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Pods, Pipes, Panic! (Help! Your Bike has Pods)

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    Pods, Pipes, Panic! (Help! Your Bike has Pods)

    Since a PPP post (pods, pipes, panic!) comes up almost daily, let's get some basics down about pod filters and exhaust mods.

    What's Wrong With You?!?

    First, changing your bike from stock makes you a terrible person and is a direct cause of erectile dysfunction, famine in the 3rd world, and all other human suffering. You are literally a monster.

    With that out of the way, here are some things to know about your new role in this world as a villain.

    Do I Really Need to Rejet?

    Yes.

    Suzuki set the jetting for these bikes based on the stock airbox and stock pipes, generally a 4-2 setup. Changing the parts at either end of the system affects your carbs. Open pipes or a 4-1 allows more airflow out of the engine, reducing back-pressure. Pod filters permit air to enter the carbs faster than the more restrictive stock airbox. The amount of the increase depends on the mods. Generally, changes to the pipe add less air than changes to the filter. These changes accumulate, so adding a pipe may require only a little adjustment to you existing jets, adding pods definitely will require jetting changes, and going with pods and a pipe absolutely requires substantial adjustments.

    Say a Proper Good-Bye to Stock Jetting.

    Before you change your setup, get the bike running with the stock parts if at all possible. It is much easier to adjust jetting from a working baseline. If your carbs are dirty and clogged or your valves are out of whack, you will lose your mind chasing those problems down while simultaneously figuring out new jetting.

    Even if your bike runs well, you need to clean those carbs and make sure your valves are right. There is no escaping this. While you're in the carbs, take stock of your current jetting. No one here can tell you what jets you need unless you tell us what is in there now. If you have a stock setup, you probably have standard jetting, but who knows what's happened in there over decades of PO abuse. Compare your jets to the stock specs here.

    If you can't reset the bike to stock (my bike came with a 4-1, for instance), you need to cuddle up with these specs and your current jetting for reference points.

    OK – I am Ready for Mayhem. Give Me Jets!

    Slow down, killer. If it were that easy, we would not have PPP threads every day.

    Remember, the changes you make to your bike dictate the changes you need for jetting. There is no simple rule for what jets and sizes to plug into your bike. This post has some pretty good info to find a starting point. You can also SEARCH THE FORUMS for threads on Pods. If reading that pile of nightmares doesn't drive you into alcoholic despair, you might find some jetting help there.

    "Choose" Your Weapons

    Your carbs present the first crossroads in your path to evil – CV or VM?

    CV – Breakdancing in your Members Only Jacket

    Bikes with the new-fangled CV carbs may get to (or have to) use the crutch of a DynoJet kit. The good news is that some smart dude put together jets and other bits for your bike. The bad news is that costs money AND you may have no other choices since the stock needles for those carbs often are not adjustable and/or have tapers that don't play well with all that breezy air. DynoJet has your starting point here.

    Basically, if you go with pods or pods and pipe, grab that Stage 3 kit. It will get you very close, but plan to make further adjustments.

    VM – Disco Never Died

    With hipster VM carbs, don’t be too smug. Sure we have more game with the ladies, but there's good news and bad news for us as well. Our needles usually (but not always) are adjustable, so we are not slaves to the DynoJet cult and can spend that money on bell-bottoms and lava lamps as God intended. OTOH, we get no short cuts or pre-packaged kits to launch our jetting adventure.

    BTW – if another person tells me to "just get a Stage 3 Kit" for my 1978 VM26s, I will not be responsible for the ensuing bloodbath.

    So we have even more trial-and-error to work through. Based on your mods, figure out roughly how many sizes up you need that main jet to go. That linked guide suggests +6 sizes for pods and pipes. My GS750 stock mains were 100, and I am running 117.5 now, but stay tuned for changes.

    With a target size in mind, order main jets at -1/0/+1 of the target size – so if you think my jetting might work for you (I wish it worked for me) – order 115, 117.5 and 120 mains.

