blowit

If it runs fine once warmed up, I would highly suspect you are not operating the choke properly or it is not working right. The choke has two positions and many times not pulled out all the way. I would also advise that you screw the air screws (brass screw, filter size, bottom of bell) in about .5-1.0 turns. I highly doubt you have an electrical or major jetting issue. Sounds like it needs more fuel when cold. Brandon Mull Engineering

up-zeez

We need to grab up some more cores to keep in stock for various head setups. If you have some stock Banshee heads, please shoot us a PM with pics and price. Willing to buy individual head but rather buy several in a lot. Need pics of top and bottom. Minor damage may be accepted but not looking to buy junk heads. thanks brandon mull engineering

1. I agree with Zilla, the fact that your "water" heated up faster proves it makes a better thermal conductor than "coolant"(which Ethelyne Glycol and water). Look up the properties for Ethelyne Glycol, then water. Not only is the thermal conductivity better, but the thermal mass will be higher so you can get more btus out of that engine with water. Remember that a fluid must heat up if you want it to carry that heat out of the engine. 2. There is nothing in a water and EG solution that will dissolve Aluminum. However, coolant will turn acidic over time from a "lack of maintenance". As well, straight distilled water with no EG WILL eat Aluminum. It will actually eat about anything due to its charge. That is why you put EG in the fluid to stablize it. In short, with proper maintenance, a "good" billet impeller should last you 20yrs...

1. Flowing fluid too fast through an exchanger is not really a problem of not cooling the engine, it is an issue of efficiency. If that fluid needs to make 3 trips through the exchanger to get it cooled because it is moving too fast, that is an efficiency issue. AKA, wasted power. This means claims of "mega, super, outstanding, stellar, superior" flow will net you nothing. The key is matching the flow rate with the power input into the fluid and the exchange rate (delta T) across the exchanger to maximize cooling in one pass. I do firmly agree with thermostats though. They are mostly used to get an engine up to temp quicker, and help maintain a "constant" temperature in the system which is most important for bearings, seals, and gaskets as well as pistons. We all know what can happen when you flog a cold engine.... 2. Maintaining pressure in a cooling system is paramount and the reason we focused more on that than anything else with out pumps. Your coolant system is pressurized for one reason, to "increase" the boiling point of the fluid. There are always hot spots in an engine that will locally boil water if proper system pressure is not maintained. 3. I have worked closely with a guy in the middle east regarding cooling a big cub engine. It is BIG problem because people seem to ignore cooling when they build that 150hp Banshee. A engine is VERY inefficient with chemical to mechanical transfer and about 60% of the fuel you use goes into heat in the air! This just means you need to be thinking about cooling with every build. Couple that with extreme ambient temperatures and the problem becomes worse. An exchanger is ALL about the differential temperatures of the fluid in it, and air flowing over it. The higher that delta, the more power you can dissipate. As ambient goes up, power dissipation goes down. Just to run in 130*F ambient, you need to roughly double the cooling system capacity for a STOCK engine! Also, as some posters mentioned, water is really your friend, NOT antifreeze. However, antifreeze brings water stabilizer, lubrication, and boil over to the party. I agree with the 3:1 blend but water is not really the "best" coolant, it just has well rounded properties that suit it to this job. It is all about the thermal transfer coefficient of the fluid. The higher the better. There are certainly fluids that are better but have you have to have something inert, stable, cheap, etc. Just stirring the pot! Brandon Mull Engineering

No, radial movement of the LH piston should not cause what you are describing. I would recommend swapping the plug cab L ro R to be sure but if you are confident this is not electrical, that pretty much leaves carbs. When you sense the L side pulling back, pull the choke and see if it comes back. If it does, you know you need more fuel on the L. Check carb balance (slides), and carb clean. Usually the pilot jet is plugged. Brandon Mull Engineering

