Nothing I do seems to help. Right now it is backfiring through the carb pretty bad, always at around 2500rpm.
Here's my setup: RW exhaust, K&N carb mount, 190 jet, stock pilot, needle on 3rd clip, air/fuel screw 3 turns out. I also looked at my plug a few mins ago(first time I did since new pipe) and the top of it was black from the tip to the first or second thread. I know black means rich, but if I've never checked the plug can I really tell by looking at it. BTW I ran it for about 5-10 mins. So can rich cause popping through the carb??

I've also had a 185, and 195 in it. 195- mechanic said way too rich, so he suggested a 185, tried that and it still wasn't working right. Oh, and I'm pretty much at sea level. Someone please help!!!!!!!!!!!!!

 

If you are running the stock needle you need to move it to the 4th or 5th position. Check buttfungus's website under "ds jetting/mods data", there is alot there that can help you out.

 

Yeah, thanx for all the help guys. I'll check out his page once again. Oh and I am using the Dynojet needle, not stock, I forgot to mention that.

 

With a carb mount filter my guess is your runnin lean, at sea level id go with a 200 main, should be the largest that came with your kit, you can do experiments by wrappin duct tape around portions of your filter, if it runs better with parts tapped over than your obviously runnin too lean, if it runs even worse, your runnin to rich, i run full exhaust , and a twin air filter in the stock location but lidless and lots of holes in airbox, at 1000' and run the dynojet 200 main with needle on third needle possition and still run a bit lean, but the 200 is as big as i got for a jet.
Rob.

 

OK.. 3rd notch from the top and dyno jet 195 . That should be the correct jeting!

 

Make sure you carb is all the way in the boot going on the intake manifold (mine has popped off twice in the last 2 yrs). Also check the slide on the carb, I found mine was stuck at half throttle and was pulling my hair out trying to get it to run decent down at low rpm's.

 

Where is the slide, and how do I know if it stuck???

I swear I get all kinds of stories, first one person(a mechanic, that should know his stuff, but might not) tells me its way too rich with the 195 in, now I hear otherwise. What should I believe????????

Looks like its back to the 195 for another try.... Can someone please tell me how to read a plug correctly.....how long the bike needs to run, at what speeds....etc Thanx for all the help guys.

 

The slide is what the needle clip's into and is pulled up against the spring by vacuum, it is under the cap on the top of the carb....................


...the needle affects carburetion from about 1/4 to 3/4 throttle, and overlaps the pilot circuit and the main circuit, the lower the clip on the needle the richer,also the taper of the needle affects ratio, thicker taper=lean, thinner=richer,one of the way's to check the different circuits is to run the motor in the specific range you want to check, idle, mid,and wide open throttle, then pull the clutch and stop the motor, do not coast or idle the motor as it will change the color of the spark plug, pull the plug and check its color, light brown is good, black powder carbon=rich, white flaky ash=lean, set the main jet first as it has the most overlap, change one jet size at a time,then recheck, after the WOT looks good,then run at mid throttle, shut down the same, check the plug and adjust needle as required,typically if the motor idles smooth and does not hesitate the idle settings are ok....this is kind of a condensed version that I found at "http://204.71.0.3/motoprof/moto/mcycle/carb101/carb101.html"...many thanks go out to fine people who provide this important info.

Bajads650....I am running the Trinity pipe with a 190 main, 45 pilot, needle clip in #4 last groove at the bottom,gas screw 3 turns out, stock filter with lid removed, and it is running perfect, I would think that with the Woods pipe which is less restrictive than the Trinity and the carb mount K&N that maybe even the 195 may be to lean, but the main really only affects the the throttle from about 1/2 to WOT, so if is popping at 2500 rpm, not to say can't be at WOT at 2500, I would look to pilot jet or the needle position, I work in woodburn so if you ever need a hand give me a call on my cell #503-580-9134........good luck James

 

my slide was scuffed up and sticking after I cleaned it up with carb cleaner and re-installed it was fine. the slide is under the cap on the top of the carb as previously stated. Also make sure the needle is fully seated and all the spacers are in thier proper position.

 

This issue comes up about twice a month on this site so you may want to do an advanced search an see what others have done. OR
Generally speaking everything posted here has truth. The only problem is, you may have something else wrong. a few questions;

1) has the problem been the same since you started troubleshooting it? (popping around 2500 rpm)
2) Will the RPM go over 2500 or does it sputter to bad to let it
3) What throttle positions does it sputter at (wide open, half-full, only part throttle)
4) Did it ever run good with the new pipe/filter or did this start since you put it on?
5) Have you tried new plugs?
6) Have your valves been checked for clearance?
7) Have you checked your intake boot for cracks?

Lots of questions but without knowing more about your situation its all a guessing game and that can get expensive for you. [img]i/expressions/face-icon-small-wink.gif[/img]