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Found 188 results

  1. pschultheis

    JD Jet install

    I'm going to purchase the Powercore 4 and want to install the JD Jet Kit at the same time. Are the jets difficult to do on your own if you have never done one before? I hear the instructions are great on the JD Kit. This is a 2008 WRF
  2. Briley1226

    Yamaha YZ426F (2000)


    Very strong and powerful.
  3. craydds

    Kawasaki KLX300R (2003)


    Great bike for a "play bike".
  4. burgesshoward

    Honda CRF250X (2006)


    Awesome bike. Everything that I could want in a bike.
  5. wrcasey

    gnarly issues

    I have a 13 wr250. I just installed a gnarly headpipe and stealth silencer. I will not be able to begin the jetting process until next week. will i be able to go out (light trail riding) this weekend without adjusting the carb? I was under the impression that most offroad bikes ran rich??? can anyone elaborate on this for me ...thanks
  6. I took my bike in for my first service and I already installed the MRD exhaust, 3x3 and a JD Jet kit and they said they took my bike on a test ride and they said I need to change the JD jet to the dyno jet. My bike does backfire a lot off of decal but I though that was normal for these bikes to backfire a lot with a open exhaust. I'm not sure what jets i put in but I put the biggest jet size in. I told the dealership no but they said it's really bad to run like this. Does the dyno jet have a bigger jet size? Do I need to change the jet needle position? The bike runs very good though.
  7. Hello, I have a 2013 drz400sm with a MRD z-pro full exhaust system and a JD jet kit with the extended fuel screw. Could anyone tell me what settings I should use for jetting it? I live in Leavenworth Kansas which has an elevation of 840ft meaning I should use the blue needle. But, in Kansas the weather in summer is bipolar and can go from hot (above 85°F) one day, to cool (below 75°F) the other; and according to the paper I got with the JD jet kit, it recommends that if your tempatures are over 75°F you should use the red needle. So im not sure which one I should use and I'm not sure what settings I should use with regards to the main jet, pilot jet, etc. The bike is all stock minus the MRD z-pro exhaust. I'm new to jetting so if anyone could help me out, it would be greatly appreciated.
  8. Hi guys, First of all I am new here and very new to the dirt bike scene hence this last minute question. I own a 2011 YZ450F and I am going riding with some friends this weekend in Taylor park Colorado. My bike will be fine seeing as thought it has fuel injection. My other 2 friends, one has a 2006 KX250F and the other fried has a 2001 YZ250 2 stroke. We are all pretty new to this but do enjoy having some fun once in a while. So about a year ago I took the one friends yz250 with my other friends kx250F to Taylor park which altitude is about 7500 - 10000ft and the bikes ran like crap!. The 2 stroke ran better than the 4 stroke but both bogged and had almost no power at all. We are getting ready to again and I was honestly hoping someone could tell me what jets we would need for these two bikes at this altitude? Any help would be greatly appreciated.
  9. TheSuperMotoTard

    Suzuki DR-Z400SM (2014)


    This thing is a wheelie machine. Decent offroad as well. I love it, this bike is my kid.
  10. DirtRockr

    Kawasaki KLX300R (2007)


    Original owner, bought new off showroom floor in 2010. Mods made it a great woods bike! Street plated but geared for woods. Only complaint...no button. That would've gave it 5 stars.
  11. chemomche

