J-Madd

So the plugs were just fouled then. I didn't mention to change plugs, I figured fresh ones would be installed with the rebuild. As far as idleing, that's easy. You can loosen the screw that holds the cable to the thumb throttle assembly to tighten it (the cable), and increase the idle. The TORS is probably OK if it runs good. I'd unplug it anyway. Its the little black box mounted to the frame under the left side of the gas tank. Just unplug the wires. You can also idle it at the carbs. If they're stock, there is a big knob on top of each carb by the cable. You have to turn both of them the same amount of turns and keep your carbs in sync.

What was yours and Michael's gearing? I'd like to run mine there and get a time slip. I can launch mine on pavement and lay on the freakin back and it still won't raise the front end. It just spins for about 20 ft then hooks. I had it lowered in the back, but I've raised it back up to stock to try to get some weight transfer for traction. BTW there were 3 of us on Banshees at Sand Creek Saturday. Not a soul there, though. We might go back this Sunday. I know my Cub Banshee sucks to ride there, so I take my YFZ too.

I thought about that too, but with 20cc domes.............................. :shoothead: wait a minute you're right. I was thinking the 20 cc was around 150 psi, but that's the 21 cc. Even with stock timing you're probably gonna need to up the octane a little. Mine stock jugs with 20 cc domes had damn near 180 psi at 300 ft elevation. Good call.

Oil mixture shouldn't cause those symptoms. Here's a list of things to check or do: - un plug the TORS - see if the choke tube is in place (everybody's forgot that at 1 time or another..even mechanics don't put them back on sometimes) - Make sure both carb tops are screwed down good. If one is loose, it'll lean out and rev up. - Make sure both carbs are getting fuel and see if the pilots might be clogged. Your jetting shouldn't be the issue if it ran fine before the rebuild, and you didn't get new pipes or filter. If you were stock before, and added those, then you would obviously require jetting changes. Boreing it and adding the head wouldn't affect jetting.

So both sides are blowing out exhaust, but one is hot and not smoking? I'd check too see if the carbs are in sync and check the compression in both cylinders.

FYI: I checked my pilots and they were 48's. BTW I bumped them up to 52's. From what everyone is saying 48's are a little lean for 300 ft and even 90+ degrees. I also dropped my mains to 165. Hope this helps. I'd be interested to see what your jetting is when ya get it dialed in. I know mine still needs some fine tuning.

I have your exact setup. I'm at about 300 ft elevation. Not sure which needles, but I running the clip in the middle, 45 pilots (I think), and 170 mains. It's rich as hell (oil buildup on ends of silencers) and needs some fine tuning, but I've yet to foul a plug and it screams. You'd obviously have to go leaner with your elevation. I'm gonna see for sure which pilots I've got and probably go down to 165 mains until it cools off outside. Edit: I'm running a Noss head w/20 cc domes and 112 octane gas.

Yeah...I've got a stock stroke 68mm cub, and I even forgot to list a few things. LOL :yelrotflmao: . Hell I've probably got 3 grand in mine, I guess. I don't even keep up with the money I put in these things anymore.

Here's my best guess: Cylinders: $850.00 Crank: Probably around $600 or so, just guessing. Porting: ????????? Cool Head w/ Big Bore Domes: $350.00 Pistons: $300.00? Bigger Carbs: $350.00 Seals, Gaskets, etc.: ??????? It's gonna run ya close to $2000.00 I'd think

I wouldn't think the reeds would EVER close as long as the engine is running. Wouldn't the air/fuel mix be traveling into the cylinders all the time anyway, just more so on the down stroke? The plugs also fire at BDC as well as TDC, wouldn't that clear the cylinder of any fuel anyway....there wouldn't be anything left to travel backwards into the carbs. Just my theory.

I just got my 68 mm cub stock stroke engine back from him TODAY . He trued and welded my crank and had to send my Cubs to get re plated. I think a clean up port too. The bad thing is that today is my freakin aniversary so I probably won't get to put it together today

:baseball_bat: WHOA!! I'm surprised it'll even try to start with compression that low. Did you hold the throttle wide open and kick it until the gauge stopped moving? Time for a rebuild. Ya beat me to it!

Sputtering through about 3rd gear, until it cleans out. I fixed a guy's Banshee this weekend that had the slides in wrong. It took 10 mins and he paid me $40. I immediately knew what was wrong by the symptoms, having done the same thing myself a few years ago.

Tell him to shave it 20 thousandths IMO. That'll put it close to 150 psi.

Checked choke tube? I see you have the TORS eliminator kit, but is the black box unplugged ?(under the left side of the gas tank)

While started, does it try to roll very fast with the clutch in. Its pretty common to no be able to roll one while in gear w/clutch in, or for it to want to roll a little bit while in gear. It takes a few rotations of the crankshaft (tires) to get the clutch to working. But......just tighten the cable. That should fix it. Don't get it too tight or it'll slip and you'll fry it.

I agree. If you don't see any obvious damage when you take it apart, it's probably ok.

I've ran the big jets since 2003. I think I ran 350s or so in it last summer. With different stock carbs. These are 2006 stock carbs. ...........I know, I've never seen anyone suggest this size jets. My pluts were not bright white with the 350s. but were very light tan. Edit: maybe its this part of country. I use way bigger jets in my YFZ than the forum recommends. My buddies got his even richer..............178 main, 48 pilot, needle in the middle. Its got a HMF full system, K&N, and Hot Cams. His runs great

I left the jetting the same. Not a huge difference. Lost lots of low end and gained a little through the midrange and upper RPMs. The power comes on different and its hard to know when to shift b/c it sounds the same from the second ya pop the clutch in 2nd all the way through 6th.

My basically stock Banshee w/T5s, k&N, no lid at 300 ft elev, 90 degrees F runs a stock pilot and 370 mains, needle in middle. Plugs were a little too white @WOT with 350s, so I jumped up to 370s. Every one is different, but I've always had to run pretty big jets w/T5s. On my motor, I'd be scared to death to go below 330, even at 90 degrees.

Until I get my Cub motor back for my new Banshee; I'd though I'd try my CPIs on my old one. Currently running T5s, K&N, no lid, shaved head .0020, 370 mains, 60 over bored (not because I wanted to! )stock pilots, stock needle in middle, stock timiing. This bitch screams to be basically a stock motor. It'll beat my YFZ, all my buddies' other piped and jetted, timing advanced Banshees, from start to finish. It even gets the holeshot on the 4 strokes on dirt. What, if any jetting changes from the pipe exchange?

Make sure the slides are in the correct carbs....cut away of the slide toward the airbox.. They will fit backwards (right slide in left carb, etc.). The motor will have symptoms just like you described. It was my first mistake as a new Banshee owner, but they were in wrong when I got it, so I put them back in wrong after I re-jetted.

I'm putting one back together that only has about 3 rides on the gaskets before we f'ed it up (long story) and I was planning on re-using the gaskets. Hell they look like new. I can afford gaskets, but the buddy that f'ed it up and is going to pay to fix it and is limited on what he can spend. There wasn't even a full coating of carbon on top of the pistons. Ya' think it's risky re-using those gaskets?

What about Maxxis 4-Snows? There was a YFZ kicking ass with those on grass last weekend where I rode. I didn't get to race him, though, but on my YFZ with stock tires I was not beating a 450R near as bad as the guy with the 4 Snows was (he said.....I didn't see them race.)

Increases compression for more bottom end torque/no