Jump to content


  • Content Count

  • Joined

  • Last visited

About Clark_Mason

  • Rank
    TT Silver Member

Profile Information

  • Location

Recent Profile Visitors

The recent visitors block is disabled and is not being shown to other users.

  1. Clark_Mason

    07 KTM XCF Carb Bog

    Post your specific model of bike, and the current jetting: Pilot jet, needle, clip position, fuel screw setting, main jet, leak jet,any mods; did you test the AC pump after mods? Smoged or de-smoged, exhaust opened up or stock, etc. With additional information constructive suggestions can be made. Cheers Clark
  2. Clark_Mason

    08 KTM 530 excr JD jetting help

    When you were running the 48, DZT-6,180 had the bike been de-smoged and the exhaust opened up yet? When it used to BURN RUBBER and lift the front tire was it de smogged and de restricted? After doing the JD kit install of big O ring cap on the diaphragm standoff - on carb re assembly did you verify the AC pump operation and squirt? The carb comes stock with a 40 leak and normal diaphragm when you install the JD cap on the diaphragm you essentially turn it into a HONDA diaphragm with a longer stand off (a cheaper version of the Honda diaphragm). This cuts off the AC pump operation past approx 1/2 to 5/8 throttle. The large O ring increases the intensity of the pump squirt. So with the small 40 leak and O ring you get good strong squirt on the first half of the throttle opening---should work great. When you open the exhaust the likelihood of popping on decell increases dramatically. Based on your comments you might try RED 4 or 5 vs the Blue 3. If you are anywhere near Valencia, PM me and maybe I can help you out as I stock all the Keihin, Jets, needles, and JD kits. Cheers Clark
  3. Clark_Mason

    average cost of motor rebuild?

    Well I just installed one in a Akro Slip on which was mounted on a 08 530 EXC. These are Akro parts sold through KTM. My 07 has a complete Akro Exhaust and it runs the same spark arrestor as the one in the 08 Akro slip on I just installed. Even though the two cans look a little different the SA was the same 07 complete system to 08 Slip on with the carbon end cap. So chances are pretty good they will fit. The part numbers were obtained from the Akro instruction sheets that came with the systems or slip ones. Other than that I don't have a clue I must be stupid I guess. Cheers Clark
  4. Clark_Mason

    average cost of motor rebuild?

    Akro Spark arrestors: SXS04250518 Spark Arrestor Insert (2004 vintage) SXS07250518 Spark Arrestor Insert (2007 up vintage) You probably need the SXS04250518 check KTM parts. They run about $70US. Cheers Clark
  5. Clark_Mason

    06 KTM 525exc Cooling system flush

    To clean and flush the cooling system make up a mixture of 50/50 white distilled vinegar and distilled water. After draining the old coolant fill with the mixture, start the bike, warm up then stop and let it cool down. Drain the mixture and refill with 100% distilled water, again warm up the bike, let it cool and drain the distilled water. Then fill with the coolant of your choice. The very very mild acidic nature of the distilled vinegar effective cleans the cooling system and will not harm the engine parts, seals, hoses, etc. White distilled vinegar is available at the grocery store along with the distilled water. Cheers Clark
  6. Clark_Mason

    Countershaft Seal leaking

    The biggest culprit in leaking CS are 1) a slacked out spring washer 2) Aftermarket sprockets which are just so slightly thinner than the KTM OEM sprockets and 3) running the drive chain too tight causing high side forces on the CS. Usually it is the spring washer they come with the bolt as a set approx $5US, some have luck just re-shaping the old ones I use new; change it every 1 to 1.5 yrs. Cheers Clark
  7. Clark_Mason

    Do the 450 EXC's have a hour meter?

    As noted above the KTM hour meter incorporated into their Odometer units only activates to rack up hours when the wheel sensor is sending a pulse to the computer. It is close enough for judging maintenance intervals for the majority. Cheers Clark
  8. Clark_Mason

    2005 ktm 525 valve clearence

    Sounds like you do not have the engine at TDC on the compression stroke while doing your adjustment. Cheers Cklark
  9. Clark_Mason

    05 525 oil leak!

    There are machined holes for drilling the oil galleries in the engine case half's that are sealed with an aluminum plugs. One is in the rt case half inboard from the kickstarter inside of the clutch cover you can see the AL plug. sometimes they leak. I usually clean them real good with contact cleaner then with lacquer thinner and then drive them home with a small punch. Clean the area again and then seal with JB weld. Have done two using the above procedure and no more leaks. Cheers Clark
  10. Clark_Mason

    Clutch Hub Nut Torque Spec?

    Was 150NM but KTM lowered it to 120Nm as there was some damage to the split washers which take the torque using the higher 150 number. Cheers Clark
  11. Clark_Mason

    Hicompression piston for 04 450EXC

    I installed a KTM hard parts Hi-compression piston in my 07 450 EXC and it added a very very slight thrust to the bottom end. I would not recommend using this piston as a performance increase unless you have other reasons to be working on the top end like new rings needed cracked piston but cylinder and head still serviceable etc., and for some reason you want to keep it a 450cc bike. If you want more power go for the larger bore as stated above. Cheers Clark
  12. Clark_Mason

    Tire Irons and Black Rims

    Cut up an old plastic gallon water jug and use the plastic as a shield between the iron and the rim. You will soon develop some custom shapes that work good and are cheap to make, all you need is imagination a pair of scissors and the plastic jug. Hum the imagination part might be tough. Cheers Clark
  13. Dave I think you got that backwards the USA 4T's were all Magura until the 07 EXCs which came with the Brembo complete clutch system (ie Master cylinder, lever, clutch line, and a new slave cylinder, etc.). So you have a system of parts that are designed to work with brake fluid and are designed to work with each other (ie piston diameter of the MC and slave, etc). The Brembo slave has a much better bleed set up than the Magura. The 2T's have been running the Brembo set up for the last couple of years so parts should be available. This whole parts situation with KTM right now is pathetic and a real problem for those of us who like to modify and work on these bikes. Cheers Clark
  14. Clark_Mason

    570 ride report

    The 570 Kit is basically a 99mm piston using the stock crank for around 554cc the KTM 540 kit is a 97mm piston which works out at 532cc. While apart you can port do valves, valve springs if needed, change cam grinds, porting, crank lightening, etc. TRAVIS has done more of these than anyone I know of, his shop is located in Pasadena Ca. The price will vary depending on what done. In a 570 Kit Travis can provide stock 11 to 1 or optional 12.5 to 1 compression pistons. He installs a variety of kits and associated cam and porting options so talk with him to decide whats best for your needs. TRAVIS is the real deal. Customers ship TRAVIS motors in cheep inexpensive coolers, properly protected of course, all the time. Cheers Clark
  15. Clark_Mason

    Northern California 525 jetting

    The restrictor in the end cap has been causing a lot of heat related problems in th 07 EXCs. The restrictor empowers the exhaust system to hold much more in the engine and during slow going or riding on a warm day with the lean stock DVR(450) or DVT (525) needles the engine warms way up there. Just removing this restriction really wakes up the bike like 6 to 10 hp and it will run cooler and much better when jetted properly. If you still have the vacuum port on the head hooked up and powering the canister system then a 48PJ would be justified. Cheers Clark