    Suzuki NECJ suzuki needle

    1 review

    GENERAL INFORMATION Suzuki needle from RM250
  12. Here's the quick back story. - cut gray wire - did the AIS removal - JD Jet Kit (180 main, Red needle 3rd clip position, I'm in Oklahoma @ 1200 or so feet) - opened up air box a bit - fuel mixture screw - stock exhaust It ran perfect fine. December hit, ran like poop. Edit: don't know where to put this is but at this point I was fouling plugs left and right..way too rich Messed with the needle a little, put in the blue needle..didn't help (thinking it needed richening since it's cold). Changed it back to red needle since it wasn't that issue. About Feb. put on a slasher exhaust (not my choice, a friend did it)..really had not change...it's almost like having my stock. Still having issues where it's sounds like poop. has no power like it's fighting something to go. Worked on it with a trained tech (friend). We messed with the main jet a bit. seemed to work..ran great for one race. then acted funny again. (warmer weather is approaching) This has gone on all through this last summer. Hasn't run right. Thought it was water in my gas...drained everything out. changed the check-valve hose on the tank cap to a regular hose because sometimes that messes crap up. Floats are fine, checked them the two times I've had my carb off actually three times I've had it off. Bad gas is ruled out...I just go to the pump and fill it up with 91 octane 100% gas..just to rule out old gas...my tank is good for about 50 or so miles so one tank is good enough for doing one ride. I make sure to not get water in the airbox when power washing by blocking it all off and not running my bike after a clean up just incase water somehow slips in somewhere. I just let her air dry once I wipe her down with some clean rags... Are they called valves? Please excuse the fact I'm still learning here. But I had something checked with those thin pieces of metal to check the measurement gap thing just to rule out whatever it is you rule out when checking that..i'm having such a mind blank on that and I apologize. Just know that i think it was valves and we checked them. This past time at my mechanic friend's house we changed the pilot to a 45 from the stock 42, the main jet is still a 180, leak is I think I 70 since that's what JD jetting suggested in the directions when I first did all of this about a year ago. My fuel screw was 1 3/4 turned out. Ran GREAT that weekened when I went out for a ride. Temperature when I did all this was in the 40's. Red needle clip position is at 5 now (i know this is a lot) we were also accounting for colder weather in the future. My next ride was at an mx track, not that that's important but nonetheless it was there. Ran fine for a few laps...she got all warmed up and decided to started choking on the mid range throttle which is generally tied to the needle. I decided to call JD and ask them about jetting. He said the 45 main is WAY TOO BIG for my bike. Therefore today I'm changing it back to the 42. Putting my needle clip at position 3. Basically these are the settings I had since the beginning. I should also mention my accerlator pump deal should be all good and the last time we had the carb off or while we were putting it back together we made sure it was squirting gas correctly and not hitting the little door do-dad. I took out my spark plug just to start from new. It was black of course (at least it's not white). to me black is normal. I've fouled plugs on this bike so I know what too black is...regardless. I changed the oil to start new on that as well. Cleaned my air filter. (wasn't very dirty to begin with so that's ruled out as well) I'll probably dump the gas out and get a fresh pot. My oil has genearlly always smelled of gas which tells me it's not burning it all off..way too rich. And as much as I heart my mechanic guy he keeps thinking it's not rich. Most people think it's too rich including myself. I'm almost wanting to go to the 175 main just to see what happens. That's what I'm going to be doing is trial and error. Writing it all down, testing her out, writing down what happened and going from there. I'm just wondering if anyone else had had these issues and what you've done? Here's a video of what it sounds like..please note that there's not pop on decel so please don't mention "lean"...my other mechanic buddy that works at honda, he rode my bike since he crashed his and had to go get the truck..when he rode it he said it felt rich...it's got to be rich, it just has to be. I'm just so frustrated and can't wait to figure this out. I just hope I'm not chasing the wrong thing. My other thing I'm going to do is check the ignition coil just to make sure it's all good. I need to go buy a meter though. Here's the video: (hopefuly it'll work) https://www.youtube.com/watch?v=3zOvLYxoQBs William, I hope you read this..you always talk about carbs!
  13. I received my MRD SSW exhaust today that I have been wanting for a long time. I'm trying to decide if I had unrealistic expectations or if something with my jetting is wrong. My bike is an 05 400e with 3x3, slant FCR with Eddie mod, and I previously had just a Yoshi RS3 slip on. I was happy with this but saw people raving about the SSW so I found a used one and purchased it. My jetting is 160 main, EMN on clip 3, 45 pilot, screw is 2 turns out, and linked ports on pilot air jets. It ran perfect with e header and RS3 open and with the quiet core when on trails. I rode it today before switching exhausts so I could really feel the difference between exhausts when UPS showed up. So finally installed MRD an hour later when it came and went for a ride and just didn't seem to run right. It would barely power wheelie in second where it would easily before. Thought maybe it was lean so went and put the sparky and quiet core in thinking that would help but it then would not wheelie in second at all. The top end felt great pulling hard with the MRD in both ways but the torque difference made me want my old exhaust back. I ride a lot of trails so maybe the SSW wasn't a good idea but figured it wouldn't be to bad. I did play with my db meter quite a bit today trying to get some data on noise. I did the readings at 20" at a 45 degree angle from the tip. I taped the meter on a camera tripod so it was always in the same place. I don't have a tach, so I made a mark at approximately 1/4-1/3 throttle so they would all be taken at the same rpm. 05 DRZ400E, 3x3, FCR E Header with open Yoshimura RS3 slip on. Idle 90db Throttle 100db E Header with RS3 slip on and quiet core. Idle 85db Throttle 96db MRD SSW Open Idle 98db Throttle 107db MRD SSW with quiet core and spark arrestor. Idle 92db Throttle 101db
  14. spaceboy

    Honda CRF450X (2005)


    Great bike. Like the dual sport ability.
  15. IamRooster151

    Yamaha YZ250 (2014)


    Great all around bike, from mx to offload, competition to recreation. Easy to maintain, plenty of power, light wight and "flickable".
  16. ThumperTalk

