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About cr85racer12

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    MX, hockey, biking, training

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  1. I've called the WPC and they said that they treat and get very good results with ball bearings but of course they need to be disassembled first. I think with a very small (1/8in) carbide porting tool these could be ground down without too much issue. The problem would be reassembly. Finding super strong tiny rivets/pins that are the right size. This one might take some digging.
  2. Hey folks, looking to strip these bearings down and send in the balls / races for WPC Treatment. These are an old set of bearings so will be stripping these down first for experiment. Looks like these little rivets are holding them in. Looking for some opinions here. Drill them out? Rivet them back in with tiny rivets? I appreciate the insight. Thanks!
  3. cr85racer12

    New to VT, building MX track

    Moving to Burlington area, hoping to build my own track when I get there, Kitt are you still around???
  4. Thanks William1 And yes you're right, generally with a higher octane rating a few more degrees of ignition advance can be obtained. I just wanted to share the fact that Octane and effective octane are clearly different. I also just picked up a Dial-a-jet and was impressed by it, so I wanted to post up the good old forum. Could you inform us a bit about cam timing? I'd imagine perhaps a few more degrees of rotation can occur before the exhaust valve opens on the 2S? Could be wrong.
  5. Intrinsic and Effective Octane, there is a difference The Octane Rating of a fuel is defined by its ability to resist pre-ignition in a spark ignition engine. Octane rating has no effect on how much energy is contained in the fuel, but rather how efficiently the fuel can be controlled. High octane fuels are commonly seen in high performance engines because they are able to withstand high static compression ratios and high amounts of boost (in a forced induction engine, supercharged or turbocharged). The octane number is taken by comparing the given fuel in a test engine with another fuel (a mixture of iso-octane and heptane). If the fuel has similar anti-knock properties to a mixture of 90% iso-octane and 10% heptane, then the fuel is given an octane rating of 90. Since iso-octane does not have the highest resistance to pre-ignition of any fuel, it is possible for fuels such as aviation gas, methanol, LPG and others to have an octane rating higher than 100. There are 2 basic tests where octane ratings are tested. These are the Research Octane Number (RON) where fuel is put into a test engine at 600 RPM with a variable compression ratio, and there is the Motor Octane Number (MON) where fuel is put into a test engine at 900RPM with variable ignition timing to further stress the engine. In Canada and United States (and many other parts of the world) we use the average of these two numbers. This is denoted by (R+M)/2, we see this on the pump’s at the gas station. Now this is where things get interesting. How is it that the new Mazda 6 has a gasoline engine that runs at 14:1 compression ratio, using pump gas? Considering that is about the same compression ratio as Mitch Payton’s Pro Circuit Race bikes which are running full race fuel, there is a clearly a difference between intrinsic octane rating (chemical) and effective octane rating. The effective octane rating takes all conditions into consideration, and is a direct measure of what’s going on inside the engine. There are factors such as the latent heat of vaporization, the intake air temperature, laminar and turbulent flow in the ports, tumble and swirl of the mixture in the combustion chamber, and atomization of the fuel. All of these will play a role in the effective octane rating of an engine. One of the main reasons that the Mazda SkyActiv G engine is able to get away with such a high compression ratio is because it uses a high pressure direct injection fuel system injecting fuel into the combustion chamber at 3000 pounds per square inch!!! This allows the fuel to disperse with the air so well that nearly completely vaporizes in the mixture, turning from a liquid into a gas. As the liquid turns into a gas, it absorbs heat due to the latent heat of vaporization, which in turn lowers the temperature of the given air/fuel mixture. The mixture becomes exceptionally atomized and the resulting lower temperature and stratified charge allows the fuel to further its resistance to knock. Now you might ask, how does this play any role in the world of dirt bikes? Well take a look at the new twin-injection setup on the fuel injected Kawasaki motocross bikes. There is an initial injector just inside the airbox that delivers fuel into the intake stream so that by the time it reaches the intake valve it is completely vaporized, cooling the intake charge and optimizing the atomization of the mixture. Then a second injector much closer to the engine injects fuel before the intake valve increasing the fuel density of the mixture. This system allows for the benefits of a fuel mixture where the fuel molecules are extremely well dispersed with the air molecules, and the vaporized fuel has absorbed heat going into the intake manifold. This setup allows for higher compression ratios due to its high effective octane from the manner in which the fuel is injected. There are other ways to increase the effective octane of an engine. A very popular method that has been used for decades is injecting a fine mist of water into the intake stream (aka Water Injection). Because water has among the highest latent heats of vaporization, its ability to absorb heat in the intake manifold is extremely effective, and don’t worry about corrosion, water is already a product of combustion anyways. In carbureted engines, popular products that increase the effective octane rating include the Dial-a-Jet by Thunder Products. This is an injector that is tapped into your carburetor, and uses the acoustic pulses (sound energy) of the motor to excite a vibratory mechanism that mixes air into the fuel and produce a stratified charge. The added benefit of this system is that an engine that is operating rich produces a deeper sound (lower frequency) which de-excites the vibratory mechanism, adding little fuel, and an engine that is operating lean produces a high pitched sound (high frequency, pinging) which further excited the vibratory mechanism and injects more fuel to combat the lean condition. Yes, it is essentially auto-tuning with available external adjustment. Engine vacuum also plays a role in the Dial-a-Jet, similar to a regular carburetor jet, except due to the fact that the fuel molecules are already stratified with air and are approximately 10% the weight of regular fuel molecules, the mixture travels to the engine much faster and is thus more responsive to the conditions of the engine. Because the mixture is pre-atomized before entering the intake tract, this setup offers the same vaporization cooling effect and thus a higher effective octane. Other things such as porting are able to improve the velocity of the intake charge, which can allow for increased volumetric efficiency of the engine. The design of the combustion chamber can allow for a swirling effect (when looking down at the piston’s top, the mixture is spinning around clockwise or counterclockwise) or tumbling effect (when looking at the piston from a side view, there is a clockwise or counterclockwise motion of the mixture). Both of these factors aid to increase atomization. Running 110 octane in your stock engine will yield little to no benefits. High octane fuel is only necessary when combating against high compression. Delivering the fuel in a cold, dense, stratified charge will mimic the effects of a higher octane rating gasoline, and this is due to the fuel’s effective octane. Intrinsic octane is merely the octane’s number, effective octane is how the fuel is implemented in the engine and is not so easily given a numerical value.
  6. cr85racer12