This is where people either waste their money or waste a good bore, or blame casted pistons because your bore clearance is not right. The ONLY way to verify a bore is with a bore gauge. Having it bored for the hell of it is not advisable. True that damage you can feel may warrant a bore, but just because it is smooth does NOT mean the bore is good and it is also possible and likely that the bore is perfect. I recently inspected an ORIGINAL 1987 Banshee engine for a family member. I was shocked that she was well within spec. I told him to put it together and ride it a few years and go from there. There is a reason there are dimensions in the book. Looking at a bore just does not tell the story. Regarding cast pistons, they get a bad rap and if you read back to some of my previous content years ago, I explained that casted or hypereutectic pistons DO have their place and WILL last longer than forged pistons compared side by side. The casted piston contains much more Silicon and is a harder alloy that resists wear and thermal expansion. They also expand more uniform thus require much less bore clearance. Don't sell casted pistons short. Forged do have their place but 90% of Banshee engines will do great with cast pistons. Brandon Mull Engineering

Tricked, the main complaint we have seen with the lighter detent spring on our stars is jumping gears on rough terrain. Some indicated that when landing a jump, they would tend to downshift when hitting the ground.

Good morning guys, I figured I would try to answer any questions on this kit. The roller bearing that we use is a shielded type that helps prevent any debris from getting in the bearing. There is very minimal radial load or rpm on thiss bearing so IMO, anything short of lifetime life, I would be suspecting that either something got in the bearing or possibly was assembled wrong. The attachment components use mechanical locking to prevent them from coming loose but probably a good idea to check on everything whenever thee clutch cover is off. We did quite a few tests comparing the stock and roller bearing detents and you could certainly feel the difference. Smoothness was most notable. The shields on the bearing would also work to contain any debris from the bearing but in most any case, the bearing should just lock up and be harder to shift rather than exploding. Remember that it is not constantly spinning, just glides over the star. Brandon Mull Engineering

Outstanding There are actually a couple great points on both sides of the fence here. The OP was able to successfully repair the said bike with proper grounding. Hoppedup above has indicated the frame does not need grounded. Both are actually right. Technically the engine has a ground wire, which is black, is 18ga IIRC, and is mounted on one of the stator bolts. however, that is a pathetic ground and grounds should NEVER go through a socket termination IMO due to corrosion /etc, and the voltage regulator grounds grounds directly to chassis. These are reasons that the chassis really should have a better ground reference. If you look at a more modern battery equipt bike, many will have a couple wires coming off the battery negative. One goes to the frame, the other to the motor. Yes, technically, the Banshee is grounded effectively because most anyone that has problems owns older or custom Banshees, however, the fact that it is prevalent enough to keep showing up says it ain't good enough. If you refer back to my post on this. a simple dedicated replacement of the entire grounding circuit wiring with bigger wire going right to the motor and frame is preferred. I remember people years ago being shocked by their own bikes due to potential (remember that word?) differences from frame and engine. That is what happens. I guess I should throw safety in there too that grounding the chassis will also keep you from getting zapped! lol EDIT: I wanted to expand on what I posted previously so as not to misdirect. I think I sort of tried to incorporate other ATVs and the Banshee. The Banshee does have a ground, otherwise the bike would not run. However, there is no dedicated ground from engine to chassis other than contact through the engine mounts, which is never advised or ideal. Simply running a ground from engine to chassis can both reduce down time, and protect yourself and electrical components in the chassis. many things ground to chassis ground and it is just not a good idea. Copper has roughly 50x more electrical conductivity than steel. Brandon Mull Engineering

The pressure on the gauge should not drop regardless. There should be a shrader valve in the very tip of the threaded insert. If they leak, the pressure will fall. Pressure should hold indefinitely.

Yes, if the TORS module is unplugged, that should not be your issue. Closely examine all the wiring and terminations (plugs). It is possible that you disturbed one of them during the rebuild. The B/W wire is the ignition kill wire. If it is taken to ground potential, there will be no fire. I recommend testing from any source of B/W (TORS plug) to chassis ground. If you have continuity, there is something grounded on the B/W. Kill switch, key switch, TORS, or pinched wire. You would also test Any black wire to chassis ground to make sure there is continuity.