    For pods and pipe, you need to raise the needle usually around 2 notches – i.e., move the clip 2 slots down.

    For the pilot, you might be OK with the stock size, with just some re-balancing of the pilot screws to shift towards more fuel. If not, you may have to increase the pilot size one step, or even two.

    More to come.

    #2
    Great write up, buddy.

    Just the thing for novices to learn a little about how to make that old bike haul a** or at least be noisier.
    80 gs1100 16-v ported & polished, 1 mm oversize intake valves, 1150 carbs w/Dynojet stage 3, plus Bandit/gsxr upgrades

    Comment


      #3
      Really nice. Well written . Break dance and disco, what a fitting analogy for a timeline!

      Comment


        #4
        Well said, one thing I have stumbled on is a bike with Pods and a stock exhaust. Best set up?

        Comment


          #5
          Was that a rant or a great post that should be a sticky? I say sticky, but that's only my breakdancing, members only jacket with red louvered sunglasses wearing, disco is dead, CV carbs are boss opinion on the sublect.

          Comment


            #6
            I remember reading this in a few places and wondered if it was actually a legitimate thing to do when re-jetting:

            1 jet size for custom 4 into 2 exhaust

            2 jet sizes for 4 into 1 exhaust

            1 jet size for K&N filter (single inside airbox)

            1 jet size for drilling out the bottom of the airbox

            3 jet sizes for individual filters

            2 jet sizes for no muffler (open header)

            1 pilot jet size for every 3 main jet size increase

            Add up all the jet size increases and subtract one. (Remember they go in steps of 2.5 for each jet size)

            Comment


              #7
              Imagine if someone were crazy enough to start an Excel document with each tab for a different GS and Carb (e.g. 77-79 GS70 VM26) and a spreadsheet with columns for filters/pods, pipes, pilot, main, airscrew, fuelscrew, needle setting etc and a notes column for any issues they noticed/spanners they threw. In case anyone wants to tell me I'm an idiot here's some ammo: 78 750, K&N's, V&H 4-1. Going to start off with 125 main, stock pilot, fuel needle one notch down, fuel screws to pre-made notches that vary from 1.6 turns to 1.9 and air screws at 2/ 1/4 turns. Feel free to tell my why the settings won't work (besides playing with airscrews).

              Comment


                #8
                awesome write up - looking forward to the more to come. already learned a lot, like my 78 vm26ss probably won't either take a stage 3 kit. see? you just saved me 100 bucks!

                +1 for sticky. and i dig your style, cat!

                Comment


                  #9
                  Originally posted by Benny78 View Post
                  Imagine if someone were crazy enough to start an Excel document with each tab for a different GS and Carb (e.g. 77-79 GS70 VM26) and a spreadsheet with columns for filters/pods, pipes, pilot, main, airscrew, fuelscrew, needle setting etc and a notes column for any issues they noticed/spanners they threw. In case anyone wants to tell me I'm an idiot here's some ammo: 78 750, K&N's, V&H 4-1. Going to start off with 125 main, stock pilot, fuel needle one notch down, fuel screws to pre-made notches that vary from 1.6 turns to 1.9 and air screws at 2/ 1/4 turns. Feel free to tell my why the settings won't work (besides playing with airscrews).
                  Those are good starting points, but you may still need to fiddle around.

                  I have the same bike and mods. 125 mains were too big for me, and I am having good luck (so far) with 117.5 instead. At least one other member with identical bike/mods went up to 125-127.5 mains, though.

                  For a long time, the stock 15 pilot was best as I had substantial richness issues, even with pods and pipe. More recently, after changing the top end, I have the more typical lean issues, and have upped the pilot to 17.5. If you are putting fuel screws out to 2 turns (1.9), you might have better luck with a bigger pilot jet.

