mpbanshee

There should be o-rings between the head pipes and the exhaust ports. I you dont have them, I would order some from LRD.

If you are dead on now, you will need to go up a size or two with the clamp-ons. However, 350 sounds way big for your mods. I would clean the carbs out really good, and also check for air leaks. Then do another chop with the 350's, and see if anything changes.

Take you time, don't get in a hurry. Put a light film of 2 stroke oil on the pistons and the cylinder walls before sliding them on. Make sure you gap the rings, and position them on the pistons correctly. Use new gaskets, and follow torque specs. Basically just follow the Clymer, and TAKE YOUR TIME!

Awwwwwwwww..... But we were having so much fun.

I use hose clamps. You can get them at pretty much any hardware store. For filters, try Dennis Kirk, Rocky Mouintain ATV, or any large parts supplier.

I'd go with like some 18:1 high compression pistons. Especially if you got some extensive port and flow work done on the heads. Get some heavier valve springs also...

If you have a bone stock quad, I doubt any jetting adjustments are necessary. You may just need to take off the carbs, and clean out all the jets and passages. Have you ridden Banshees, or any two strokes before this? Someone who is used to a 4 stroke may think a perfectly tuned banshee has a problem at low end...

If all you did was put on a timing plate for +4, and now it runs worse, something is wrong, and I doubt it is a jetting issue. I would pull the cover off, and check to make sure everything looks good. Maker sure the flywheel is on tight, and check the pick up coil gap. Gotta be something simple...

Sweet! Let us know how it works out.

May need a larger needle jet...

You may actually lose a little low end going from stockers to T-5's. HOWEVER, my advice would be to have .030" shaved off the stock head, and get an adjustable timing plate to bump the timing +4. Those two mods together shouldn't cost more that 100 bucks. That will drastically improve your low end, and you should still be able to run pump fuel.

I would think that if all you did was bump the timing +4 you should not have to rejet. I would run it at the throttle position where you are unsure for 10-15 seconds. Without letting off the throttle, kill it, pull the clutch and coast to a stop. Pull your plugs and check the color.

I would call Dynoport and see what jetting they reccomend for that setup with their pipe. I'm gonna guess you will need to start out with a 300, and work your way down till you get it right. Stock pilot and needle should be fine. Adjust the air screws until you get the best idle-1/8 throttle response.

Mine was hard as hell to push also. I cut a little off of the springs, and it made a world of difference.

No. Turning the air screw in richens the mixure of fuel to air. Turning it out leans out the fuel to air mixture. If you are less than a half turn out, you need a larger pilot. If you are more than two and a half turns out, you need a smaller pilot. Easy way to remember: rich"in" or lean "out"

I was a little confused by your post. Please explain in detail exactly what the problem is. What is the bike doing?

In order to get a good plug reading, you need to do a "plug chop", or a "hot kill" test. If you just ride around for a while, shut it off, and pull the plugs, you are not getting an accurate reading. Warm the bike up, take off and run through the gears up to 4th or 5th, hold it wide open for about 5 seconds, then immediately hit the kill switch, pull the clutch, and coast to a stop. Now pull the plugs and check the color. This will tell you if your main jet is rich or lean. Or, alot of people like the plug chop method. You can do a search and look into that as well. You should be pretty close. 280 may be slightly big for stock filter/airbox setup.

By no means am I knokcing the 2 into 1 pipe, but if you are gonna be flat tracking and dragging, that is probably not the best option. T-5's or FMF's would be my pick.

Are you planning on having the cylinders ported?

I was thinking that maybe CT ported the cylinders to have more top end power, which would take away from low-mid power. Porting for top end can create flat spots down low, but if it is sputtering and stuttering you may just have a rich jetting issue. If you think jetting is the issue, you need to go leaner on the needle. Raising the clip toward the top (blunt end) of the needle will make it leaner. Lowering the clip toward the bottom (pionty end) of the needle will richen the mixture. Try raising the clip and see if the flat spot goes away.

Sounds like a bad crank seal on the clutch side.

Is this a problem that just started, or has it always been like that? Could be any number of things. Are the cylinders stock? If not, who ported them, and what kind of porting? Stock carbs and needles? May just need a fatter needle.

Make sure your slides in the correct way (cutaway facing air filters). Also, the slides need to be slightly raised in order for the bike to idle. If your slides are the way down, it wont idle.

Pull the bowls off the bottom of the carbs. Spray carb cleaner and a little compressed air through the main jet. See if that helps.

They appear to be a bit rich. As long as the bike doesen't stutter or stumble when you are running wide open, I would leave it that way. Better to be on the safe side...