I would suspect you still have the TORS system on the bike and messed wtih the throttle cable a bit when rebuilding. If the electrical system senses that one of the carbs is open a bit but thumb throttle is closed, you will not have spark. Look inside the carb backs and see if a carb is hung up a bit. Mull Engineering

I made the determination of 12ga based on the lighting coil output from OEM and aftermarket systems. A 200W stator at 14V is about 16A so 12ga will cover that requirement nicely. Technically you could use 14ga without issue but the durability of larger wire is better. Any ANY automotive application, the higher the strand count, the better. Higher stranding is more flexible (easier to use), and has a higher cyclic count (bend more times without breaking). Vibration can damage wire. Nearly any automotive wire will be fine, just don't go grab Romex from your garage wiring stash and stick it on your Banshee..

Yes, I should clarify that though the lighting coils and ignition coils are totally separated, they both share the exact same common/ground reference at the engine so whether you run lights or not, a solid ground connection between chassis and engine is required. Running a ground cable from a head stud, to the ignition coil is just fine and qualifies as a ground strap granted the conductor size is reasonable. It is simply important that when creating a ground contact point at the engine, as much Aluminum is interfaced as possible. Aluminum is a hugely superior conductor than steel. No, it will NOT make you faster, but it WILL make sure you get back to camp without a tow strap hooked to your quad.....Commonly referred to a the "tow of shame".

I had a couple messages regarding a recent post I made on chassis grounding so I will attempt to elaborate a bit to help. Many here have found themselves with electrical problems. Many people believe if you don't have voltage, you have a bad component. That is not always the case because every AC/DC voltage source requires a common or negative reference to complete the circuit. Case and point, you can remove the negative cable from the battery in your car and then take the positive lead to anything in the vehicle without a single spark. It takes the continuity of that circuit to make usable current and voltage. In an ATV, the electrical source is within the engine as a magneto or magnetic flux induced voltage supply. ALL voltage from that source will be AC and it can either be conditioned and rectified as DC power or anything in between. However, Any power supply requires a common or negative reference in which that is the engine case. Also being referred to as the ground which are one in the same for this discussion but not always the case. It is totally possible to have a separate common and ground reference but for safety, they are usually at the same potential. Now, some here fight with "ground" issues in which electrical devices do not operate correctly. If you will notice in many ATVs, ground references are made direct to the chassis in many cases. In my opinion, steel sucks as a conductor and causes problems but it saves OEM's money... Many Hondas had it right 40yrs ago by running dedicated grounds right back where they need to go....the ENGINE! The engine, being all Aluminum, is a great conductor. However, in the Banshee it may not be necessary to completely rewire the bike just to fix these issues but it does stand to reason that if you paint your frame, PC your frame, ride in salt, etc, you need good contact from chassis to each electrical component, BUT also from the engine to the chassis! If you PC your frame, you will likely have a thick coating between the engine and chassis, which will drive you nuts trying to solve the electrical problems!! There are a few ways to solve this, one is obvious, grind the contact points between the frame and engine, next is to supply a new grounding cable between the engine and chassis. These can be found on many bikes from OEMs today as well as cars and are a smart move. The last is to carry a ground conductor right from the engine to each electrical device requiring ground reference. IMO, Yamaha dropped the ball big time by relying on the engine/chassis connection for this electrical continuity and the cheapest and smartest thing to do is add a very simple, 12ga copper grounding conductor from any point on the engine cases, to any bare point on the chassis. I hope this helps with some of the electrical problems out there!! Brandon Mull Engineering

Another warning, make GD SURE that your engine mounts ground properly to the chassis. Remember this, the ignition source coil and lighting coil reference ground from the engine. If the engine does not have continuity with the chassis, you can ground components till the cows start singing and it won't matter because that ground reference does not make it back to the engine.

