blowit

Take your gas cap off or loosen it and see if that changes it. Sounds like vapor lock to me. Brandon

Ah, I think I understand. You and your buddies are comparing bikes by how fast they go? If that is the case, in the ATV world, acceleration is what you need, not top speed. You are best with stock gearing with pipes and 20in tires. You wanna put the hurt on your buddies, invest in REAL tires!!! Seriously, I cannot tell you how many holeshots I have pulled in my racing days by just studying a track and selecting the proper tires. I feel there is no better line than the holeshot tire. They have several but they all will smoke your stockers and you will need to hook if you want to play with thumpers on grass and dirt. Bet on it. Brandon

Crap, sorry, I am replying to the wrong people here. Yes, your reeds can affect static numbers by not allowing crankcase pressure to be formed. That is needed to force air to the combustion chamber. If you have damaged reeds, you might take a closer look. Also, please let us know what comp tester you are using or even give us a pic of the very end that is threading into the head. That fitting MUST have a valve in it for accurate testing. Brandon

Carbs and pipes are not needed for static comp testing. The reeds should be installed though. If you are that now on comp with the reeds on, better do some lookin around. Brandon

You should be just fine with the 50/50 with that comp number. If you are mixing 92 octane with 108, you would< in theory, have 100 octane fuel. Now I really don't agree with than math because you still have fuel that is low on the crack scale. I do agree it raises the octane but not on an average scale. I always recommend one or the other. You may be just fine with standard pump fuel in that motor. Brandon

Sounds like carb slides are on the wrong sides. Cutaway at the bottom must be towards the back. Let me know. Brandon

You PMd me on heads and I am not sure if I can respond with this email system on this site. Please just shoot me an email from my website. Thanks Brandon Mull Engineering

K, you need to disregard the buzz. That is set on meters to like 10 ohms and below it just lets you know you are near zero resistance. You need to look at the numbers on the meter. If it is auto ranging, let it do the work. Refer to the book for the numbers. I am really not sure that coils is bad. You WILL have high resistance on the secondaries meauring off the two spark plug wires. Unscrew the caps, test the coil, and test the caps separately. You can either learn that meter or pull out your pocket book and buy some new parts that MAY fix your problem. Brandon

Follow wires from voltage regulator to head lights. Sounds like something is unplugged or a wire is pinched. Fi you are putting bulbs in the head lights and they are blowing, you have a regulator problem. The tail light is sometimes resistant to higher voltage because of higher resistance. Grab your multi meter and get to it. Brandon

Tell us what you are working on. What is the history with your problem. Brandon

I hope you mean .011. It is common to need to adjust ring gap a few thousandths. you might want to measure your bores to make sure they are really correct. I have seen it too many times. Piston no el-fit-o! Brandon

Some of those smaller motors are set up tight from the OEM. You gotta remember that piston mass, rod length, rpm, and such all play into how much squish you need. Those buck and quarters have very low reciprocating mass so they run rather tight. Brandon

Get that thing to the point where it will not start, pull and plug and check for spark, if it fires, grab a can of WD40 and shoot a little in both carbs and see if it tries to start. If so, you have a fuel delivery problem. Unscrew the bottom screw on the carb bowls and see if fuel flows out. This will tell you if the bowls have fuel. If so, do a carb clean and pay careful attention to the pilots jets. Go ride. Sounds like a simple fix from here. Brandon

You may be just unlucky but something to check is if there is an obvious area of the gasket that is eroded indicating possible detonation. I only say that because of the high temps you were riding in. If the gasket just failed, replace it and role on. If it was detonation or even preignition, you may have some carbon deposits or something causing some auto ignition. Just find the source or post some pics of your damage if you find any and we will help you get back to riding. Brandon

That is exactly right!! Volume of a given cylinder, squish area, velocity, clearance, and overall design all affect how a motor will respond with a given fuel. What you have to consider is you are testing "static" compression and that is no where near "running" compression numbers. As a general rule, the bigger the bore and stroke, the less static compression you can have before detonating. We are able to run a stock bore banshee at insane compression without problems but I ran my "honzilla" (250R with LT560 motor) at around 140psi on race fuel. That 560 pulls one big mouth full of fuel on the down stroke which changes everything. This is why we tune with numbers and not gauges. Let the gauge be a testing tool and bench mark. Brandon

I did not see your last paragraph till now but wiping those crosshatches off is what is called glazing and that is "exactly" what we are trying to remove when honing a cylinder. Those marks are VERY important for oil retention and the life of your engine depends on them. Maybe Fire guy can take on this exhaustive explanation of why but crosshatch angle and depth as well as what abrasive is used and in what manor all play into how an engine will run in and last. Why do you think those ribs are on the side of your new pistons?? A new engine will run hotter and you must be careful not to glaze the cylinders during the process. Brandon

I did state that wrong and meant just UNDER 200psi static. This of course depends greatly on air density. I am not sure of your elevation but 160ish with 19s around here would be considered low. I would say that a 60lb variance from new to run in is quiet a bit. Our motors will stay within a 15lb window from fresh to 2 hours to 50 hours. You may have some gauge issues there. The way in which a bore is honed matters greatly on run in time, life of piston and bore, and compression. Brandon

Now I am not sure of your elevation but those 19s with stock porting and a fresh engine should be pumping more than 110. You need to grab another gauge or borrow one. 19s should pump just over 200psi on a stock motor. We push our pump motors up there but you have to be real careful of detonation. You might want to back that off a bit to be safe. Your problems sound like carb balance. If you have not checked that after removing the carbs, you might want to check it. Brandon

At those prices, I would either stick with pump fuels, try some alky, or custom blend some fuel to raise the octane of your pump fuels. There are always other options but as stated, switching thing around all the time is not really worth the small gain would get from it. Brandon

Sounds like carb tuning and balancing. Might check to see if the needle on that side has fallen down. Also check the pilot jet for a clog. They will still affect mid throttle openings. Really sounds like carb balance though. Brandon

I think I was misunderstood on that last post. The diode would simply correct any ground loop issues you might have by not floating a ground. The full bridge rectifier will induce voltage increase when tested with an RMS meter because of RMS not capturing the peak voltage of the sinusoidal AC wave. Thus if you have 12.5V AC, you would end up with about 19V of DC before regulation. There is always more than one way to skin a cat. Brandon

We have several customers running our star with the shift pro kit without problems. Both part are designed with the same goal in mind but people are using them together. you would have to try it and see if it shifts too easy for your preference. Brandon Mull Engineering

Very much appreciated Washburn. We want to stand behind what we sell and try to offer innovative products. We don't mind helping out either. Its a business and a hobby for us. If your not happy, we want to know about it. Brandon Mull Engineering

I am real curious if you have done this or had problems installing a reg/rect on your ride? We have never experienced a need to float ground to the reg. That sounds like a ground loop problem that was cured by doing that. Those grounds are direct link to chassis and chassis referenced to ground so in effect you are adding a neutral. Interesting. I don't see any harm in doing it but I also don;t see a need unless ground looping is a problem. I simple diode will fix all of that. Brandon

As stated, you will need a regulator/rectifier to run a battery. The battery will act as a capacitor to further smooth ripple voltage. Make sure to fuse your battery right at the + terminal for safety purposes. Brandon