Thinking about ditching the pods

As much as I hate to give up, I think I may take my pods off and go back to the factory airbox. I just can't get rid of the surging on the highway. I ran the airbox until I rebuilt my motor.

Can anyone give my jetting recommendations with the airbox on? It's a 77 KZ1000 with MTC 1075 10.5:1 pistons, stage 1 ported head, V&H 4-1 with competition baffle, and VM28's with no accel pump.

I have 20 pilots, 127.5 mains, and the needle at full rich. I've done everything that I can think of to these carbs to fix the surge. Fuel level checked with clear tube. I've played with the mixture screws. Carbs are synced with mercury sticks. It runs perfect at every throttle position except cruising down the highway.

I thought the surging thing was an airflow imbalance problem of the air flowing into the carbs so jets and needles don't fix it. I remember reading the stock airbox is designed to equalize the airflow to the carbs which pods can't do.

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bountyhunter, I hope you are right because I put the airbox back on this afternoon. Back in the summer I had posted on here about my surging problem and LarryC thought the needle jets might have been 0-1, which is really lean. I knocked one out and they are 0-4. About the only richer needle jet that I can find on Ebay is 0-6 and they are expensive! I don't think that is enough of a change to mess with.

I had the needle at full rich with the pods. I'm guessing that it will run richer with the airbox, so I moved the clips to next to full richest groove. I hope that's close because it's a pain putting the carbs on with the airbox!

I left the 20 pilots and 127.5 mains in. Time will tell if they are right. It's 15 degrees here, so a test ride will have to wait.

Kraz1, that airbox is sweet! I don't have that kind of fabrication skills though.

Sudcos list of jet needles for the 26,28, and 29mm VM series just in case you didn't have it.
Copied andpasted from the downloaded catalog.

Jet Needle #5 Series (A)
Competition Racing Overall

1 #5D6 #5C4 #5C4
2 #5D120 #5D6 #5D6
3 #5C4 #5D5 #5D5
4 #5EJ13 #5D120 #5D120
5 #5J9 #5D1 #5F18
6 #5F18 #5F18 #5D1
7 #5DP7 #5F16 #5EJ13
8 #5FL14 #5FJ9 #5F3
9 #5F3 #5F3 #5EH7
10 #5EH7 #5EJ13 #5FJ9
11 #5FL #5EH7 #5DP
12 #5D5 #5DH21 #5FL14
13 #5E13 #5FL14 #5FL7
14 #5L1 #5FL7 #5E13
15 #5J6 #5E13 #5F16
16 #5D1 #5DP7 #5DH21
17 #5F9 #5J9 #5J9
18 #5F16 #5J6 #5J6
19 #5DH21 #5L1 #5L1
20 #5F12 #5F12 #5F12

Jet Needle #5 Series (
Competition Racing Overall

1 #5EP8 #5DP2 #5DP2
2 #5EJ11 #5DL13 #5DL13
3 #5EL9 #5EJ11 #5EJ11
4 #5EL9 #5EJ11 #5EJ11
5 #514 #5EP8 #5EP8
6 #5DL13 #5FL11 #5FL11
7 #5DP2 #514 #514

fordtruck wrote:

As much as I hate to give up, I think I may take my pods off and go back to the factory airbox. I just can't get rid of the surging on the highway. I ran the airbox until I rebuilt my motor.

Can anyone give my jetting recommendations with the airbox on? It's a 77 KZ1000 with MTC 1075 10.5:1 pistons, stage 1 ported head, V&H 4-1 with competition baffle, and VM28's with no accel pump.

I have 20 pilots, 127.5 mains, and the needle at full rich. I've done everything that I can think of to these carbs to fix the surge. Fuel level checked with clear tube. I've played with the mixture screws. Carbs are synced with mercury sticks. It runs perfect at every throttle position except cruising down the highway.

Congratulations ! Wait till you see how well, and precise your engine will run with the OEM airbox in place ! Why not start with baseline factory jetting ? Do you have a lot of engine mods ? In my jetting experiences with most street engines with only the addition of a 4-1 exhaust, all's that's needed is bumping the pilot jet one size, and shimming the needle .020". Sometimes you do need to bump the main one jet size if you do a lot of riding in the colder months..... Jet changes with an OEM airbox is very predictable and consistant as well ! Good luck !

heres what i do ...take em to a loud bar and then order drinks ...say "i have to go to bathroom" then give the bouncer 5 bucks to let me out the back....

screw those mods

fordtruck wrote:

As much as I hate to give up, I think I may take my pods off and go back to the factory airbox. I just can't get rid of the surging on the highway. I ran the airbox until I rebuilt my motor.

Can anyone give my jetting recommendations with the airbox on? It's a 77 KZ1000 with MTC 1075 10.5:1 pistons, stage 1 ported head, V&H 4-1 with competition baffle, and VM28's with no accel pump.

I have 20 pilots, 127.5 mains, and the needle at full rich. I've done everything that I can think of to these carbs to fix the surge. Fuel level checked with clear tube. I've played with the mixture screws. Carbs are synced with mercury sticks. It runs perfect at every throttle position except cruising down the highway.

i think a set of 29 smoothbores would not only cure that surge but top off the grunt you spent all that money inside the beast to achieve...

they wake up any bike and have none of the quirks the other kz carbs have...and work with pods like no ones buis..imo

I would love a set of 29 smoothbores. Unfortunately I blew my budget on the rebuild. I know that the port job probably isn't adding a whole lot of power with my current setup, especially since I'm still running the stock cams, but the potential is there when I do get better carbs and cams.

i have only had one true built motor and it was with 29's but i have had a few z-1,kz900,kz1000,with ignition,29, gutted headers with caps and no packing and 29's...the time will come and you will either find a set of oldies but goodies or save next yr for a set like omr did


the smoothies will do that thing justice and the cams in it will be fine imo....

my stock kz's with just 29's pods and pipes...pull hard

With your setup, I would use 22.5 pilot on the outside cylinders, then correctly tune the mixture screws with a colortune plug. You may or may not need to keep the larger pilots depending on breathing... All screw settings should fall within 2 turns of fully seated, else you will need to change pilot, or off-idle will be terrible/SURGE on that cylinder.

No colortune... turn the your mixture screws to add more fuel (whichever way depending on your carbs) until the engine stumbles/rpm drops noticably, then just turn them opposite about 1/3 turn or until smooth again.

On the outside cylinders, set the mix screws the same, except turn them in just slightly, till the engine smooths, but not quite as far as the inside cyls.

YOU WILL BE very surprised at how the mixture screw settings will ALL be very different per cylinder - this is because of the pods - and is less so with K&N's than the cheap pods.

This will cure your surging issue. Despite the fact that is is pulling primarily on the needle - as im sure some people will pipe up to say, this works.

OR - put the stock airbox back on! :laugh: and return to stock jetting - go from there.
You'll lose the better highway passing and some hard excell, but overall it will be smoother and cleaner sounding.

Best of luck!

Regarding the mixture screws, I tuned each one to give the highest rpm first, then tried richening each one the same amount. I could get to a point where the surging was pretty much eliminated but idle was terrible because it was so rich.

I'm going to try it with the airbox. If I lose too much power, then I will try the pods again with your method of tuning it. Funny thing is, by reading the sparkplugs it looked like the inner two cylinders were running leaner than the outer ones.