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About thedktor

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  1. thedktor

    dr350se wont rev past 4000rpm

    Well, not well explained but I meant the washer that sits on top of the needle and is pushed down by the spring, holding the needle down. It could be the CDI but I would expect it to cut off at the same revs in neutral or in gear? In fact thinking about it I had a similar problem and it was the needle set much too lean, I was convinced it was the stator as it was cutting out like yours like a dodgy spark plug might. CV carbs can behave strangely at times......
  2. thedktor

    dr350se wont rev past 4000rpm

    I would suspect a carb issue from what you have said, either its been put together wrongly, needle loose, missing its spring washer, diaphragm or something. I would like to know if the slide goes up smoothly with a little air resistance, and drops down on its own but with some air damping proving the diaphragm is working correctly.
  3. thedktor

    1997 DR350SE - Carb fuel line routing

    I think some carbs have two "vacuum" type connections, one for the auto fuel tap, one for an oil vapour vent possibly. So the lower right needs blanking as well. The main carb vent is next to the "V" in "Vent", or if that is blanked there is one the other side. A short 6" hose just hangs down.
  4. thedktor

    Shock splash guard-Vortex Airbox

    I have one and thought it was just a standard flap, but will have a look.
  5. thedktor

    DR350se carb question

    Wow that's great news A couple of years ago I resurrected a DR350 and swapped exhaust and carb off another that was running perfectly, and for some reason the resurrected bike ran like crap until I raised the needle 2 clips. Made no sense as the the bikes were identical! Another fix for this lean running problem is a bigger main jet, as on the CV carb main jets have quite an effect lower down in the revs. My current DR, in fact the resurrected one, is more or less standard and I went from a 127 to 132 on another carb I was playing with, for the same issue. Runs well, but any bigger and you start losing power up around the 7-8000rpm range as it gets too rich, and probably even the 132 is too big. Standard airbox with just the snorkel removed. The other thing to consider is that at room temperature 20 deg C or 70 deg F (?) the 350 takes 5 to 10 mins use to properly get up to temperature and any lean issues can disappear once its good n hot.
  6. thedktor

    DR350SE transplant questions

    Like I said earlier - "great job!" Does the 450 kit use the standard crank? Any pics of it, did you have to widen the cases?
  7. thedktor

    DR350 Bogs and Dies as soon as i hit throttle

    Best to get Suzuki parts if you can as some aftermarket o-rings don't have the proper mix of chemicals in the nitrile and either swell up too much or can dry up and shrink when the bike is not used.
  8. thedktor

    DR350 Bottom end in DR350s

    I would check the cam timing is correct, then compare flywheels and pick-up coil positions to see if there is a difference.
  9. thedktor

    DR350se carb question

    Ok that is all good. I can see the needle is quite a lean one ie fat. You could try a very cheap experiment and raise the needle 1-2mm with washers under the clip - I am pretty sure that will help. A needle with grooves has each groove 1mm apart to compare. If you can't find small washers you could make some from some plastic sheet, eg an old oil can.
  10. thedktor

    DR350SE transplant questions

    Wow great job so far. Tell me more about the CDI - is this so you can adjust timing?
  11. thedktor

    DR350se carb question

    Ah you are making us work hard with this one! From your pic it looks like the air jets are correct, the middle one should have a hole about 0.7mm, the right (pilot) should be about a 1mm hole. So, you say you have the white spacer that fits under the needle clip, what about the white spring locator that goes on the other side of the needle clip, on top? We are running out of ideas, next thing is to put a bigger main in, start with a 130. , or raise the needle with a small 1mm thick washer. I have done this with one of mine to fix a similar problem.
  12. thedktor

    DR350se carb question

    OK so its not a question of adjusting the fuel screw so leave that alone for now and make sure all the passages are clear. And I would check the main jet size first as if its too small you will get the same issue. Back to the air jets as per my pic above, the pilot air jet is about 1mm and the main air jet is smaller about 0.7mm, check they are not the wrong way round! They are the opposite size to what you would think logically...
  13. thedktor

    DR350SE transplant questions

    Some back pressure is good, particularly for low and mid-range power. I've done a lot of experiments with different bikes, pipes, and jetting over the years and the results are quite interesting (to me!). Once you reduce silencing to the point where the tone is no longer crisp but more of an unpleasant drone then you lose power in the "usable" range, and sometimes gain a small amount nearer max revs. DB killers are in my experience completely useless devices! Well, they reduce Dbs by restricting flow, ie killing power as well as noise. The best silencers have a certain amount of volume, plus baffles, so the flow is not so much restricted as sent round a few corners and the gas area expanded to reduce noise. Any straight-through pipe does not do this. For example, KTM 4-st silencers use one or two baffles, plus a reasonable volume, plus replaceable wadding and produce a healthy crisp noise and plenty of power. CRD Absolute Performance another good one, The Absolute Power is straight through and too noisy/drony. I have an Arrow silencer on one DR, its OK, perhaps slightly restrictive compared to some but better than stock and not loud by an means. The Supertrap exhaust reduces noise by restricting flow, its a very simple design but not very good if you want power *and* silencing. One of the best exhausts for the DR is one I have that Jesse from Kientec modified to open up the internals and exit hole - its a little louder than stock but not offensive at all, but much more freerer flowing - good power everywhere. That's all, for now
  14. thedktor

    DR350se carb question

    On standard jetting these bikes will run bad if you leave off the airbox side, or chop a hole in the top, so leave all that standard/fitted for now until you have it running properly. Is the diaphragm fitted correctly and not split? What size main jet and pilot?
  15. thedktor

    DR350se carb question

    Typical of being very lean on the needle - have you left out the white plastic spacer that sits under the needle clip? Also did you check the pilot airways were all clear, just blowing air through them won't necessarily clear them. Pilot air jet on the airbox manifold side, - see arrow on pic, its a different carb but same principle. and the middle hole is the main air jet. Blow in the pilot air jet and it needs to come out the pilot jet (in the bowl), the fuel screw (take it out first) and the exit into the carb bore.