mcgradybrandt

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About mcgradybrandt

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  • Location
    British Columbia
  • Interests
    Skiing, Biking, No time for anything else!
  1. I have done the pv mod and switched to a pc2 pipe and the 304 factory sound silencer. The power is smoother and it has more punch which sounds like a contradiction. The bike seems to rev quicker but in a predictable manner. By the time it comes on hard the bike already has enough forward momentum from the boosted low-end. This makes the power seem more linear without the slight hesitation I noticed with the stock pipe right before the hit. The bike definitely pulls second gear better (more like a 300) at low rpm on technical climbs that would normally require a downshift to first gear with the stock pipe unless you are really hard on the clutch. With the pc combo less clutching is required in technical terrain. Mid and bottom are improved with a faster revving feeling, but I think the power on the very top is similar to stock with maybe a bit more authority and less of a flat feeling that I noticed with the stock pipe. The pv mod takes care of the 5/8 - 3/4 throttle annoying stumble that prevents the bike from revving out. I also run a 51 tooth rear sprocket with the stock 14 tooth front, and the yz250 moto head and cdi.
  2. ***the first taper of the Suzuki needles is slightly shallower
  3. I am still trying to understand why some people are saying to go down on the PILOT jet when switching to a Suzuki needle. I agree about the main jet, but totally disagree about the pilot. An N3EW is the same as an NECW on the starting diameter, but the the Suzuki needles have a slightly longer straight section before the first taper of the needle. I also believe that the first taper of the Suzuki needles are slightly shallower than the stock KTM and Yamaha needles (N8RX, N3EX, N3CX etc.) This is backwards thinking to say that a Suzuki needle requires a smaller pilot. Many people also find the Suzuki needles a bit lean at small throttle openings and report a hanging idle or surging especially in cold weather. Generally speaking I run a slightly larger pilot, turn in the airscrew a bit, or turn my idle down when using a Suzuki after switching from a stock Yamaha needle. One of the things I don't like in a 250 with a Suzuki needle is the loss of punch off the bottom when compared to a Yamaha or JD needle since the Suzuki needles are generally a bit leaner up to about 1/8 to 3/16 throttle.
  4. 178 main, N3EW #2, 50 pilot. For normal weather (60- 70 degrees) conditions at sea level, this jetting is way better than what comes stock in any KTM 300 I've ever owned.
  5. If you like the yz cdi try the head as well on the yz250x. They work together like salt and pepper...especially if you do the power valve mod and shave another .012" off the yz 250 head or about .040"-.50" off the stock head.
  6. N3CW #3 will split the difference between N3EW #2 and N3EW #3. The bonus is that the N3CW needle comes free with the bike and it's exactly 1/2 leaner than N3EW in the same clip or a half clip richer if its one clip position lower on the needle. N3EW #2 works great for me in normal riding conditions. I use N3CW #3 in cold weather and N3CW #2 in hot weather. I ride at slightly higher elevation though so you might require N3CW #3 even in warm/ hot weather at your elevation. If you get your head milled it may run better too. I had .012" removed from a stock moto yz head ( not a yz250x head) and it made a big difference. The head shave may not be necessary for sea level though.I have that head and the moto cdi on my 2017 yz250x.
  7. Unless you have done the power valve mod, I doubt I would bother. The stock pv setup makes the bike's motor feel like a big kitten.
  8. Try taking some oil out of the outer chamber. Remove 10ml at a time. I'm only running 280ml in mine with a few face shims removed a couple of the mid-valve shims taken out. I wouldn't want mine any plusher. You might try turning your rebound in a few clicks on your forks and shock to give the bike a more controlled and less busy/ bouncy feel.
  9. 2017 yz250x stock fork springs 280 mm of oil in outer chamber 4 face shims removed (was 11 now 7) 17x .3 and 15x .3 removed from mid-valve compression = 14 rebound = 9-10 rear shock - swapped stock 4.9 for a 5.1 - 26mm free sag and 99mm rider sag low speed compression 14 high speed = 2 turns rebound = 6-7 "A " rider - weight = 185 lbs riding = varies from tight nasty single track to more open flowy single track trails
  10. Amsoil Interceptor is great oil, but it is designed to be run at 50:1, not 32:1 even in a yz250. If you are fast and ride only track, you could try 40:1. Yamalube 2R is not a bad oil, it's just not a synthetic oil like Amsoil Interceptor. A richer (fuel to air) mix of 50:1 will make your bike a bit richer and run cooler than 32:1, but 32:1 does offer a bit more lube for the crank. My crank is always coated in plenty of oil when I change my top-ends at about 100 hrs after running Interceptor at 50:1. Pistons come out clean as can be with minimal wear and have no blow by past the rings. The rings are always still in spec and show no signs of wear to the naked eye. I have never fouled a plug but know a lot guys who keep fouling plugs with Yamalube 2R at 32:1. Kinda sucks having to wait for them to change a plug after they foul it in the first 5 minutes every other ride
  11. N3CW #2 is a half clip leaner than N3EW #2 and N3CW #3 is a half clip richer than N3EW #2. N3EJ is the same as N3EW other than the fact that J is leaner than W on the start section of the needle that controls the flow of fuel in the 1/16 to 1/8 throttle range. Past 1/8 throttle, N3EW and N3EJ are identical when in the same clip position.
  12. My bike seems to run great after a head mod with the stock 178 main and 50 pilot... even in hot weather. I use the1/2 clip stock leaner needle N3CW (in the second clip) that is provided in the kit for that hot weather. I get no surging, detonation or rich blubbering. The N3EW #2 (stock needle) for spring and fall weather works for me and N3CW #3 is good for colder weather. With the RK-Tek head, if I were you, I would go back to the stock jetting as a starting point and tweak it a bit from there. Maybe try 40:1 as well to richen up your fuel mixture a tad. 178 main, N3EW #2, 50 pilot
  13. If you're curious. Try both needles and see which one you prefer. Not a huge difference if you turn your airscrew in a bit with the "J" needle. Just remember to fine tune with the air screw to your liking.
  14. I wonder if heavier aftermarket clutch springs would help?!
  15. You can probably buy it by the gallon and I suspect it will be a bit cheaper than the Amsoil. Yamaha does recommend it for their strokes, not that that is any real surprise, but it may give you peace of mind. I found it worked just fine for a two stroke tranny.