frustrated

[allenmp]

I have a 2003 bdm chopper with a 107" I bought from a brother in law this will be my third year with the bike. When my brother in law bought it outta south carolina I had never heard of bigdog but in the two years he had it it was very reliable and not to mention how it looked so when he decided to sell it there was no question I wanted to buy it he just had the 20k service done bdm put a new.frame I thought this was an awesome bike so I bought it from him. Then I went to cassiday ks and on my way home
I had an elec. Problem so I had to trailer it home the mechanic at okc told me my ehc failed so I hired him to do a.wire plus upgrade not a good idea after him having my ride for the whole riding season and multiple trips to the city and back and still not right me and a friend used the info off this board and went to work. We toom all the skins off to get recleared and shipped the carb to xxx we chased wires found some shitty work I paid to much for and fixed things. I had xxx rebuild my carb and bore the venturi and put a booster kit in we put the bike back together and runs awesome just not as good as I want so contacted xxx he thinks I am not getting enough air so I get a dual runner and install it runs great for awhile then wheel bearing goes out so I take it to a different shop and while he has it I had him rejet the carb since the new intake allowed more air bu now I finally made it to cassiday and back I think the elec.issues are good but while I am riding if I hold constant speed it sputters like a sob here is what I have
At an idle hard to explain sounds like only hitting on one cylinder
Speeding up awesome
Holding speed sputters and spits like hell
If I let off smooths out
If I throttle hard smooths out and takes off awesome
Only at idle and constant speed
My plugs are cinnamon in color after adjusting carb
the ahop said timing is good and not sucking air anywhere
Not sure exactly what jets he uaed said he went up a size
With hard throttle takes off very good
Starts easy with no backfire unless its cold
I dont use enrichment
Always 91or better octane gas
tried loosening gas cap no change
New plugs and wires all tight
New voltage regulator had stator and censors checked all good
All new switches coil etc etc installed by so called bdm tech
Hi 4 ignition
This bike dynoed 111hp and 114tq before carb and intake I wanted to dyno it again but the spitting and sputtering wanst clearing up
Its a 2003 chopper 107" dual runner intake V & H big radius 2 into 2 pipes I have had it to 3 different shops and they make it go awesome for a little while then back to this I have almost sold the bike but I love my chopper and how it feels to ride it but this is pissing me off any suggestions are greatly appreciated sorry for the long story just wanted to let ya know where I am at with this thing I wont pay someone to fuck.my bike up a.d have got alot of good info off this board but I can seem to vet this prob pinpointed
Thanks for listening
Mike

 

[Srodden]

S and S has a carb quick guide on there website. Sounds like if it spits out the air cleaner that is a lean condition. There's a diagnosis that you can do yourself to check for a rich or lean condition check it out.

 

[Th3InfamousI]

lean brother ....drop the bowl and report back what you got in there. At minimium you need a 31 inter and 78 main with your carb and air cleaner. But you really just need to go up a bit adjust it and ride it and find what works the best!

 

[allenmp]

I have the s & s manual the website and this board I refer to constantly I keep resetting the carb after rejetting I rode about 100 miles and plugs were white so added some fuel a few times of adjusting and the plugs are staying a cinnamon color on both of them which by everything I see is good after a ride to cassiday and back (300 miles) or so I pulled the plugs and stil looked good even sputtering all the way I did notice if I adjusf for more gas it seems to get worse if for less dont seem to change much at a 1/4 turn at a time its frustrating but I hope to get it figured out I have spent alot of time trying and refuse to pay anyone else to not fix it. But I aint gonna give in I know this bike can be reliable I am just over adjusting or overlooking something
Surely cant be major right?
It hasnt left me aside the road since I put it back together myself with info off this board so hoping to figure this out too
Thanks again
Mike

 

[allenmp]

Ok i.dont think he went at a 78 I will find out he went up one size from what xxx had efore dual runner can I order jets from ss or can anyone tell me a good place to get them as I dont care to give the only place around me my business anymore unless I have to
Thanks
Mike

 

[kmalysa]

I have the s & s manual the website and this board I refer to constantly I keep resetting the carb after rejetting I rode about 100 miles and plugs were white so added some fuel a few times of adjusting and the plugs are staying a cinnamon color on both of them which by everything I see is good after a ride to cassiday and back (300 miles) or so I pulled the plugs and stil looked good even sputtering all the way I did notice if I adjusf for more gas it seems to get worse if for less dont seem to change much at a 1/4 turn at a time its frustrating but I hope to get it figured out I have spent alot of time trying and refuse to pay anyone else to not fix it. But I aint gonna give in I know this bike can be reliable I am just over adjusting or overlooking something
Surely cant be major right?
It hasnt left me aside the road since I put it back together myself with info off this board so hoping to figure this out too
Thanks again
Mike

How does the inside of your tank look? Many Tank liners have failed greenish peeling of liners can block fuel flow.

