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About RTTC

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  1. RTTC

    Prime Postion ?

    Its not supposed to
  2. RTTC

    Frame Crack-Pop Sound Again

    I don't know if this is the cause of the sound for other people or not, But the other day I was looking my bike over before a ride and saw a rather large grasshopper laying there dead in the cavity at the back end of the starter just behind the pipe. And when I went to get at it with some long needlenose. I barely touched the heat shield on the pipe and sure enough the shield let out a loud crack like pop that matched the sound that I've gotten before just from touching the bars.. Now I dont know if this is the only source for the mystery sound or not, but i've touched it a couple of times since and i've got it to repeat it (bike hot or cold ) also noticed that it seems to like jump a little even though the bolts are tight
  3. RTTC

    Gear shift bend/height

    This is what my son did to mine and it works great for the size 12berik contender's
  4. RTTC

    650 MPG increased?

    Well when I shimmed- I ground off the side of two washers the right thickness to make them the shape of a D as to fit the recess and level with the shelf , then put a washer on top of the now level surface 0f .028" thickness. also my gearing is 14/42 Air filterss are cleaned alot (since I was 1 that had the sand ingested through the little 1 Bike has 8500 miles now. Been a few thousand since the top end was rebuilt under warranty for that . Oh well, I'm not going to worry about since I've gone through it and every thing looks good:ride:
  5. RTTC

    650 MPG increased?

    06" 650 -snorkel out and needle shimmed,and pilot turned out is what I have.. I did those mods right after purchase at the start of 06 and have been happy with it since except the mpg has always sucked..Right at 38-39 mpg whether in the woods or on street. Well all of a sudden Im getting 42-43mpg and though Im not complaining It has me puzzled??. I thought somehow it had gotten leaned out by way of trash or gunk in the carb but looked and every thing is clean and still like new.I also checked pilot adjust and its right on.SO...Has this happened to any of you, just curious??
  6. RTTC

    Longer shifter, Dr650 06

    I dont think anyone makes one, but this is what my son did on mine and it works with my boots. The problem I had was when standing in rough stuff the shifter would get pushed up and upshift(not good).
  7. RTTC

    pvc fork spacers, what size are you guys using?

    All you have to do is take the caps off and add spacers to whats already there and button it up.When I did mine I cut a set at 15, 20, and 25MM. then try them out and youll find that you dont need very much for most riding, just keep in mind that this is not for big junps just for better handleing. The dr650 jumps like a concrete block with wheels anyway:ride: (What I would give to have some rebound dampning on the rear)
  8. You da Man! Ive followed his posts loosely and this offer may just keep him from the EDGE..I hope he takes you up on it. And I hope it takes care of his problem...
  9. RTTC

    Street Tire Pressure For MT21's?

    I dont know that hard versus soft makes that much of a dif on dot knobs. Harder would make the contact patch smaller so that might make them last a little longer. Im back and forth so much that if I changed the pressure for on then off, thats all Id get done. Btw Im running 18 psi on the rear(cause i use a different front) all the time,Its a good compromise for me
  10. RTTC

    Too Rich?

