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We have previously operated with economical USPS shipping to Canada to save our customers money. However, in this instance, the customer seems very sharp on what they are doing and a near obvious scam. The thing buyers do not realize is there are several consumer black lists for merchants so if a CC charge back is issued, a customer can be black listed by a merchant and blocked from future purchases by other merchants. This type if fraud is a $12B industry in the USA alone. It is enough that us merchants are having to fight back and it usually comes at the cost of higher prices or shipping rates to account for it. Always frustrating for those that are legitimate though. Fortunately, 99% of the people here are straight shooters like us. That 1% really changes things though.

As unfortunate as it may be to those legitimate buyers outside the USA, due one Canadian buyer, we are looking to terminate all foreign business. We have never lost a part to any country yet. However, one buyer indicated they did not received their items not once, but twice. We simply cannot afford losses like this and find it extremely unlikely that a package would get lost twice to the same buyer. We are reviewing our options at this point but I do apologize to any foreign customers this might affect. Brandon Mull Engineering

I have never seen a Banshee without resistor caps. Actually, if you look elsewhere in the book, you will find a test for that resistance. I think Yamaha was chasing the elusive CDI failure issue and wanted those resistor plugs to further protect the CDI. I personally believe that is more of a vibration issue. I did not mean to mislead, the BR8ES plug WILL run all day in the Banshee. However, if you are running big girl carbs or alky, you can notice the plug difference in how much gap they will handle.

You may be posting next week with TORS issues. To be honest, you did something to the cable system that is still not corrected and when it finally corrects itself, adjustments will be off. You basically had two separate issues, head stud leak and throttle cable issue. It is common to see the Y or splitter issue on the cable. Once you wiggle and seat them back correctly, the slide issue will solve itself.

About the max deviance you would ever want to see in a bore is .1mm. I agree with other posts that your cylinders are in need of a bore fo-sho. You will improve piston life and reliability drastically by doing so.

A B"R" plug is a resistor type plug that incorporates an internal resistor to help absorb the back EMF or collapsing voltage that is typical of an ignition system, from getting back into the wiring system and causing electrical noise. Back EMF not only causes audio system noise but causing electrical system failures. However, the plug caps are already protected so doubling this up is only working against you. The VERY reason you want to avoid the "R" plug is that the Banshee has a very limited ignition system anyway and the very resistor in the plug that helps retard electrical noise issues also reduced effective voltage to the business end of the spark plug. Remember V=IR so any added resistance in the current path WILL cause a reduction in spark energy in the cylinder. In short, use non-resistor type plugs and nothing else in the Banshee unless other stated for aftermarket components. Brandon Mull Engineering

I am a little confused by what you are explaining but I will offer some 101 fundamentals to maybe help. The lighting side coil is a shared or single phase wind with chassis ground reference. This means one wire to ground = max stator potential. The reg works to shunt power to ground at a given voltage. They usually work or they don't by design. Because the system has a very low power potential but higher voltage potential, it is possible for larger electric loads to not cause problems with no voltage regulation but small loads (tail light) to blow easily. As the load increases, the voltage will naturally decrease because a load is doing the same thing a reg would do which is shunt or eat power. A blowing tail light is a sign of high voltage. Low voltage is a sign of either a weak stator or leakage to ground somewhere usually. It is possible that the reg is failing and I have seen it but reg leakage without total failure is rare. The best way to test this is amperage from the stator at the low watt condition. Test in mA for accuracy. Remember that the bulbs wattage is at 12V. if you are not at 12V, you must reduce the voltage in the calculation to estimate wattage. IE, 12V/55w = 55/12 = 4.58A. V=IR, 12/4.58A=2.62ohms. At 7V, 7V/2.62ohms=2.67A, 2.67A*7V=18w. Not trying to baffle you with numbers but trying to help understand that half the voltage does NOT mean half the power. You need to know how much current you should see at a given voltage to know if the stator is doing what it should. You should test current at no place else than right off the stator. Also, remember that many meters, including your Fluke, is designed to work best at 60hz. The banshee AC power is all over the map and a function of RPM. A scope is the only true way to look at the power from the stator due the changing frequency. The peak the peak voltage is analyzed, then just take the root mean square (RMS) of that and you got it. Brandon Mull Engineering

I did not make it through all the responses but thought I might throw some hints out. A stator has nothing to do with detonation at ALL. However, the pulse generator does. The PG timing is VERY relative to the clearance gap it has. The main issue here is the assumption that if you set your stator plate at X degrees timing, you think you have X when you have Y. The wind of the PG makes a difference in the voltage rise of the PG pulse back to the CDI which then determines the advance. As with all digital ignitions, there is mechanical and electrical advance. The CDI advances ignition relative to TDC regardless of stator plate adjustment. The plate moves everything up but the CDI is constantly changing the advance. Detonation can still occur at a plate adjustment of 0 degrees if things are not built or adjusted quite right. Somewhere around here we have the CDI timing curves relative to RPM but IMO, the timing light is the magic tool to end the madness. It does not care who did what, all is cares is when the plug fires, I fire my strobe and that strobe will tell you where the crank is when it fires. And because the Banshee did not know what 3D mapping was, throttle position does not care at all, just RPM. As always, I recommend you all customers to start with 0 degrees plate timing and move up from there in 1 degree incs. Just because one bike is set at 4* and another at 8* does NOT mean the actual plug timing is that different. The PG is a rather stupid device. They are proven rugged but IMO, there are much more accurate ways to relate crank position to the CDI like optical. I was really surprised to see the new EFI wave in ATVs follow with the PG ignitions. I figured they would be a little cockier than that.

