running like crap after rebuild

[nick 94 blaster]

I put a new piston and rings in and ported and polished it.
it would spit and sputter and backfire a little bit and It will bog everytime u hit the gas. but after a little le bit of running it like that it will clean out and run good until you shut it off. thinking it might have to be rejeted after I ported it but I don't know

 

[Herpderplol]

What jet are you running?
Did you leak test...? <- DO IT!
What year quad?
What are all of your mods?

 

[nick 94 blaster]

No I didn't do a leak down test yet. It's a 94 bord 20 over wiseco prolite, bossen dual stage reeds, hot rod crank stock stoke, fmf fatty power core 2, moose carb spacer, k&n air filter

 

[3Blaster05]

Is there to much oil on the Filter? And do a leak test!

 

[Blaaster]

Did you heat cycle and re torque the head bolts.

With a forged piston you must adhere to a proper warm up.

A leak test is a must, and confirm the jetting with a plug chop.

 

[Larry's Shee]

I put a new piston and rings in and ported and polished it.
it would spit and sputter and backfire a little bit and It will bog everytime u hit the gas. but after a little le bit of running it like that it will clean out and run good until you shut it off. thinking it might have to be rejeted after I ported it but I don't know

Any time amount of air going in or out is changed you should at least check the jetting (plug chop/read)

If your "porting" is anything at all you are running lean now and chancing a meltdown soon.

Are reeds new or at least sealing good, good condition?

In addition to other suggestions clean carb, set float.

 

[nick 94 blaster]

Running a 270 jet and I did retorque the head and I don't have a leak down tester. Reed are like a Year old but there's nothing wrong with them. And I cleaned the carb

 

[Blaaster]

Depending on the severity of the porting you may need to increase the main over the following recommendations.

FMF = #260
Air filter = #270
Lid off = #290
32:1 = #300

Plug chop to confirm.


Before you make the plug chop run it is important that the float level is correct, the idle is set correctly and there are no air leaks in the system, otherwise the smoke ring may lie about the AFR.

WHEN ALL OF THE ABOVE ARE CORRECT PROCEED WITH THE FOLLOWING.

Warm up motor to operating temp.

Fit new B8ES plug, ride through the gears and hold WOT in 5th or 6th gear for 10 seconds, or as long as you can safely.

Switch off the motor and pull in the clutch, apply brakes to come to a stop quickly.

Take the plug out and replace the old one for the ride home.

Carefully cut the threaded end off the plug to expose the insulator.

There should be a smoke ring of a cardboard or biscuit colour around the insulator.

If it is non existant or a very light colour, you are lean and require a larger main jet.

If it is a lot darker you are rich and may go down a size in main.

I prefer to run a little on the darker side, I may loose a little power but it is worth it for the peace of mind that I won't need a rebuild so soon.

http://www.blasterforum.com/do-yourself-20/how-plug-chop-38674/

http://www.blasterforum.com/engine-13/plug-chop-how-vid-48226/

This is a good to go plug.

You have to get up a reasonable speed so that you can get the motor to pull strongly.

Then hold it Wide Open Throttle (WOT) for 10 secs or as long as you can.

The idea is not to get speed but to make it pull strong at full throttle to get onto the main jet circuit.

I find I can safely do it on a short run by applying the brakes some.

If you have not enough room you can use 4th or 5th gear with good results.