gotta_goatsfast

I've been running my blue tank for two years now and it doesn't look bad to me. I got the Serval in and the pipes bolted up, with minor spacing/tweaking they fit great. I would rather have a big ass tank than push my quad back to camp. haha

Step back and work through this problem by first stating the obvious. If both cylinders have good compression and both cylinders show the same symptoms, then it is either a problem that BOTH carburetors are experienceing (bad fuel, poor fuel flow, jetting) or ignition (which is responsible for both cylinders). If both cylinders have good compression and one cylinder is acting up I would look into the carburetor on that cylinder or the plug/wires for that cylinder. Since it sounds like both cylinders are breaking up, and you have good compression (right?), then its most likely going to be ignition related (you might be getting a weak spark) or poor fuel flow...

Haha, you're probably a C class rider with cobbled up machines like I see around here. For the price I have in my ENTIRE suspension (about $1500 not $10000) I am pretty confident that I could run ten laps faster than you can. Why? I'm not going to get into a pissing match about who's a better rider, but I'm capable of pushing my machines limits and I'm willing to bet that my suspension (purchased used +2+1 arms, new swinger,PEPS shocks worked by Matt, YFZ brakes) will allow me to be more consistent and less fatigued toward the end of the race. Even if you have me in the first couple of laps, that bump steer and soft front end (probably soft stock rear shock?) banging on the ground is going to beat the shit out of you. It is then you start to stuggle and in mid air I am side by side smiling as I land comfortably and you brace yourself for the landing.... And if you think riding ATVs when you were young makes you quick and experienced, what do I get for riding an ATC 110 with NO suspension and rear only brakes keeping up with friends with 200-250cc 4 wheelers when I was a kid? Okay, done with the pissing match. Three things are obvious here... 1. You've never ridden a properly set up banshee and you are jealous of this (your loyalty to your suspension and anger show it) 2. You haven't quite grasped the concept of sarcasm 3. You really don't know Matt. He's very professional when it comes to his work and he is so cheap I question whether he makes much of a profit on any of it. So some of his posts are fuckin around, at least he's not asking where to get air filters....

I'd like to read up on the other side. I mean, he presented pictures of the rust and the pipes were only $200 shipped. It would be hard to imagine imaculate show chrome pipes for that price. lol

795 wiseco pistons are used with a 115mm rod. 513 for use with a 110mm rod. So, you can run a 4mil stroker (with 110mm rod) with 513 style piston or a stock stroke longrod with 795 pistons.

He should pick up some turbine core silencers. Find out what silencer he has right now. Even a powercore is pretty quiet with good packing.

I picked up a metaltech chromoly swingarm with skid mounts and round house carrier (I had the carrier already) for $400 from FAST. I wouldn't trust the cheapo ebay swing arms as they usually just use mild steel, have minimal bracing, use squared tubing instead of round tubing, and from the picture they look like the welder could have used a putty knife haha. Anyway, it might be cheap in the short run but if you abuse it and catch air... wouldn't it feel great if that twisted, broke, and shoved an axle up your asshole?

farmandsandtoys.com Give Jeff Wendorff a call. He'll get you all the parts you need.

Man you worry about loosing races, don't you. haha. As long as your bike is jetted correctly and everything is within spec (and you don't completely suck at racing) it shouldn't be a problem. BTW, FMFs are probably one of the quietest sounding exhaust you can find for the banshee. Its ashame he's going to stock pipes.

Usually CDIs either work flawlessly or do not work at all. Unless you can get another guy to let you borrow his CDI for testing purposes, I would rule out everything else first before purchasing a new CDI.

You can with a 110mm rod. But I advise against it because 1. Stock pistons are cast, not forged. The piston speed will be increased because of the longer stroke and it will most likely cause a failure. 2. 115mm rod provides a more reliable rod angle vs. a 110mm rod. Using a stock cast piston with the longer stroke can cause great wear and stress on a cast piston's skirt.

General consensus is that 35mm PWKs work best for all around 421 cubs while something larger like a 39 is used for guys looking to squeeze a little more. In your case, however, I would consider 33mm carbs to match the pipe you plan on running. It kind of sucks you chose the cub for the riding you do when there are a lot of new configurations out there by CP industries that would have suited your riding style better. But, I've heard you can dumb a cub down a little and make it slightly less terrible in the trails haha. Anyway, 33 or 35 Keihins would work best for you (there's a TON of support from other members with these carbs and 421 cubs)

They work really well with a stroker crankshaft...

Looking good man! Just don't burn yourself out.