I replied to your PM. There are a few things to check. Make sure star seats properly against the shift drum and check the spacer that is under the return spring on the shift shaft. They can wear shorter and cause the shift claw to run closer to the star than normal.

I really need to determine which flavor is most needed. From our current design, we would provide basically factory geometry, with our extended pins, and no neutral stop. This should be the desired profile for any neutral down configuration IIRC.

Yes, our detent will help find neutral by rolling up on the neutral spot smoother without any catchy rotation as typical with the stock roller. It also has a much wider contact surface with the star to better respond to the contour and stops of the star. HOWEVER, neutral on a 1D-5UP sequential trans is a double edged sword. Typically if they find neutral better, they also like to find neutral during riding too. We try hard to split those lines but finding neutral while in a race situation is a much worse deal for most. We have a lot of racers on pavement that run 1st gear starts in which neutral can be a big problem. We have made recent refinements to our neutral stop to improve this without causing accidental neutral stops. Brandon Mull Engineering

The star works great with the shift pro and we even designed a detent roller bearing that installs on the detent arm for a lot less money. However, we have been told by a few that using the shift pro spring can cause them to jump gears so we recommend using the stock detent arm spring. Finding neutral is an issue that is based on a few design flaws in the Banshee trans.

Yes, these are heat treated.

Your PM box is full. shoot me a message or email at our website. Thanks

Coupelx, email me with what you are needing. We are setup to run heads right now so would like to knock a few out late this week.

We have a few flavors in stock and just though I would put the word out if anyone needs one quick. These are all machined and ready to go. 4mm stock cyl, 64-66mm bore, race fuel 4mm stock cyl, 64-66mm bore, alky 68mm cub, race fuel Thanks! Mull Engineering

As you folks know, we machine a LOT of Banshee heads. We need some extra cores in here. If you have a stocker, or two, or 10 that you want to sell, please let me know along with a price. Also, we have a few flavors in stock right now. 4mm stroker stock cylinder, race gas 4mm stroker, stock cyl, alky 68mm cub, race gas All can be provided with or without core. Thanks! Mull Engineering

We are going to follow right back up in about 3 weeks and take a look at the override needs. I would invite you guys to PM or email us with preferred requirements and reservations for them. I think there was some concern over the small market for them. I would like to know which designs are most needed.

We have stock of our ever popular billet shift star. For the new guys, we designed a fully billet shift star with improved geometry over a modified stocker, we improved the neutral stop to eliminate the annoying neutral hang up when shifting between 1st and 2nd, and lengthened the shift pins so the shift claw can no longer slip off the shift star and ruin your day. Improved shifting performance and increased reliably. We provided a small tweak to this latest revision of stars with adjustments to the neutral stop area. Some found it hard to find neutral so we back cut that just a touch more to improve it even more! These have been popular and hard to keep in stock so get yours while you can! http://www.mullengineering.com/sc/store.php/products/yamaha-banshee-yfz-rz-billet-shift-star-shaft-drum-transmission-race-drag-sand-shifting-hard-online Brandon Mull Engineering

I usually would not reach for a castor base unless using alky. I would probably run nothing but semi synthetic and 4mm at 32:1 and 10mm at about 28:1 for the first so many hours and if no scuffing, got to 32:1. I am a firm believer in feeding the oil and though I do like the synthetics, I prefer semi or castor with richer ratios. More oil will get you better ring seal and better piston skirt seal not to mention that the crank will love the most you want to give. However, like I said, synthetics offer reduced deposits, possibly cheaper to run, and great for recreation riders who don't like the stink of the 2 stroke. Plated cylinders have less friction and perform good with less oil. Softer ductile iron bores like the oil.

It is pretty important when talking about oil ratios, to segregate them into their oil type as well. They all will have specific optimal ranges. Amsoil will be a full synthetic product that is safer to run at leaner oil ratios. One of the biggest concerns with higher HP builds is wash down of the cylinders from liquid fuel in the intake system. In our experience, you really need a big bore or stroker to warrant any extravagant oils. 350s seem to last as long on full synthetic as semi synthetic like Yamahalube. Our pref would be Yamalube or comparable semi synthetic based on price and performance. Full synthetics however are getting cheaper to run and due to the reduced ash deposits, cleaner burn, and leaner ratio, they are certainly something to consider. You might also step away from the big Amsoil name and compare some other synthetics as well. I would usually recommend them at about 45-50:1 for most engines without issue. Brandon Mull Engineering

I would have to check in the shop. shoot me an email and I can let you know. We used to stock both axles because of all these clutch rod and gear welding issues.

I do not recommend anything short of a pancake bearing mod. the ceramic ball will not "gall" (tendency of two like metals to weld with heat) but the problem still exists which is that there is a LOT of pressure from boosted clutch springs or lockup on that ball. The worst case is trans spinning at full rpm (top speed), and engine at idle. These started to become a big issues on inertial dynos. "When topped out, pull clutch and allow to coast to a stop". That will kill them every time. The rod ideally spins the same rpm as the primary trans axle. The pressure plate and outer clutch hub spin at an rpm relative to the crank. The higher the delta in there, the worse things get. The ball was a shit design from the word go. Honda did it right. Mull Engineering

I would personally advise against it unless you wanna go for broke and weigh 40lbs. I would have to do more with the exhaust and still super tight and end up with a razor for a power band due to the change in xfer due to the crank change. I would personally recommend a different set of cylinders for that build. However, if you are stuck on them, we have, in the past, machined the bottom of cylinders to cheat this and custom machine the head to work. This was before Cubs were the rage though. You can get to that point of diminishing returns. Mull Engineering

If your 65.50mm bore is still good, I would recommend boring the other to match and run 65.50mm pistons. No sense in resleeving unless you really have to.