 

[wyatt580]

Got the same issue just did major upgrade and everything seems fine except for the surging at about 2-2500 rpms...had same issue last time I put the 600 cam in and cylinders shaved...it turned out to dial in air bleed....also bob at xxx on his website mentions the stumling...not clear what it is but has to do with the bowl or accel pump...hope this helps.....if ya figure it out post it up.also the ventri you had put in sounds like it affects the air flow...the guy that did my valves and machine work...said it really messes with the airflow...peace

 

[allenmp]

As for the tank when I had it rejetted the bowl was clean (no inline filter) as for looking in the tank dont see anything abnormal.
May be confused on air bleed adjusting I will read some more and look at l
Jet sizes I am workinv night shift so hard to get anything done.
When I got it from xxx it had a spike breather on it and he jetted but he said that would restrict the flow bad so I might not have put big enough jets for the dual runner this is my extreme lack of knoedge but I figured sin e the plugs look good it must be right as I get around I will check it out and try to get new jets ordered and see if it helps
I appreciate the comments
I will keep with it and hopefully get back to cassiday and dyno it again I am curious to see if anything changed
Thanks again
Mike

 

[francoblay1]

Removing the "Bowl Vent Plug" did help me (together with going up to 0.31 & 0.76 jets). The sneezing went away immediately. All good now :2thumbs:

 

[allenmp]

Ok like I said when I got back from cassiday a couple weeks ago I pulled the plugs and looked good so with everyone telling me I am lean before I dropped the bowl today I decided to pull the plugs and dammit both were white indicating lean condition right?
So I dont know if the temp changing the hunidity or wtf
Anyways I backed my fuel screw out 1/4 of a turn let it warmup good and on my way to work I backed it out another 1/4 turn for the next 20-25 miles to work it ran flawless to pops sneezes nothing but pure bigdog music to my ears
I am not sure what happened or why and may not be good in the morning when I get back on but for this 25 mile ride to work besides the 25 mph wind it was a great ride
I do have one question my air/fuel mixture screw seems to be backed out quite a bit is this normal or do I still need to go up a jet size
Thanks for the replies it has helped me every time I needed them
Mike

 

[wyatt580]

Cool man hope it doesn't come back....if your backed out 2 turns you should go up a jet size...i'm sure someone with more knowledge will chime in....

 

[standuprick]

To check the plugs you have to shut the bike down in the range your having the problem. If you ride 100 miles by the time you slow down and shut if off your getting an in accurate read. Say your having the problem at mid range. 50 mph. Run the bike at that speed, hit the off button and coast to a stop. Pull the plugs. That will show you your mid range. Same for higher speeds or lower speeds. You can be rich in one area and lean in another

 

[Nukeranger]

X2 - and be carefull not to burn the crap out of your hands.

 

[bruce]

If you what to call me, I can explain how carb. works and maybe help you get adjusted right. It seem that you are all over the place with the adjustments and it will be hard to get right that way., main jet is for hard accel., inter. is most of your riding normal accel. and cruising, then a idle mixture screw which is mainly for your idle but does affect other things - if this isn't adjusted right you will get poor mileage, have you removed the plug from backside. phone 717-382-9983

 

[allenmp]

Ty all for the help I am here for the good.company and the bad screwings I took trying to have someone fix my ride the fact is with all the trouble I have had with shitty mechanics and $$ spent trying to fix it on top of the ridicule I wouldnt trade my chop for any other bike out there with y'alls
Help and advise I think I have worked out most of the bs the mechanic left to keep me coming back .
As for my problem like I said most said a lean cond so before taking anything apart I adj fuel and opened a little on acc pump and I ride almost 50mi round trip a day to work and back and yes. And today it ran like it did when I first got it or better. I have held speed 45 -80 and everywhere in between and she just sounds awesome as for mileage I will fill up in the morning on my way home and see what I have if it keeps this up I will put it on the dyno next time in cassiday and hopefully see better numbers than last time
Thank you all again for the replies and all the help
Mike

 

[2004BC]

If you what to call me, I can explain how carb. works and maybe help you get adjusted right. It seem that you are all over the place with the adjustments and it will be hard to get right that way., main jet is for hard accel., inter. is most of your riding normal accel. and cruising, then a idle mixture screw which is mainly for your idle but does affect other things - if this isn't adjusted right you will get poor mileage, have you removed the plug from backside. phone 717-382-9983

Call this man above. You need to adjust/change jets in a logical manner. Your air/fuel screw can't compensate for your main or intermediate jets being to small as with opening up your accelerator pump to full stroke. Bandaids not solving the jetting problem. Your almost there and when your done you will never be dependent on a backyard mechanic again.

 

[allenmp]

I have talked with xxx and he has helped me out on the carb issue its running great for now and getting around 40mpg on my last tank of gas my acc pump screw isnt out much and mixture screw isnt as far out as I thought I appreciate all the help
Bruce if its ok with you I will save ur number for future reference I do appreciate the help
With the working rotating shifts wasnt sure when ur available
Thanks
Mike