Pods Vs. Stock Air Box

[RocketReady]

I would like to replace my stock airbox with pod filters. First of all, should I even be thinking of doing this? I understand that my stock carbs need the vacuum created by the airbox to function properly. My airbox is not in the best of shape, I am pretty sure it is not functioning well anyway. If I do go to pod filters what carb mods will I need to do?

[Steve]

Sure think about it all you want. But, while you are thinking about it, be sure to also think about all the details about the change.

If you go with quality filters (K&N, etc.), they will cost more, but you only buy them once, then clean them.
Still decent, but lesser-quality filters (Emgo, etc.) are less expensive, but are not cleanable, so when they get too dirty, you have to replace them.
Either way, you will have to re-jet the carbs to compensate. What jets you will need will depend a bit on which pods you get. With your VM carbs, you at least have the advantage of adjustable needles, but you will still need different main jets.

My suggestion is that, unless you are going for maximum power or a particular 'look', stick with the stock airbox.

.

[coltrain]

You will need to put the needles in the 5th position with the clip. Around 127.5 -130 main jets. Stick with the stock pilots and 1.5-2 turns out on the fuel screws.

Do you have an aftermarket exhaust? 4into1? That piece of info is needed for the above jetting. I went through this with my bike and Im' using K&Ns

[TheCafeKid]

You will need to put the needles in the 5th position with the clip. Around 127.5 -130 main jets. Stick with the stock pilots and 1.5-2 turns out on the fuel screws.

Do you have an aftermarket exhaust? 4into1? That piece of info is needed for the above jetting. I went through this with my bike and Im' using K&Ns

1.5 out on the FUEL screws was WAYY too rich on my 77 750 with 130 mains and the needle in the FOURTH position....

[RocketReady]

Will also be using V&H 4to1 exhaust recently purchased. Am looking to produce max power and have the "look" I want. Plan on high quality cleanable pods.

[muskies666]

i am currently tuning the same setup on the same bike, vance & hines 4-1 and k&n pods, and i think im close... the previous owner had the bike jetted for the kerker that was on it. i backed the needles out one notch, they were all the way in, and it is running well after some pilot adjustments. but i have heard a rumor about adjusting the outside carbs slightly different than the inner two because the outer ones get more turbulent air. i was wondering if anyone else has heard this. i dont know much about bikes, and none of the shops in my area will work on my bike. even the suzuki dealers.

thanks a ton, this site has been super helpful.

[doctorgonzo]

Will also be using V&H 4to1 exhaust recently purchased. Am looking to produce max power and have the "look" I want. Plan on high quality cleanable pods.

I have pods and 4 into 1, buy a dynojet kit, don't try and jet it yourself. Even with a kit it will likely require multiple puling off of the carbs to tweak them before you get it right. The bike will also become slightly less "street friendly". You will lose some bottom end torque making it not run as strong in the low RPM ranges, and mine tends to carbon up the plugs if you are doing a lot of idling/stop and go in traffic. That being said, the weight loss from the pipe makes the bike handle much better and from mid RPM (say 5000 to 6000) on it runs like a bat out of hell.

[RocketReady]

I got the bike to run which is a big big step forward. I have only run it a bit because its really lean, (lotsa carbon on the plugs). Checked dynojets website. Does not seem to be a dynojet kit available for my bike. Will have to rely on the great input/wisdom of you all when doing the tuning. First will get my ducks in a row by obtaining a quality O-ring kit. And everything I need to properly clean the carbs. Will clean the carbs and install whatever main jets, etc. that you guys suggest. Thanks.

[doctorgonzo]

I got the bike to run which is a big big step forward. I have only run it a bit because its really lean, (lotsa carbon on the plugs). Checked dynojets website. Does not seem to be a dynojet kit available for my bike. Will have to rely on the great input/wisdom of you all when doing the tuning. First will get my ducks in a row by obtaining a quality O-ring kit. And everything I need to properly clean the carbs. Will clean the carbs and install whatever main jets, etc. that you guys suggest. Thanks.

Carboned up plugs would be rich not lean. What kind of bike is it?

[hampshirehog]

Best is to tune it stage by stage. I'd drop the clip on the needle to No 4 as a temporary thing then tune in the main jet. You're gonna need something between 130 and 140, may be a tad either side and it's trial and error, to suit your set up. Do a plug chop on WOT or pull 3 plug leads and use a colourtune on WOT.

Once you've settled on the mains tune in your needle. It's gonna be 4 or 5. Plug chop again at half throttle.

Tuning the slow run - I'd leave standard jets and try running with the airscrew just 1 turn out before messing with the fuel screw. I like Colourtune but if you've a good ear the highest revs method is easy as well.

You'll need to synchronise your carbs as you go - not too critical at wider throttle openings but essential for the pilot circuit.

[Steve Wade]

Carb mods

I am new to the GS range - I took the stock filter box off my GS 750 and fitted pod filters and encountered all sorts of issues - basically the bike ran ok at no load conditions and revved fine - but on the road as soon as I went over a quarter throttle the engine died - got some great advice from NRP Carb in Manchester UK - they recommended fitting an air restrictor kit to the main jet system - cost around GBP17 - seems by removing the stock set up you are feeding to much air into the carb and upsetting the mixture big time - this kit fits a smaller restrictor in each carb - its a fairly simple job - the kit comes with a tap that you thread the main jet feed on the airbox side of each carb - need to take your time as I recall they are handed - full instructions come with the kit - I also took took the main jets up around 4 sizes as well - now starts on the button and runs sweet pulling strong through the range - plugs are a nice deep tan after a long run - take your time - its a real pain taking the carbs on and off time after time but well worth it in the end - also worth double checking the float heights are correct -

[Mysuzyq]

But, isn't that kinda defeating the purpose of going with pods....to increase the amount of air available to the carb. Restricting it again, to approximate the flow with an airbox wouldn't have much performace benefit, if any?
Better to get the jetting right, via a Dynojet kit and follow the instructions so that the amount of fuel is also proportionally increased, I would think.

Tony.

[doctorgonzo]

But, isn't that kinda defeating the purpose of going with pods....to increase the amount of air available to the carb. Restricting it again, to approximate the flow with an airbox wouldn't have much performace benefit, if any?
Better to get the jetting right, via a Dynojet kit and follow the instructions so that the amount of fuel is also proportionally increased, I would think.

Tony.

My dynojet kit came with little restricters, but I took them out fighting a rich condition.