                  For pods and pipe, the needle generally ends up in the 4th slot. I don't remember if that is 1 or 2 slots down from stock, i.e., whether the stock clip setting is the 2d or 3d slot.

                  A spread sheet or other app that took the stock jetting and crunched numbers based on mods would be pretty nice. It might need some tailoring across models, though. I have heard that some smaller GS bikes react differently to pods and in some cases have more airflow with the stock airbox. Dunno if that is accurate, but if you are building a reference for GS models, it's worth nailing that down.

                  Comment


                    #10
                    Originally posted by old_skool
                    I think you should re-post this in the tips/tricks, it won't get buried as fast, and easier to suggest to some where to look, and they will have all the other info in that section to wet their appetite as well.

                    Done.

                    BTW - if anyone has more details on the CV side of re-jetting, rock on in either thread. I am too dumb to understand butterflies and single idle mixture screws. Plus, the availability of Dynojet kits just drives me into a jealous rage.

                    Comment


                      #11
                      Originally posted by MisterCinders View Post
                      Done.

                      BTW - if anyone has more details on the CV side of re-jetting, rock on in either thread. I am too dumb to understand butterflies and single idle mixture screws. Plus, the availability of Dynojet kits just drives me into a jealous rage.
                      oh, hell yeah! i got your dinojet right here!

                      Comment


                        #12
                        The biggest advantage of the Dynojet kits for me was a time saver... They are virtually fit & forget in my experience with a bit of common sense.

                        If I had time to fart around & a Wide band kit etc I might be tempted to play with the stock ones.

                        You can also play with the size of the air jets too, in fact the Dynojet kit for the 8v CV carbs comes with a reducer bush for the fixed air jet in the mouth of the carb.
                        1980 GS1000G - Sold
                        1978 GS1000E - Finished!
                        1980 GS550E - Fixed & given to a friend
                        1983 GS750ES Special - Sold
                        2009 KLR 650 - Sold - gone to TX!
                        1982 GS1100G - Rebuilt and finished. - Sold
                        2009 TE610 - Dual Sporting around dreaming of Dakar..... - FOR SALE!

                        www.parasiticsanalytics.com

                        TWINPOT BRAKE UPGRADE LINKY: http://www.thegsresources.com/_forum...e-on-78-Skunk/

                        Comment


                          #13
                          Great write up, I've got the Disco Never Died 78 Vms as well, where'd you end up finding jets for your carbs since we're not using the Dyno? I've been having a hard time finding something off of Google that doesn't look mega sketchy.

                          Comment


                            #14
                            Originally posted by ilyena View Post
                            Great write up, I've got the Disco Never Died 78 Vms as well, where'd you end up finding jets for your carbs since we're not using the Dyno? I've been having a hard time finding something off of Google that doesn't look mega sketchy.
                            Check your Megawelcome for vendors

                            Z1 Enterprises

                            jetsrus.com

                            Googling "Mikuni VM carb jets" turned up 5 reputable vendors in the first 5 results
                            Last edited by Big T; 11-08-2012, 12:33 AM.
                            1978 GS 1000 (since new)
                            1979 GS 1000 (The Fridge, superbike replica project)
                            1978 GS 1000 (parts)
                            1981 GS 850 (anyone want a project?)
                            1981 GPZ 550 (backroad screamer)
                            1970 450 Mk IIID (THUMP!)
                            2007 DRz 400S
                            1999 ATK 490ES
                            1994 DR 350SES

                            Comment


                              #15
                              There's more to it. Some guys think richer is faster, some wouldn't know a proper running GS if they saw one, Some ride slow as molasses, some never back off the throttle, some are content with 20mpg and others demand perfection and will keep going with their tuning until they get it. Much like an oil, tire, or Harley vs real motorcycle thread, there is too much room for personal misinterpretation.
                              http://img.photobucket.com/albums/v5...tatesMap-1.jpg

                              Life is too short to ride an L.

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