Strm Trpr

You need to do a compression test. Then a leak down test.

Start your own thread Haas. To the OP, check your floats and make sure the height is set properly.

I'm in to see how close sleeper06 is... OP, be sure to report back with your jetting specs.

What ^^^ said!! Get rid of that boost bootle and replace it with an OE cross-over tube. Do a search on here about boost bottles. Boost bottles are gimmicks that offer no performance benefit, are always in the way and they can crack the intakes. The sole purpose of a cross-over tube or boost bottle is to help equalize the volume the motor is drawing thru the carbs. A properly modded, sync'd and tuned Banshee does not need a cross-over of any kind. Read the following FAQ topic on Toomey's site. There is a "rich spot" between 4000 and 5000 rpm on the Banshee..... While it is true that it IS rich, the REASON it is rich needs more explaining. http://www.toomey.com/index.php?option=com_jefaq&view=faq&Itemid=8

^^^ trickedcarbine gave you an excellent staring point. Are you still running 25 pilots? If so, your pilot jet is your problem. Look how jetting works with throttle. Put the needle clip full rich, so 5th groove from the blunt end and work your way up. Also check the sync of your carbs and dial in idle. Run the exact jetting tricked suggested and report back. Eventually you'll need to do a quality plug chop. Get a quality compression tester, pull both plugs out and move spark plug boots away the best you can. Insert tester into a spark plug hole, hold WOT and kick the piss out of it until the needle stops climbing, write that number down. Rinse and repeat for other hooe. Finally, I'd do a leak down test for shits and giggles. Yeah, it's some work, but it will say a lot about the condition of your motor. http://bansheehq.com/forums/index.php?/topic/110585-leakdown-tester/

I really hope you mean 180*F because if you truly mean 180*C, that's 356*F... You need to do a leak down test and stop riding it NOW!! http://bansheehq.com/forums/index.php?/topic/110585-leakdown-tester/ BTW, ideal riding coolant temp is 180-200*F. At 220*F I'm looking for a strong head wind to ride into at a moderate pace to keep air flowing thru the rad.

^^^ is exactly why I said one side can be +.003" and the other side be -.003". There can be an accumulation of tolerances between all of the interfaces. Think about it. 1) The radial distance of the big end crank pin to the crank axis can be off a little. 2) Use a degree wheel and find out how many degrees the crank pins are off relative to one another. This will affect ignition timing. 3) The center to center rod lengths can be off a little. 4) And the compression height of the pistons can be off a little. 5) Then throw in the fact that the crank will move some when it's welded. Having a matched set of rods and pistons is crucial... It'll be interesting to see what happens when the OP swaps pistons and rechecks squish. Obviously the OP knows how to test squish. This is for those who may be following. Here's an excellent explaination of how to test squish. http://rb-designs.com/rb_designs_llc_017.htm

Redline 421 Serval on race gas = +5*. http://bansheehq.com/forums/index.php?/topic/178758-redline-421-race-gas-serval/

^^^ that's am excellent idea. If the difference remains the same, then the problem is on the crank/rod combo.

^^^ agreed

I guess anything is possible, but has anyone ever seen the deck height of a mono block be off by .006"?

If you're referring to my post, I started writing that post before everyone else answered. Isn't his cylinder a mono-block? I also left that info there for others to read during their searches for similar issues. Even if the total piston height between each cylinder is off by .006" can custom cut domes correct the issue to equalize squish?

Get a stock unmodded head, or use a thicker head gasket if one is available. Check squish using this method. http://rb-designs.com/rb_designs_llc_017.htm

I would contact Andy and talk to him. .006" is about as thin as two sheets of printer paper. I would imagine the difference is either in the domes or the crank/rod/piston tolerance stack. Either way, I'd imagine this can be corrected with domes to equal the same squish. One side of the crank/rod/piston assy can all be at the min tolerance and the other side can be at the max tolerance. -.003 one way and +.003 the other way. I'd pull the head and measure the piston's at TDC with a dial indicator. And if possible use a dial indicator to measure each piston's stroke.

2k ft ASL w/18cc domes on a fresh stock port motor should yield ~171psi.

Speaking of 4mil stk cyl, how do these pipes run on say a dune ported 4mil stk cyl?

What groove are the needle clips on? What are your current jets? What elevation and temp is your riding location? What octane fuel and what brand oil/ratio are you using? Have you done a compression test?

Why did you go back to stock? I want to go 4mil stk cyl dune port and I'm thinking +2 for duning. But I like to moto-x the dunes. Soon I will have a CRF450X for single track so the Banshee will just be a duner.

Change the gearing. Going down a tooth in front is like going up 3 teeth in the rear. Stock gearing is 14/41. Get a 13T front sprocket on there and that'll give you more torque/bottom-end. Careful now, she'll wanna come over on you if you thumb it too hard... LOL 30 pilots 260 main jets Airbox and lid still on? http://www.fmfracing.com/ridersupport/jettingcenter Get rid of that piece of shit boost bottle and get a proper OE cross-over tube. The intakes are prone to cracking where the boost bottle attaches.

300 mains 30 pilots http://www.fmfracing.com/ridersupport/jettingcenter

Top end is all main jet but the needle plays a role in it as well. Leave the needle in the middle clip. If anything, you might put the clip in the 2nd groove. That will lower the needle and lean out the mid range and top end a little.

Due to elevation and pod filters. 27.5 pilots 260 mains

^^^ Damn bro, thanks for stating that. I would've thought that was obvious.

Remove fuel tank. Pull plugs. Put it in gear and push it. The pistons will push all of the fuel out thru the spark plug holes like a geyser. Reassemble and run it.

Fireball makes a ton of parts for many vendors!!