Running rich before pods. Running rich after pods. Why?

[alex f]

so my 82 has the bs 34s with stock jetting which by my understanding runs lean very easily. It was running way rich with air boxes but ive since dropped it after into a hardtail frame, put pods on, and opened up the exhaust. Ive also installed hughs cdi system because my old ignition was shot. I did not rejet because i wanted to see if the open airflow would push it to the lean side. It did not. Im running just as rich. In theroy upping the jet sizes will make the mixture even richer right? So why would my mixture show no change after modifying the intake and exhaust? My only thought would be float levels?

 

[system9]

I am currently experiencing a similar situation. I went from pipes with a smaller diameter to larger pipes with a free flowing exhaust. Although my carbs are not the same as yours, the symptoms are. It was acting rich, but I first mistook this as lean, because I thought there was no way it would run leaner with the bigger pipes. So I went a step up on my pilot jets, and after that the bike almost won't idle at all. I have ordered smaller pilot jets, never thought I would need them (I have plenty of larger ones) so I will let you know if the bike runs better with the larger pipes and smaller jets.

 

[Bob Kelly III]

that is odd but not totally unheard of.... it could have been running like 2 sizes too rich to begin with.... and now your only one size too rich
that sort of thing...... I would suspect float level too !
......
Bob........

 

[5twins]

Yes, check the float levels. But, before taking it apart and measuring them, check the fuel level with the clear tube held up alongside the carb. It's pretty easy on your carbs because they have a fitting on the bowl next to the drain screw for the hose. gggGary just did a nice thread on this. Ideally, you want the fuel level in the hose right around the float bowl to carb body seam, not too far above or below it. If the level is high but the floats measure correctly, check the o-ring on the float needle seat. It can let extra fuel into the bowl if it's bad.

Another thing to check would be the assembly sequence of your needle in the slide. Make sure the spacer washers are in the right spots and that the little spring is on top .....

If the little spring was put under the spacers and e-clip, the needle would sit too high and run rich.

 

[alex f]

Yes, check the float levels. But, before taking it apart and measuring them, check the fuel level with the clear tube held up alongside the carb. It's pretty easy on your carbs because they have a fitting on the bowl next to the drain screw for the hose. gggGary just did a nice thread on this. Ideally, you want the fuel level in the hose right around the float bowl to carb body seam, not too far above or below it. If the level is high but the floats measure correctly, check the o-ring on the float needle seat. It can let extra fuel into the bowl if it's bad.

Another thing to check would be the assembly sequence of your needle in the slide. Make sure the spacer washers are in the right spots and that the little spring is on top .....

If the little spring was put under the spacers and e-clip, the needle would sit too high and run rich.

Thanks 5twins. I also noticed the rubber seats for my chokes on each carb are slightly dry rotted and look aged. Could this be causing a condition where im always slightly choked?

 

[5twins]

Yes, that's possible too.

 

[weaselbeak]

All needles & seats are subject to variation in their ability to seat. The clear tube method is the only way to know for certain exactly how much fuel is in your float bowls. I don't trust any other method.

 

[fredintoon]

so my 82 has the bs 34s with stock jetting which by my understanding runs lean very easily. It was running way rich with air boxes but ive since dropped it after into a hardtail frame, put pods on, and opened up the exhaust. Ive also installed hughs cdi system because my old ignition was shot. I did not rejet because i wanted to see if the open airflow would push it to the lean side. It did not. Im running just as rich. In theroy upping the jet sizes will make the mixture even richer right? So why would my mixture show no change after modifying the intake and exhaust? My only thought would be float levels?

Hi alex,
before fussing about float levels, for all that they say XS on their ends those pleated tapered pods will fuck up the stock carbs airflow.
They may work with roundslide or flatslide carbs but the stock carbs are only happy with the stock airbox or with Unipods.
You've also merely sawn off the bikes exhaust to leave shorty headers. You gotta extend the headers towards the rear wheel a fair bit
(muffs or straight through, but it's the length that's important) to get the exhaust resonance right.
After that's fixed, then fuss with the float levels.

 

[gggGary]

Orings on float valve to carb body brittle let fuel bypass valve.