I agree with above. Sounds like either the eccentric bolt broke off or the shift claw slipped off the shift star. Either way, it does not sound like anything too serious....yet... Our billet shift star is made with longer drive pins so the claw cannot slip off the shift star. However, you still need to make sure everything else is in working order and determine what really happened. No deduction on "give a shit" points for flogging your Banshee when a life is on the line.

That is what we like to hear! Glad you got it figured out.

That is no kidding Chris. I have said for years, "if only the Haas machine was as good as the Haas control". That does not mean the Haas control is anything special but they are sure easy to use and look at. We have several Moris and Hitachis and sad to say, we LOVE Jap iron around here!!! If you are a machine wrench like me, you start looking at how things are built and Mori just makes sense and Haas leaves you saying "WTF were they thinking??" Little things like way covers that don't have enough angle to lose chips, a bed that does not flush chips, etc. I notice yours still have the table gutters on. Busted too many knuckles on those jokes to keep them. But, I have always liked that Haas GIVES you a few extra M codes and we have used them.... LIttle things like programmable air blast, etc are so easy with the Haas I/O. Okumas are super solid iron but I don't like their proprietary control. From what I hear, VERY good conversationals on the lathes but I like Mori with a near standard Fanuc.

No doubt side mount don't suck, mostly due to prestaging. We still have one of the older carousel Haas's and JESUS is that painful to watch. However, speaking of pain, try a Haas super speed VMC with a bad TC twin arm. Verified that a 10lb tool can be ejected clean through the lexan window, no prob...... Some people slow down the TC just for safety but come on....we make shit faster for a living. The thought of slowing down is not really a thought process....

Just order yourself a Mazak Integrex and tell the wife the vaca's are deferred for a while. Every machine has it's strong point and not always a better option than a live tool lathe fuck are they fun.

On the left? It looked like a pneumatic chuck on the right but the left looked odd. Maybe a specialty fixture for multiple components?

Hey man, what the hell is that to the left of your boring operation?

I just want to clarify, I do not intend to offend or discourage anyone from learning. As a matter of fact, some of the senior members know that I like to preach about education. However, I guess what caught me as a little wrong is this work is obviously very new, untested, and unverified, yet the member is "open for business" to charge customers more than we do to "learn" on a customer head. I guess over my 15yrs of building engines, I got tired of seeing hackjobs some people called "port jobs" that they paid big bucks for because someone said "I did my own so now I am an expert". There are people right here on this site that have done nothing more than copy port work and call themselves an expert but I will let that dog lay. IMHO, I simply feel the member should probably consider doing "several" freebie jobs and get some feedback, and run some more numbers before hanging the "open to take your money" sign. Machining heads is NOT rocket science and I don't try to imply that only we can do it, but you really need to know it is right before charging someone for it. Just as a couple of notes, The fly cutter concerns me greatly, both in terms of rigidity, and safety. Swinging that big bar in an ER holder with that skinny shank means that if it binds, you could snap the shank and the bar will be connecting with someone/something HARD. Also, deflection looks to be a big concern with that setup and I am certain if you put a mag base and indicator on the end and push it around a bit, you will get .010" deflection up and down. Fly cutters are NOT intended to remove big amounts of material, they are designed to take .001-.003" from the surface to create a final, finished surface. I am a bit concerned that if you are not using a neutral rake insert, both pos and neg rakes will cause the cutter to either deflect or dig in and with the largely interupted cuts on a head, you NEED rigidity if you want a flat surface. I am certain that though the surface might look nice, if we stick that on a CMM, it will have waves in the surface from where the cutter dug or deflected. IMO, you need to dump that setup entirely and if you are fly cutting, research inserts for that work. An integral holder will be much better but be advised that the machine itself could be part of it. I know one shop I was at recently about shit themselves when I proved to them on their brand new Haas VMC that I could push the spindle around my hand over .003" in any direction. Proves the theories of spring passes though!!! Brandon Mull Engineering