    Jetting Help Publication Date: 03-20-2006, 12:20 PM You think you did everything right. Bought the most expensive pipe. Paid extra for that jet kit. Followed all the instructions to the letter. If you were lucky, the machine just might actually perform better—except, of course, for that pesky off-idle stumble or the giant flat spot in the mid-range, or how about the severe top end miss (must be the darn rev limiter!). Experience tells me that almost every hop-up anybody has ever done to an ATV has produced at least one point in the rev range that carburetion is considerably worse than stock. Why? Because all you have is a piece of paper that gives you recommended jetting settings. And unless you happen to be lucky enough to ride in those same conditions, there will be some point in the rev range where you will be too rich or too lean. WHAT IS JETTING Jetting is providing the engine with a combustible mixture. The ideal combustible mixture ratio is 14.7 parts of air to one part of fuel, with the most power being produced around 12-13:1. While a motor can (and will) operate on a mixture that is considerably richer or leaner, power output falls off. If you happen to go leaner and ride it hard, you may end up with an over-heated motor, or worse, a seizure. Also be aware that carburetion is measured at throttle position settings. It has nothing to do with engine rpm or transmission gears. So telling the pipe manufacturer or boss that it skips in third. but not fifth gear is totally useless information. Did you know that your fuel pre-mix ratio (two-strokes only!) affects your jetting? A carburetor jet flows X amount of fuel and air at a given time. In that fuel is, say, 32 parts of fuel and 1 part of oil (32:1). If you change your pre-mix ratio to 20 to 1 because you are afraid of burning up your motor, all of a sudden the amount of fuel has been decreased by 37.5 percent. And since it is the fuel and NOT the oil that keeps your ring-ding cool, you run even leaner and hotter! Same theory applies to four-strokes as well; the more fuel entering the engine, the cooler the piston will be. The oil and water cooling systems are not designed to cool the piston; only the little bit of fuel that is mixed with the incoming air charge prevents your motor from seizing. ONLY after the heat has been transferred through the piston to the rings and then to the cylinder, will the cooling system get the chance to do its job. WHY DO I HAVE TO REJET? In a stock engine, the factory has spent a considerable amount of time and money trying various jets and needles to come up with jetting that not only passes the EPA (Environmental Protection Agency) regs, but allows the machine to be operated at roughly factory rated output without overheating and blowing up. When you, as an owner, change anything to do with the intake that would remove factory built-in restrictions to air flow into the engine or, exhaust changes that would do the same for air flow out of the engine, then you will need to re-jet. Why? A carburetor is designed with fixed size main and slow (pilot) jets. The jet needle attached to the bottom of the slide is fixed at a certain height. Only the idle mixture screw is adjustable. If you have increased air flow as outlined above, the increased volume will still be mixed with the same amount of fuel as before, resulting in a lean mixture. If you replace the main jet with a larger numbered jet, the jet’s internal hole will be larger, thus flowing a greater quantity of fuel at 3/4-full throttle. If you raise the position of the slide’s jet needle by lowering the jet needle clip, you are allowing more fuel to rise out of the needle jet at a given part throttle position which is generally 1/4-3/4 open. If you replace the low speed (pilot) jet with a larger numbered jet, the internal hole will be larger, thus flowing more fuel at very small openings of 1/16-1/4 throttle. I STILL FEEL I CAN JET BETTER THAN THE FACTORY CAN Even if you popped for the extra expense of a jetting kit, don’t expect your jetting to be "spot on" unless you are willing to experiment and try different jets. Why? Say you install the main jet the jet kit recommends and it seems to run OK. Is it truly the best for your machine in your riding conditions? It may not be, unless you experiment by going up a jet size at a time until your machine exhibits a stumble at full throttle, indicating a too rich mixture. Then by dropping back one size you can be confident that now you have the correct jet for your machine in your riding conditions. The same thing should also be done with the other fixed jets of your carburetor (jet needle and slow speed pilot jet.). WORKING WITH INDIVIDUAL CARBURETOR CIRCUITS So, how do you start? At the bottom. Then you jump to the top and work your way down. IDLE MIXTURE SCREW: The idle mixture screw is the only externally adjustable carburetor jet available and controls up to 1/8 throttle only. There are two types of idle mixture screws. One type is called a fuel screw because it regulates the flow of fuel into the idle circuit. This type of screw is located ahead of the carb’s slide tower (motor side) and is most often found under the carb’s bore and upside-down directly ahead of the carb’s float bowl. By turning the screw out you increase the amount of fuel that is allowed to slip around the tapered needle and into the carb’s bore where it is mixed with air that has snuck under the carb’s slide. If the idle mixture adjustment screw is located behind the carb’s slide tower (airbox side) then the adjusting needle regulates air flow into a fixed flow of fuel intended for idle. By turning this screw inward you are reducing the air flow, thus richening the idle mixture. When the motor is up to operating temperature, set your idle speed screw to a stable idle. Then use either your idle fuel or air screw to obtain a stable idle. Reset the idle speed screw as necessary after obtaining the correct idle mixture. MAIN JET The main jet controls 3/4-full throttle only. Ideally you should start very rich (large numbered jet) and test at full throttle. It should skip. If not then you are not rich enough! Once you have your rich stumble, back off one size at a time until full throttle operation results in normal operation. (Note: If your ATV runs faster at 3/4 throttle than full throttle you are definitely lean on the main!) JET NEEDLE The slide’s jet needle controls 1/4-3/4 throttle. It does this by passing upward through the needle jet. The needle jet is a long brass tube that contains many small holes in its sides that air passes through. Fuel from the float bowl enters this air stream from the main jet and into the center of the needle jet where it mixes with the air to create an emulsion. This mixture of fuel and air is then metered by the height, taper and diameter of the jet needle as the emulsion passes upward around the jet needle into the carb’s bore where it mixes with still more air to (hopefully) arrive in the motor in a combustible fuel-to-air ratio. If you have a soft hesitation, without a hard stumble, anywhere between 1/4 and 3/4 throttle, chances are your needle is lean, so raise the needle by lowering the clip. Conversely, if you have a hard stumble, chances are the needle position is rich, so lower the needle by raising the clip. If you get very unlucky you might have to start playing with jet needle taper which controls how fast the mixture increases as the jet needle is raised. This would come into play if you were lean at 1/4 throttle, yet rich at 3/4 throttle. The length of the needle comes into play here too. The diameter of the needle controls how much fuel escapes around the needle while still inside the needle jet. The larger the diameter of the straight section or "L" length, the leaner the mixture. Or finally, the "L" length, which controls how much the slide rises before the tapered part of the needle starts. SLIDE CUT-A-WAY The slide cut-a-way controls the amount of air allowed to pass under the slide at 1/8-1/4 throttle. It controls the transition from the low speed (pilot) jet to the main jet-fed needle jet/jet needle. Replacing the slide with one that has a smaller number (less cut-a-way) will decrease the amount of airflow under the slide at 1/8-1/4 throttle openings, thus creating a richer mixture at that throttle opening. If you have a rich condition at 1/8-1/4 throttle and you can’t go any leaner, try a smaller cut-a way. But thankfully, jet needle taper, diameter, "L" length and slide cut-a-way are usually not affected by most simple pipe/air filter modifications. LOW SPEED (PILOT) JET The low speed (pilot) jet controls fuel flow at 1/8-1/4 throttle. The low speed (pilot) jet is usually not affected by most simple pipe/air filter modifications. However, a slightly lean low speed (pilot) jet can raise havoc in the winter where its fuel is added to the total mixture strength required to start. You may find going one level up will help a winter cold start situation. Finally your idle mixture is revisited if you have a deceleration backfire situation. When you chop the throttle and use the motor to decelerate, if you get a stream of backfires, try increasing your idle mixture strength 1/4 turn at a time until the backfire goes away. Note: If you reach a point where your idle mixture is 4 turns out (for fuel type screws, NOT air type screws), try going up one size on the slow speed (pilot) jet and reset your idle mixture screw to 1-1/2 turns out and repeat the process. ONE FINAL NOTE Reading about how to jet will not make you "good" at jetting. And asking someone a thousand miles away why your machine skips in third gear won’t get you the answers you seek. Only hands-on, trial and error experience can solve your jetting problem. So go purchase a handful of jets and get your hands dirty!
  11. RTTC

