Needles Shimmed, Snorkel NOT Removed

[sreisig1]

Hey Guys,

Have a 2010 Ninja 250, shimmed with 2 washers on the needles. Guy who did it for me didn't remove the snorkel. Seems to be riding fine, but should I remove the snorkel? Will there be a benefit or will I have to resync carbs?

Have a Two Bros slip on...

Also debating on getting pods installed and removing the stock airbox and having it rejetted.

What are your thoughts on pods vs just leaving the stock air box in?

[RacinNinja]

Pods are good for making noise.

Leave the stock airbox.

You can remove the snorkel if you want. If you do, it will require a re-jet and tune.

[jkv45]

If it feels good now I would leave it in. Removing the snorkel will flatten it out a bit on the bottom and midrange, and require a jetting correction to get back some of it.

We have 2 Ninjas - one with the airbox and one with pods (both rejetted). My son likes the one with pods better. The intake noise is obnoxious. Both have stock pipes and you can hear the pod bike coming a mile away (literally). It's rarely under 10,000.

Pods may show a small amount of power gain at WOT and max revs, but chances are you will lose some in the range where you are riding most of the time.

[HoneyBadgerRy]

I have a bike with pods, and I didn't notice any loss in the midrange, and I think I noticed some power gained in the higher rpm range, however its hard to tell what is a power gain and what is an illusion due to induction noise.

I know pods rob power on bikes all the time, because air boxes are important. However, I also believe the ninja 250 was a very restrictive intake. The only way to find out is to line up a stock bike and a bike with pods side by side.

I do know that heavily modified bikes with pods make about the same amount of power as ones with stock airboxes on a dyno, but wide open dyno numbers aren't everything, and every dyno is different.

[Ghostt]

Most everyone here's knows my position on pods for the Ninjette, leave the stock airbox, get a better air filter like K&N etc....

But for those that don't know my stand, here it is again,

I would highly recommend that you DO NOT REMOVE THE AIR BOX, the carburetors on the bike are CV type and need to box to function properly, buy a K&N that fits the OEM airbox(K&N KA-2508 Kawasaki High Performance Replacement Air Filter by K&N Amazon.com: K&N KA-2508 Kawasaki High Performance Replacement Air Filter: Automotive Amazon.com: K&N KA-2508 Kawasaki High Performance Replacement Air Filter: Automotive ) that's the short version.

Long boring but important answer, CV carbs stands for "constant velocity". The function of the carbs is dependent on having a calm reservoir (airbox) from which to intake air at said constant velocity. Pods draw from the turbulent, unpredictable air swirling past them as you ride, which is anything but constant. Other carbs work fine with pods. CV's = no bueno, save yourself the headaches.

Now onto jetting, first you need to tune the idle mixture screws first, I recommend 3 full turns out from bottom as a good starting point, then fine tune them afterwards. As far as buying a jet kit, I personally don't have one on either my 250, or 500 ninjas. I did got up one size on my main jets, due to they are lean from the factory, and shimmed the main needles with a small washer.

[Flying]

Removing the snorkel won't do much. Pods won't do much without a proper full-exhaust (slip-ons are just noisy), and will require a rejet.

Keep it as close to stock as possible or go all the way.

Although, that's a bit of a lie. The stock airbox isn't actually a restriction. The stock intake flows as well as pods (arguably better, because plenum) as long as you replace the filter.
It is a pain in the ass though, I hate having to pull down the rear fender.

[sreisig1]

Thank you everyone for your responses.

Ok, I'm going to leave the stock airbox then. Already have the K&N filter installed as well.

So Ill still need to rejet after removing the snorkel, even though the bike was already rejetted 1 size, shimmed with 2 washers and 3 turns on the POS screws.

Removing the snorkel would change the airflow THAT much to have to re-tune everything? Just curious.

[Ghostt]

IMHO your fine, maybe just tune pilot needle screws.

Take for a test ride, and see. To be honest without the use of an exhaust gas analyzer your just making a best guess about jetting. Try the jetting database located here on the forum. Good thing with owning such a popular bike is someone out there has done the hard work already, and made a post about it.

Here's my write-up on the subject of tuning the pilot circuit.

Your initial setting should be 3 full turns out from the bottom, remember just slightly tighten them, don't go all Conan on them.



Then warm it up, slowly turn 1 side pilot screw in until the rpms drop, then back out till RPM's peak (and no further)* Twist throttle...see how it reacts...tweak to taste.
Repeat on other side... test ride. You're looking for best throttle response and transition from just cracked to 1/4 throttle opening or so.*

Thats a quickie, 10 cent tutorial on setting pilot screws.**

[jkv45]

Originally Posted by sreisig1

Thank you everyone for your responses.

Ok, I'm going to leave the stock airbox then. Already have the K&N filter installed as well.

So Ill still need to rejet after removing the snorkel, even though the bike was already rejetted 1 size, shimmed with 2 washers and 3 turns on the POS screws.

Removing the snorkel would change the airflow THAT much to have to re-tune everything? Just curious.

Removing the snorkel is a significant change. It would run, but to have it run properly you would need to make at least some adjustments.

You could try it and see how it feels. It will be louder, so don't be fooled into thinking it's faster...

[headshrink]

Originally Posted by jkv45

... Removing the snorkel will flatten it out a bit on the bottom and midrange, and require a jetting correction to get back some of it....

Since this is the spot I'm trying to work out right now with my jet kit, I might just put that snorkel back in. What a pain that will be, but no more than pulling the carbs 20X.