFoam in the fuel right after I filled up but before I tried to start it. I filled my truck up this morning at the same station and I haven't had any problems (truck uses premium too).

Any ideas on what it could be? I am new to carbureted bikes so this is like black magic to me. I guess the first place to start would be to pull and clean the carbs, anyone have a decent write up or can point me in the right direction on how to do this?

On another note how do I know if the bike is running rich or lean? Is it as easy as pulling the spark plug and seeing how it looks? The bike backfires a little when I downshift at higher RPMs but besides that seems to be okay.

Any help is greatly appreciated.
 

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Sounds like a fuel problem. Plus, you might have sucked a little trash or water when you ran out of gas.

For a proper plug check, you really need to run the bike at the throttle position that's problematic. 1/4, 1/2, WFO or whatever. Mark the grip and throttle housing with tape as reference. With engine warm, run the bike at the desired position steady, pull in the clutch and kill the engine. So you need tools and a good stretch of road.
 

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Discussion Starter · #3 ·
Took the carb off yesterday, was actually pretty cool to take it apart and learn how it works. The plus side is the carbs looked super clean, no signs of crud or gunk anywhere, not too bad for a bike from 2004.

I took out all the jets and needles, blew/cleaned them out and made sure all the passage ways were clear. It looks like the bike is running stock jetting: 170 main, 50 pilot and the needle was on the 3rd clip (I moved it to 4th). Fuel screw is 2 turns out.

Bike is still difficult to start up, I actually have to crack the throttle a hair to get it started. After it starts I can release the throttle and the bike runs but it still sounds like it isn't running smoothly. When I filled the tank I used 93 octane and about 5-6 ounces of Seafoam, these bikes run high octane fuel correct? My next step is to adjust the fuel screw to try and get the bike to idle properly and take it for a spin around the block. If that doesn't work I guess I will drain the tank and try to refill it.

If anyone has any suggestions I'm all ears, and if anyone could recommend some jetting numbers that would be great. I have an FMF slip-on and K&N filter.
 

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stock main is 175, pilot jet is 30 and 3rd clip....u might have it running a little rich, so check ur plug and make sure its not all black and sooty also try running ethanol free gas..mine ran like crap if i didn't.
 

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Discussion Starter · #5 ·
Really? For some reason I could have sworn the stock 04 bikes came with a 170 main and 50 pilot :headscrat

Anyways I talked to the good fellas over at Halls Cycles and he said it sounded like I may have water in the gas or a fouled plug. Guess I will drain the tank and fill it up again and check the plug.

Does the ethanol gas really screw with the carb?? There is nowhere around me to get straight gas which really sucks.
 

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The manual says 175 main 30 pilot and clip 3rd from the top. Fuel screw 1 3/4 turns out. Mine runs fine on ethanol BTW.
 

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Discussion Starter · #8 ·
Yesterday I pulled the spark plug, it is definitely running rich but the plug didn't look oily or anything. Cleaned the plug off and took it for a ride and the bike is running horribly. When I open the throttle the bike feels like it is cutting out, it will start to sputter and die then pick up again. It feels like the bike is jerking back and forth and misfiring. Sometimes when I opened the throttle the bike wouldn't accelerate at all and then all of a sudden it would jerk forward.

What I don't get is why this is happening now? The first weekend I rode the bike it ran like a top, no misfires and it pulled hard throughout the RPM range. At this point I think it has to be a bad tank of gas, I am going to drain it and refill it and drop in a new spark plug.

Also going to order the jetting kit but damn it's expensive heh.
 

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Ditch that gas and change the plug like you said. Also, does it run good at any throttle positions? If it does, use that as an indication of which jetting circuit is acting up.
 

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Discussion Starter · #10 ·
It's throughout the rev range. When I am WFO in 4th gear it runs a little better at higher RPMs but below that it's a dog. Hard to rip it into 5th and 6th in the city streets especially when the bike is acting up like this...

Will drain the tank tomorrow or Saturday and replace the plug. Is the NGK CR8EB a pretty standard plug or do I have to pick one up online??
 

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Discussion Starter · #12 ·
Drained the tank and filled it with 1 gallon of 93 octane. Added a shit ton of carb cleaner and water dryer to the gas as well. Cleaned the spark plug and fired it up. Bike still ran like poo so I pulled the spark plug and it was oily black, guess I am running rich.

Pulled the carbs and soaked everything down. Re-checked the jetting, I have a 175 main, 30 pilot and 50 idle jet. I pulled the needle and moved the clip to 2nd from top. Cleaned the plug again (no one had a new one in stock :rant:) and fired it up. Happy to say the bike runs like a champ now.

Two things I noticed: there is a slight hesitation when I go from closed to open throttle and the bike pops when I am in high RPMs and shift up (3rd to 4th, 4th to 5th, etc.) Could the bike be running too lean now? I am going to order some plugs online but it will take a few days to get here.

I also managed to lose my entire kick stand assembly during the test run :damn: I put locktite on the bolts when I installed it last week and I still lost it...
 
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