fouling plugs

Energy One

EJ

Member
I have a 02 bulldog and have fouled the plugs several times. i aint had the bike very long and cant figure it out. I think it might have something to do with the choke but when i pull the plugs out they are black. Maybe i am running the wrong kind of plugs or not gapping them right any info would be helpful thanks.....
 

Oscar Maldonado

Guru
Calendar Participant
I've never used the choke on my bike. A couple of twists of the throttle and it fires right up. As far as the gapping it should be .040.

I'd say replace the plugs, and start the bike without the choke, take it for a cruise then check the plugs again. It could be a carb adjustment might be needed.

Although I could be wrong as usual. Hang tight others will chime in.
 

EJ

Member
When i drove the bike to buy it the thing was cutting back so we pulled out the plugs and they were fouled so the guy took it to the big dog dealer and they said it had trash in the carb. they cleaned it out, adjusted the carb, and changed the plugs. He shipped the bike to me and when i got it the plugs were fouled again when the delivery guy pulled it off the trailer the choke was on. just trying to figure it out thanks...
 

woodbutcher

Mr. Old Fart member #145
Staff member
:hi: also, make sure you turn off the petcock overnight. use the enrichener (choke) only as a last resort. could this be related to low voltage from the coil?:up:
 

Raywood

The Pirate
Staff member
Calendar Participant
Troop Supporter
As Woodbutcher says don't use the "enrichener". You bike doesn't have a choke, it has and enrichener that pours plain fuel down the throat where as a choke cuts of air!!!

Hard to believe but "You are fouling the Plugs" using the enrichener. Check your accelerator pump and ensure it turned out only 1 1/2 to 2 turns and give it 2 or 3 twists to start. Use the enrichener as a last resort and as soon as it starts shut it off.

Once you get the hang of starting it with out the enrichener it will be easy and you won't have fouled plugs.

Welcome to the site,
Ray
 

backon

Member
I have the same bike I never use the enricher or the same thing happens to my plugs 2-3 throttle twist's and it should fire right up.
 

woodbutcher

Mr. Old Fart member #145
Staff member
:hi: as far as tuning the carb or setting the accel pump check this site,


http://www.sscycle.com/modules/instruction/uploads/51-1012.pdf :2thumbs:

for proper starting: 1) turn on petcock
2) turn on key
3) make sure dog is in neutral
4) press run button and let the speedo cycle
5) make sure dog is in neutral
6) two twists on the throttle
7) press the start button
if dog does not crank, repeat steps 5,6,&7 until it does. use the enrichener only as a last resort and then when it cranks, turn it off and use the throttle to keep it running until it is warm. AND LISTEN TO RAYWOOD, he knows his sh$t.........
 
Last edited:

Cobrafast1

Active Member
This is really strange. I use my enricher to start all the time, but then turn it off immediately. My plugs are perfect. I've never had them foul in the 15 months I've owned the bike. And it's a 2003 chopper. They are a nice dark chocolate brown.

I think your problem might be in the mismatch between carb adjustments and jetting and the pipes you are using.

If they are the stock pipes, then the problem is definitely in the carb. If the pipes are after market replacement, then rejetting might fix your problem.

You might also be getting oil vapor in the carb from the top of the heads. If that is excessive, then the oil getting into the gas mixture will foul your plugs. Take off your air clearner and check the plate in back of the air cleaner. If coated with oil residue, that might be your problem. A good puke tank hooked up properly will solve that problem. The puke tank will keep oil vapor from entering the air cleaner and carb.

Another thought might be the gas you're using. If you use Mobil, it will foul the plugs. Mobil has some additives for cleaning fuel injectors and that gets on the plugs. Great for cars, but for bikes, it can be a problem. Stick with premium Sunoco, Shell, Chevron and good brand names.

Keep us posted on what you find. We all can help you and that's the purpose of the forum.
 

EJ

Member
Well guys i just got back from a 30mi run and the bike ran great until i got home and let it sit there and idle. The bike then choked down and smoke came out of the air cleaner. I fired it up and smoke came out of the pipes. The bike was at the big dog dealer (supposedly) before i bought it and had the carb looked at. I then pulled the plugs out after my ride and they were smut black. I did not use my enrichner at all. any help would be useful..
 

surferdude

dry docked
I had put an after market enrichner knob on my dog ... had to when I installed a sidewinder intake ... the knob did not sit all the way down and sometimes would work it's way up and make the dog run rich ... so I modified the knob and no more problem ... :bang:
 

Gas Man

Cool isn't cheap
Calendar Participant
Have you adjusted the carb at all? Maybe you need to dial it in for your idle air/fuel mix. Also maybe check the jetting. Here's some tips


Gas Man said:
Gas Man said:
on the adjustments... will paste in a layout on how to adjust the carb
Gas Man said:
Also include S&S adjustments
S&S Shorty Carburetor Adjustments

S&S Carb Manual
http://www.sscycle.com/modules/instruction/uploads/51-1012.pdf



Gas Man said:
Exactly... if you can't adjust it with the accel pump then you need to go bigger on the int jet.

You can use the "remove your carb" thread to help get to it... look at post #1,2,7,8 to aid you in getting to your jets. No need to remove the carb... just have to drop the bowl.

To adjust the carb... with the bike warm...
(in=clockwise/out=counter)

if your idle is low... turn it up a bit...

now spin in the accel pump screw till it seats.

now spin in your fuel/air mix screw till the motor sounds like it wants to die

now spin it back out counting 1/4 turns. Do it slowly to give the motor/carb time to adjust. Do this till the motor sound like it wants to die on this end. Now you have counted those turns and you have say 2.5 turns. Spin it back in 1.25 turns. Or middle to almost dead on each end.

Now adjust your idle to 1,000 rpms on the tach.

Now spin it out 1.5 turns

Now with a few quick stabs at the throttle see if the rpms come up fast like you would think or if it kinda hesitates then takes off. If it does hesitate then spin the accel pump out another 1/4 turn and repeat till you get what sounds good.

If that don't fix the sneeze... you can spin out the accel pump a bit more... but anything over 2.5 turns means you need a larger intermiediate jet.

Now on the plugs... to test run the bike and see if the jets are good.

Check or replace plugs.

run the bike but keep the RPMS below 2500... then don't let it idle and kill the motor, check the plugs. That is to help check the int jet.

Then take it out and run it hard... keep the RPMs up and romp on it... then on a striaght patch of road with the RPMs up high (over 3k, or even higher) kill the motor with the OFF switch. Pull the plugs and check. that is to test the main jet.

The idea here is that your int jet runs from idle to about 2750. Then the main kicks in from there out. That's why we say your run mainly on your int jet. main is only for romps.

Use this GUIDE to read your spark plugs.
 
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