[Snowdust]

I recently added Cobra Slashdowns to my 900. Had the usual pops and ocasional backfires. Added the marble and that helped a little. Decided to do all three and added a PCIII and BAK and had the PC set to this combination. Backfires are back. Should I add the marble back to the new hose installed or try to work it out through the PC.

 

[V-Twin]

Marbel it back. It'll sound much better and will minimize the poping again.

 

[ophidia]

What I did on both my bike and my buddy's 900 was pull off the hoses where they go into the heads and marble there, then put them back on. It worked a lot better than marbling at the end of the hose that goes into the air cleaner. There must be enough give in the hose where some air still gets sucked in when there's only a marble at the end. It eliminated popping pretty much entirely on both bikes.

 

[Glenn Sparks]

Tried it on my bike today, and man what a difference it made.Thanks ophidia for the advice.

 

[mittens01]

Which hose are you sticking the marble in?

 

[ophidia]

If you look at the front top of the front head, and rear top of the rear head (right side) you'll see a 1/2"ish hose attaching to the head. Just pull it off of each head and stick a marble in it, then hook it back up.