    2001 silver DR

    Man,this is one sexy color combo to me.I wish this was an option when I got my blue 06 Anyone ever see one of these?
  12. RTTC

    Rectifier ?

    Could someone please tell me what a rectifier actually does. Im tring to work out some probs with the wifes moped( blowing bulbs),the thing is simple to look at cause there aint much there to start with.-Altenator-rectifier- battery- thats it...TIA:blah:
  13. RTTC

    compression release 650???

    I was reading a reply over on ADV rider and it was brought up that the 650 has some sort of release. Ive looked at the manual long and hard but still think this info is Bogus. Does anyone here have any info about this, I dont think it has one but Ive been wrong before...
  14. RTTC

    "poor" gas mileage

    Man, you guys are making me jelous with the kind of mileage your getting. The best ive gotten is around 42mpg with a mostly stock unit,(14t counter,snorkle out,slightly shimmed needle, and pilot out 2). It does stand up on its rear with just a twist of the wrist though..
  15. RTTC

    starter clutch/in or out? DR650

    I'd like to know if there is any difference which way the gear sits in there-Inner/Outer? Recently my ride was in the shop and when I got it back it sounds like the starter is supercharged or something. It starts just fine but did not make the sound before. Makes me wonder what the Boneheads did when they had the cover off to put the new stator in. Any ideas gladly welcomed ..