• Required reading for all forum users!!!

    Welcome!
    Register to access the full functionality of the GSResources forum. Until you register and activate your account you will not have full forum access, nor will you be able to post or reply to messages.

    A note to new registrants...
    All new forum registrations must be activated via email before you have full access to the forum.

    A Special Note about Email accounts!
    DO NOT SIGN UP USING hotmail, outlook, gmx, sbcglobal, att, bellsouth or email.com. They delete our forum signup emails.

    A note to old forum members...
    I receive numerous requests from people who can no longer log in because their accounts were deleted. As mentioned in the forum FAQ, user accounts are deleted if you haven't logged in for the past 6 months. If you can't log in, then create a new forum account. If you don't get an error message, then check your email account for an activation message. If you get a message stating that the email address is already in use, then your account still exists so follow the instructions in the forum FAQ for resetting your password.

    Have you forgotten your password or have a new email address? Then read the forum FAQ for details on how to reset it.

    Any email requests for "can't log in anymore" problems or "lost my password" problems will be deleted. Read the forum FAQ and follow the instructions there - that's what we have one for...

  • Returning Visitors

    If you are a returning visitor who never received your confirmation email, then odds are your email provider is blockinig emails from our server. The only thing that can be done to get around this is you will have to try creating another forum account using an email address from another domain.

    If you are a returning visitor to the forum and can't log in using your old forum name and password but used to be able to then chances are your account is deleted. Purges of the databases are done regularly. You will have to create a new forum account and you should be all set.

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

  • Thread starter Thread starter MisterCinders
  • Start date Start date
M

MisterCinders

Guest
Cross-posting this here from the thread in our Carb/Exhaust Forum

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.
 
I put a Marshall 4-1 on my GS650G and bumped the jets up. I got worse mileage and that's about it. Went back to stock jets and it's fine. It seems my pipe was engineered to work with stock jets according to Marshall tech support and doesn't require modifications.

If you buy from a reputable company instead of MAC you should get proper tech support. If the pipe is modified, unknown, or a hybrid of different parts you need to go through the tuning process. Spend the money for a good pipe from someone who knows what they are doing, or at least get a pipe with known characteristics used by others.

This means plug chops, a selection of parts, and plenty of time. Posting on the GSR expecting someone to solve your problem on the internet will not cut it.

A new pipe has a minimal effect on carbs whereas pods change everything. Those who proudly state how easy it is to get the carbs off for adjustments are missing the point that we with airboxes generally don't remove our carbs except to clean them when we get the bike.

The true diehards use oxygen sensors, dynometers, stop watches, thermostats, hydrometers, altimeters, and four leaf clovers. They also pay a lot of money for all this. And are rewarded with 5-8% power improvements and 10% worse mileage.
 
In the real world of motoring, one either gets tuned for economy or power. Very seldom both. You have to draw a line of compromise on the issue, the old adage of if it isn't broke don't fix it is very true.
 
Back
Top