    Lambda values on a 2 stroke..

    14.7:1 is stoichiometric, but you will make the most power in the 12.5-13:1 range. Amsoil makes a 2 stroke oil that claims it can be run at 130:1 in racing applications. I would use that to keep the sensor functioning.
  7. cr85racer12

    Running methanol two stroke.

    I will tell you what I know about methanol and its benefits, but there is still much more to know. Methanol does not contain nearly the same amount of energy as gasoline. The BTU count is about half that of gasoline at 57,000 BTU / gallon compared to gasoline 116,000 BTU/galllon. This means that if you want to run your bike purely off of methanol you will have to run much more fuel (ie much larger jets, etc) in order to make the same amount of fuel. The main benefit behind methanol is its octane rating. Octane can be thought of as the fuels ability to be compressed before self igniting. This means that methanol is able to sustain a higher compression ratio or the mixture can be ignited a few degrees earlier in the crankshafts revolution (spark advance). Methanol will allow motors to run at much cooler temperatures. Methanol has an exceptionally high latent heat of vaporization. This means that as methanol turns from a liquid to a vapour (vaporizes) it absorbs heat around it, making the intake colder and thus more dense because it will contain more oxygen molecules. The higher volume of fuel also helps to cool the intake charge. Methanol is only beneficial if you're running a very unique setup. You can also opt to run methanol injection. This is where you introduce a mixture of methanol into the intake tract with your regular gasoline. Methanol will help to cool your intake charge as well as raise your octane rating of your fuel. Many people opt to mix methanol with water because water has among the highest latent heats of vaporization (much higher than methanol) and water helps to reduce peak cylinder pressures associated with knocking. A relatively simple implementation of this would be to use a Dial-a-Jet system injecting methanol / water or a fuel of choice. http://www.thunderproducts.com/dial_a_jet.htm This is what I plan to do on my motocross setup 2006 YZ 144, as in theory it will allow me to run an aggressive powerband for top end power without melting the top end. Hope this helps some
  8. cr85racer12