Start with 162 main, 50 pilot, CEL needle middle clip and break it in. Then plug chop your way to the perfect jetting (my guess is 155-160 main and 48 pilot). My serval with 35s seems to really enjoy 158s... I could probably go a little lower but I like it to be slightly fat for reliability and such.

What you want to do is seat the rings. You do this by constantly varying throttle/load. First start I idle the engine around 2000rpm until water temp exceeds 120 degrees. Then I vary the rpm up to 2800ish and fall back to 2000rpm. Once you hit 150-160 shut it down and wait until it cools to under 100 degrees. Fire it up and repeat until you reach 160 or so. You can sync the carbs and other bullshit while monitering the temp. Once temp has reached 160 go ahead and hop on. Ease the throttle and get the quad moving. This is a very important part. You want both positive and negative pressure on the rings to seat them properly. If you've ever ridden an MX track, the first time you ride a new track you go around fairly easy to learn the track, correct? This is the type of riding style you want. Brief accel. and constantly changing speeds, gears, rpm. Remember to err on the rich side as to not run a fresh motor lean. IMO its best to break in a motor with as few cool downs as possible. Especially with forged pistons. All your components are machined so that the proper clearances are obtained with the engine warm (they're loose when its cold). When you idle your bike and then shut it down and repeat three or four times like I've seen some folks do, this is actually wearing and seating your rings to your cylinder in an unusual way. You want your rings to seat (which results in sealing the combustion chamber) at operating tempurature.

Look man we're trying to help you but you're not helping us (to help YOU). Maybe your guy can help you out since he built your motor and stuff.

Bearings need lubrication to keep friction to a minimum and heat down. Without it, you probably toasted your bearings and bushings. This would explain the noise and the lurching forward (bearing does not spin freely anymore). If it was a shift fork trying to engage the gear, you would hear the cogs grinding and banging trying to engage.

Yea, you sound really stupid. I suggest you go to the doctor.

(drum roll) and....

Okay, I'm assuming you haven't "moded pretty much everything you can do" if you can't figure out what jets you have in your carburetors. I suggest digging into your carbs and find out what jets are installed. Your original post sounds like a lean condition whether it be from insufficient jetting or an air leak. Boost bottles, for instance, are a notorious for cracking your intakes and causing a fatal air leak (and they really don't do anything for performance btw). Anyways, your next post should include exactly what has been done to your banshee motor wise, what the air temp is, what the elevation you ride in is, the current jets, and that you have confirmed it passed a leak down test. There is plenty of information on BHQ already explaining how to check your jets and how to perform a leakdown test. Browse through the stickies at the top of each section.

If you are serious about building your engine, give some of our sponsors a call. They will point you to a port job that reflects your riding style and goals best. A trail port for a 4mm stroker is going to have correct port timings for a 58mm stroke.... and low end-mid range power. This is why I recommended a low-mid pipe. If you want more mid range and top end you might consider a "play" type of port job. Builders usually call them hot MX, MX hardcore, play/dune, ect. The person who you choose to port your cylinders will most likely base their porting around your current set up, including the T5 pipes. This would be a good compromise for trailing and dragging (but it won't be the "best" at any one riding style, either). Then there is the dune/drag type of porting that narrows the powerband to a hard hitting top end. This will sacrifice a lot of ridability but in a straight line there's not many a 4 stroke that will keep up. Just don't play with them on their home court or you'll find yourself struggling below the powerband or in a tree (I'm of course talking about trails and such). Jeff at FAST racing has treated me great, and there are plenty of others who come highly recommended.

If you're running a trail port then the T-5s wouldn't be a good match. Check out pro-circuit pipes.

I'm curious as to why you want to leave the cylinder ports completely stock? There are minimal gains going up in displacement through a bore without adjusting the airflow to match it. The 58mm stroke isn't going to be very exciting when the ports are designed for a 54mm stroke. A 115mm rod will provide minimal if noticable-at-all gains over a 110mm rod, but is smart to do for reliability and stability in the engine. The banshee is almost limitless, so don't limit yourself here. A good woods/MX port job on stock cylinders with a stock crank and stock bore will be a more exciting ride and make more power everywhere than all three of the previous mentioned mods combined (on stock port timings of course). A great budget power build is to purchase a 58mm crank with 115mm rods and have the stock cylinders ported to match this. You can damn near pull a stump out with it... okay maybe that's a little over the top haha.

I assumed you had yours tuned. If this is true, going down in size will lean out your motor. If not, do a plug chop and start tuning. Also, just because his pulls real hard does not mean its boarderline lean. Unfortunatly rich symptoms are usually easier and make themselves obvious. A lean engine will rev high and be "zingy". So, I'm not ready to rule out that its not on the lean side.