    Dynojet Research Jet Kits

    22 reviews

    5% boost in horsepower Maximizes carburetor performance Includes step-by-step instructions
  17. Is there drool "spooge" running down your silencer at the end of a ride? Does your bike smoke at operating temperature? Do you foul plugs on a regular basis? Is your throttle-response poor and boggy? If you answered "yes" to any, or all of these, your problem likely lies in your carburetor jetting. The first step to jetting is setting the correct float height. Article by: Faded "Here are a few words and some pictures I put together to help eliminate the confusion in setting your float level. Obtaining the correct float level is of the utmost importance as it can affect all jetting circuits. THE FLOAT LEVEL IS THE FIRST STEP TO PROPERLY DIALING IN YOUR JETTING. It should be checked and/or set before you even think about swapping brass. By altering the volume of fuel in the float bowl you can vary your fuel pressure and affect your jetting. More fuel in the float bowl will create more fuel pressure and result in rich(er) running conditions and vice versa. You’ll need to first start off by removing your carb. Be sure to clean the surrounding area to the best of your ability to avoid dirt and debris falling into your carb, or worse, your engine. After you’ve removed your carb I would suggest a thorough cleaning using carb cleaner (or equivalent) and compressed air to ensure that all jets and passageways are spotless. Avoid using wire or other tools to clean orifices of jets; it’s all too easy to alter their original designed dimensions. After your carb is clean you can now set your float level. The picture below will allow you to become familiar with the parts that are responsible for maintaining the correct float level in your carb. There are four basic parts, the floats themselves (part of the float assembly), the float assembly tang, the fuel inlet needle valve, and the fuel inlet valve seat. (Float assembly pivot pin not shown.) It is always a good idea to remove the float assembly pivot pin (already shown removed) and extract the float assembly and the fuel inlet needle. The fuel inlet needle is a wearable part and over time can deteriorate. A worn fuel inlet needle can contribute to an irregular float level. Most fuel inlet needles consist of an internal spring loaded bumper (which contacts the float assembly tang) and a plastic or Viton (rubber) tip. Inspect the fuel inlet needle tip for wear and/or damage. To give you an idea, Eric Gorr recommends replacing the fuel inlet needle/seat assembly every two years. I’ve found that the average cost it around $15 for both parts. (Fuel inlet needle shown with Viton (rubber) tip. The Viton is used to isolate the fuel inlet needle from vibration and to create a better seal against the fuel inlet valve seat.) Now that you’ve made sure you aren’t going to have any issues from worn parts you can reinstall your needle, float assembly and float assembly pivot pin and continue on to set your float level. The float level measurement is taken from the top of the floats (when the carb is positioned upside down) to the gasket surface of the float bowl as illustrated in the next picture. You can use an open-end wrench (sized per your spec), a small metric ruler, or a float level gauge. The tolerance for your float level is usually around +/- 0.50mm. When setting the float level be aware that the spring loaded bumper on the fuel inlet needle valve may have a tendency to compress under the weight of the float assembly which will skew your measurement. Before you obtain your measurement you’ll need to make sure that the float assembly tang just barely makes contact with the spring-loaded bumper. Sometimes it is easier to hold the carb body at a 45-degree angle to avoid compressing the spring in the fuel inlet needle. If you find that your measurement does not match your float level spec then you can carefully bend the float assembly tang to achieve your desired measurement. Be sure to recheck your work, and if you feel confident that your float level is spot on then you can reinstall your carb and get back to riding." END OF ARTICLE Now that you know that you have the correct float height, you can start swapping out brass. Words of Assurance: Jetting isn't hard and comes with practice. You're not going to mess your bike up unless you make huge changes. You WILL be able to tell if your bike is running lean enough to be in danger of seizing. So, don't worry. Article by Spanky: "Throttle Ranges: Pilot Jet/air screw:0-1/4. Needle Jet:1/4-3/4 Main Jet: 3/4-Full open A correctly jetted carb makes a tremendous difference in the torque, midrange pull, top-end pull, and over-rev of your engine. If you have never jetted your bike correctly, you will almost certainly gain some performance at some point in the bike's power band. A cleanly jetted pilot circuit can be the difference between having to clutch the bike out of a turn or not. The needle can make all the difference in the world for the power of the machine in most situations, as it controls the throttle range that most riders spend most of their time using. A correctly sized main jet could mean the difference between being able to rev out high enough to not have to shift one more time at the end of the straight, or the power falling flat on top and requiring you to make that extra shift. The only way to know what jetting changes you will need is by trial-and-error. No one can give you jetting specs, because every bike is different, every rider has a different style, and jetting is totally weather dependent. Jetting is fairly simple, and is a useful skill to learn if you ride a two-stroke and want it to perform at it's best. It's very important that you start with the pilot circuit. The reason is simple. The pilot circuit affects the entire throttle range. When you