    Bike idled then died, now NO spark

    2006 Yamaha YZ125, 3 hours on top end. Its the spark that I'm concerned about. I found the Yamaha Service Manual has the procedure for checking the electrical system though.
  9. Had the bike running at the track on the stand as I was getting all of my gear on. The bike then stalled and I replaced the plug thinking it was fouled. Wasn't starting. I checked for spark and nothing. I can actually hold my hand on the plug while cranking and I don't get zapped. What is the process for diagnosing my ignition? Thank you for the help!
  10. cr85racer12

    DRZ250 idles to high

    Possibly a case leak? Does it run lean under idle? You can clean the plug and let it run for a bit at idle and then check the colour of the plug. If its running lean then it could be sucking in air from somewhere. Your slide should be smooth too, so that could be an issue. Also you didn't mention anything about playing with your idle screw? Did you fiddle around with that?
  11. cr85racer12

    Keeping a Mid/Top YZ144 Cool.....

    Timing and squish are stock, though I've been advised to retard the timing just a bit. I do plan to fiddle with the jetting, fiddle with the timing. I'd guess that distilled water would be best to run to keep temperatures down then?
  12. Hey guys, been reading some horror stories on YZ144s (more than I'd have liked to have read). I had an LA sleeve installed in my cylinder, I believe it is a steel sleeve and it is not coated like the aluminum cylinder walls. I want to be running mid to top end power. Right now, I have an FMF Fatty Pipe (I had an SST and LOVED the power but according to Eric Gorr they run too hot). The fatty on the 125 made the power much more broad, but the bike felt slower as the top end was much weaker compared to the SST. I am not using race gas. Its too expensive and too hard to find especially in my area. Will be running Klotz Castor Oil at 32:1. Will be rejetting but haven't done that yet, 144 kit is not in the bike yet. I've heard go up a few on the main and maybe 1 or two on the pilot. Is there any true benefit to running a performance coolant, such as Engine Ice? Should I be looking into larger capacity rads? They have them on Ebay for just over 100 bucks shipped, claimed to have 40 percent more cooling capacity as they are double rowed rads as opposed to single, but that is just their claim... I'm actually seriously looking into water/methanol injection, but thats another story, and that won't be immediate. Looking for some meaningful advice, preferrably those who have some experience with 144s or bikes that have run overly hot in general. Thanks!
  13. cr85racer12

    Building your own dyno

    Dynos are pretty amazing tools. We have a dyno at our school which is a brake dyno as well. Its made by this company. Their website is an excellent place to learn about building dynos for all applications. http://www.land-and-sea.com/kart-dyno/kart-dyno.htm
  14. Thank you very much for all of the input guys. And you are absolutely right about the conditions changing if I were to run dry. Actually, vortex and other ECU companies offer external adjustment of maps via a handle bar switch or ECU mounted dial with numbers. If I were to run dry I could just go back to a base tune. I will obviously be keeping my eye on the system to make sure I know when to switch, Also, my interest is leaning me towards specifically water, it would make the system less complicated. I will run a mix of this http://www.klotzlube.com/techsheet.asp?ID=51 product in order for the water to contain lubricating properties and not displacing oil too much. Also, I live in very humid weather which in Southwestern Ontario in the summer. Very often 100 percent humidity and this is where the water is saturated with water already, in which case my injected water likely won't vaporize completely, or at least as easily. Also numbhands, I can run this water injection in a way that it is proportional to engine load, which is EXACTLY how a carburetor works. Pretty cool concept, a lot of guys actually run these for water/meth setups in EFI engines because of their convenience. Dial a Jet http://www.thunderproducts.com/dial_a_jet.htm Fuel injection would be sweet, but maybe like a year from now and I could tap into the block and do direct injection but that's only a dream for now. Would love to make this a competitive bike as I will be racing in the Open Expert class at my local club (smaller club) and it would be pretty cool to see a small bore up to speed. Also for the exhaust injection, it would be nice to have it vary the amount of water so that the powerband could be broadened to even a greater extent, but controlling that would be pretty tough. Double, but tough.
  15. KX450f63, maybe you could try starting off with an insert, and then perhaps modifying it to fit your tastes. I've had one of these on my bikes, worked well. http://www.hyderacing.com/db_dawg.htm