I just finished up installing the Fullsac dual exhaust and Andrews EV27 cam install on my 95 glide. I noticed at idle the right pipe has an intermittant blip or pop. I think it was always there just not as noticable. If you put your hand at the end of the muffler you can feel the pop. It does not do it while driving. No decel pop. The rear cylinder has always run leaner than the front. What should I look for?

 

Could be an exhaust valve that has a slight leak or a bad wire/coil/poor electrical connection if it was there before as well. If it wasn't then check out yor pushrod adjustment if they are adjustables. Hope this helps.

 

I re-adjusted the valves. I will go throught them again.

 

I really wouldn't spend much time chasing the symptoms you described. The purpose of the crossover (which you eliminated) was to smooth the idle and give a more constant and balanced flow between the 2 cylinders. They will even seem to miss on a cylinder (usually the rear) when cold or before totally warmed up to a good operating temperature when that has been eliminated.

Rest assured, your rear cylinder will run slightly hotter with that setup. Not a problem particularly, but considering you've changed the cam, you may need to look into re-tuning your carbuerator and possibly going with larger jet(s).

I would be most concerned about the rear plug always looking lighter than the front, even before you changed to true-dual. Without a crossover the rear usually lightens up to match the front or even a tiny bit lighter. And yours was already light on the rear? That's generally a sign of an intake leak on the rear or a ring leaking on the front causing it to darken. But you say you just put the true-dual on and we don't know how much you've ridden to check it out....

 

I agree the bike runs good. I haven't run it long enought to get a reading on the plugs. Since I have always had that popping I would lean towards an intake leak.

 

Somewhere on this forum is a link to an explaination on the dual fire ignition that describes the "pop" similar the one you've mentioned. Search the forum using "dual fire".

Of course if you've changed to a single fire, this response should be ignored.

 

I've seen that thread or post, a long time ago. I don't remember the specifics, or lack of... but if memory serves me, it talks about popping due to unburned gases being ignited during the cycle where the exhausting cylinder is fired same as the compressing cylinder on a dual fire ignition and how overlap of cams affect that.

 

Here's the link

Daytona Twin Tec LLC - Tech FAQ Evo Series

 

Different page, but same info I read. After re-reading, my post was in error - the dual-fire with certain cam overlap can cause a touch of the intake vapor being burned on the exhaust stroke...

Thanks

 

Mine was doing that and i found that the intake gaskets were leaking, causing a lean condition. Spray just a little carb cleaner with a straw at the manifold gasket front and rear heads. (where the Y pipe intake attaches to the heads).