are at full throttle, the main jet is the primary fuel metering device, but the pilot is still delivering fuel as well, adding to the total amount of fuel that your engine is receiving. Before you start to rejet your bike, you need a clean air filter, a fresh plug (actually you need several plugs to do plug-chop tests for the main jet), and fresh fuel. One important detail: Make sure the engine is in good mechanical condition. If your engine has a worn top-end, fix it first. Trying to jet a worn out engine is a waste of time. The same goes for reeds that don't seal properly, and a silencer that needs re-packing. Before you start the jet testing, Install a fresh plug. Warm the bike completely, and shut it off. As already stated, start with the pilot circuit. Turn the air screw all the way in, then turn it out 1.5 turns to start. Start the engine, and turn the idle screw in until you get a slightly fast idle, or hold the throttle just barely cracked, to keep the engine idling. Turn the airscrew slowly in, and then out, until you find the point where the idle is fastest. Stop there. Do not open the screw any farther, or your throttle response will be flat and mushy, and the bike may even bog. This is only the starting point, we will still have to tune the air screw for the best response. Now is the time to determine if you have the correct pilot installed in your carb. The air screw position determines this for you, making it very simple. If your air screw is less than 1 turn from closed, you need a larger pilot jet. If it is more than 2.5 turns from closed, you need a smaller pilot jet. Once you have determined (and installed it if it's necessary to change it) the correct pilot jet size, and tuned the air screw for the fastest idle, it's time to tune the air screw for the best throttle response. Again, make sure the bike is at full operating temperature. Set the idle back down (the bike should still idle, despite what you read in the Moto Tabloids), and ride the bike, using closed-to-1/4 throttle transitions. Turn the air screw slightly in either direction until you find the point that gives you the best response when cracking the throttle open. Most bikes are sensitive to changes as small as 1/8 of a turn. The air screw is not a set-it-and-leave-it adjustment. You have to constantly re-adjust the air screw to compensate for changing outdoor temps and humidity. An air screw setting that is perfect in the cool morning air will likely be too rich in the heat of the mid-day. Now, it's time to work on the needle. Mark the throttle grip at 1/4 and 3/4 openings. Ride the bike between these two marks. If the bike bogs for a second before responding to throttle, lower the clip (raising the needle) a notch at a time until the engine picks up smoothly. If the bike sputters or sounds rough when giving it throttle, raise the clip (lowering the needle) until it runs cleanly. There isn't really any way to test the needle other than by feel, but it's usually quite obvious when it's right or wrong. Last is the main jet. The main jet affects from 1/2 to full throttle. The easiest way to test it is to do a throttle-chop test. With the bike fully warmed up, find a long straight, and install a fresh plug. Start the engine, and do a full-throttle run down the straight, through all gears. As soon as the bike tops out, pull the clutch in, and kill the engine, coasting to a stop. Remove the plug, and look deep down inside the threads, at the base of the insulator. If it is white or gray, the main is too lean. If it is dark brown or black, the main is too rich. The correct color is a medium-dark mocha brown or tan. Once you have a little bit of experience with jetting changes, and you start to learn the difference in feel between "rich" and "lean", you'll begin to learn, just from the sound of the exhaust and the feel of the power, not only if the bike is running rich or lean, but even which one of the carb circuits is the culprit. Keep in mind, even though this article is intended primarily for two-strokes, four-strokes also need proper jetting to perform right, although they are not quite as fussy as their oil-burning cousins. The only real difference in the two is with the pilot circuit. Two-strokes have an air screw that you screw in to make the jetting richer, and screw out to make the jetting leaner. Four-strokes, on the other hand, have a fuel adjustment screw that you screw in to make the jetting leaner, and out to make it richer." END OF ARTICLE NOTE: REMOVING (leaning) oil from the GAS/OIL mixture makes your AIR/FUEL mixture RICHER, effectively making your engine run RICHER (more smoking/spooge) . If you remove oil from your premix mixture, you have more gas in a specific amount of fuel. Making the mixture that really matters, the air/fuel mixture, richer. Do not fix jetting issues by changing your premix ratio. If you guys like this little article, it would be nice if we could get this stickied in all of the two-stroke forums, to avoid the same questions being asked over and over again. I hope this helps.
  18. Brian Wilson

    JD Jetting Jet Kit

    111 reviews

    James Dean designed the JDJetting kits so that you don't have to be an expert to get professional high performance results!! Even better, technical support is provided. The James Dean custom jetting kit is designed to improve throttle response throughout the range by using specially made multi-taper needles. These are based on the most popular settings used by new generation MX and off-road riders around the globe and the results are impressive. **Exceeds the performance of other standard factory needle options **Low and High altitude custom designed triple taper needles **Main Jets included **Spare Needle Clip **Dyno Tested **Developed and tested from sea level to 12000ft elevation You can’t buy this from any OEM factory or aftermarket.