Jetting for stock exhaust and pods

[1wyatt2]

Im working on a 79 gs 1000 stock jets 95 main 15 pilot, I'm looking to run the stock exhaust with pod filters. Any ideas of where I should start for mains and needle jets
I also have a 4-1 header if I threw this on by itself where would I start for main jets and needle jets Thanks

[azr]

I've thrown a Marvin 4 into 1 on my 1000 and kept the stock 95 jets, did try 102.5 but found the 95's to work better, the bike had stock airbox and filter. Another fella with the exact same set up had his bike run better with 102's, that's how it is, every bike is individual. We also need to know what 4 into 1 you are thinking of putting on. Sorry no advise on the pod question but really you can just put them on and go from there, I'm guessing you're trying to order parts before hand so you don't have more down time than necessary? If you're going to do pods and pipe you'll need a Dyna stage kit.

[1wyatt2]

Kerker 4-1 header

The header I was looking to use is a Kerker 4-1. will there be much difference in jetting between stock exhaust with pods or Kerker header and pods. Any ideas for a starting point.

[OldVet66]

If you go with the Kerker pipes with pods I would use the Dynojet 3304 stage 3 jet kit. Start out with the DJ 138 jets. The needles are the trick with this jet kit, better than the Mikuni needles for this type of modification. DJ also marks their jets differently from Mikuni. I have never just done pods with stock exhaust, but pods make the biggest change, (more air intake) and require more aggressive jetting to balance the lean condition created by more air. DJ also makes a stage 1 and 2 kit that would cover just pipes or just pods. Before you make any changes, get your bike running perfectly, so you have a base line for comparison. I love the ease of access and air box tool kit, but it seriously was not worth the effort to get the jetting right. Even with a jet kit for the application, jetting for pipes and pods is a PITA.

[azr]

This is more of a question for me, the main needles in the VM carbs are adjustable, two above and two below. The DJ needles are as well but are the DJ needles a different size as well? I'm just wondering if there is a need to buy the DJ kit or just buy larger main jets and move the clip on the original needle.

[Big T]

You should be able to rejet the carbs without a DJ kit

But, as someone noted above, every bike is different

[OldVet66]

The DJ needles have a better taper that is designed for 4-1 pipes and pods. I have never seen a side by side comparison between DJ and stock Mikuni parts, but I understand it's harder to get dialed in with the Mikuni needles.