duggan Posted November 3, 2009 Report Share Posted November 3, 2009 (edited) Hi I have had my 2010 250 2t for a few weeks now and still cant get it to run as crisp as my 09? The carb is set to the standard settings as recommend by beta, 4th needle notch and 1 1/4 turns on the air screw. It seems to be slow to pick up from tick over when the throttle is opened fully, just seems to lack response? Also when revved then the throttle closed it seems to take a while for the rpm to drop back to idle? Anyone found simular or got any ideas? Edited November 3, 2009 by Duggan Quote Link to comment Share on other sites More sharing options...
doogle Posted November 3, 2009 Report Share Posted November 3, 2009 I have a 2010 200 and my mate has a 250, both seem to take a while for the Revs to drop. They both seem to run crisply though. We had Rev 3's before, and they run a lot better than them, but I have never ridden an 09 Evo so can't compare to one of them. Quote Link to comment Share on other sites More sharing options...
duggan Posted November 3, 2009 Author Report Share Posted November 3, 2009 Ah right maybe the revving down slow ain't a problem if they all seem to do it, just couldn't recall if my 09 did the same. Has your friend changed or adjusted anything on his 250? Quote Link to comment Share on other sites More sharing options...
fivemeister Posted November 3, 2009 Report Share Posted November 3, 2009 have a 2010 200 and my mate has a 250, both seem to take a while for the Revs to drop. Flywheel weight! Quote Link to comment Share on other sites More sharing options...
duggan Posted November 3, 2009 Author Report Share Posted November 3, 2009 Flywheel weight! Yeah was thinking flywheel weight, just didn't notice it as much on my 09 which would have had the same weight fitted Quote Link to comment Share on other sites More sharing options...
laser1 Posted November 4, 2009 Report Share Posted November 4, 2009 While it could be a number of factors, I think you should check the air screw. The factory setting is a mere starting point - it is NEVER a static setting on ANY bike. If you just set it per the book - its surely not perfect. Variations from bike to bike - like float level or gas type will require tweaking for proper optimization. Temperature and pressure (altitude) directly effect air denisty, as does humidity, and would obviously effect the air screw setting- If your revs are hanging, it's likely lean on the pilot circuit/air screw. Is it cold out? your engine is getting more air and the proper air screw optimization can make a real difference. The 2nd thing I suggest - especially if the air scew has to be adjusted ALOT and still doesnt totally fix the problem is a air leak - usually around the reed block. Good luck with the new bike - sounds real nice. Quote Link to comment Share on other sites More sharing options...
copemech Posted November 4, 2009 Report Share Posted November 4, 2009 I would ck with the importer to insure you have the proper pilot jet installed in the carb for your local! Too small a jet installed by the factory(emissions reasons) can cause poor pickup and the symptoms you describe. I do not know the preferred settings, yet you would be smart to inquire. Quote Link to comment Share on other sites More sharing options...
nigel dabster Posted November 4, 2009 Report Share Posted November 4, 2009 Take the weight off, I run a 290 like this and its soft as you like off the bottom, two minute job. check the jetting is right, think steve saunders knows what it should be. Quote Link to comment Share on other sites More sharing options...
nigel dabster Posted November 4, 2009 Report Share Posted November 4, 2009 Think the 250 has had some engine changes for the 10, but not sure. Quote Link to comment Share on other sites More sharing options...
duggan Posted November 4, 2009 Author Report Share Posted November 4, 2009 (edited) Have had a good play with the air screw adjusting from anywhere between one turn to two and a half doing 1/8 and 1/4 turns with no real joy, Have dropped the slide needle to the 5th notch from the fourth and it seems to help with the lack of response from idle. will check today for any air leaks around the reed block. Yeah will take the weight of and give that a try also. Edited November 4, 2009 by Duggan Quote Link to comment Share on other sites More sharing options...
laser1 Posted November 4, 2009 Report Share Posted November 4, 2009 Maybe not it, but If you only tried going richer by 1/4 turn from your original setup, I would try going in (less air = richer) some more (at least 1/2 turn in from your original) just to see what happens. 1/4 turn can be hard to notice. 1/2 turn usually obvious to most folks if you dont have other issues. Do you notice any lean bog if you wack the throttle wide open quickly? I usually lower the idle and adjust the AS unitl i can detect a lean bog when quicklt opened full, then go richer by 1/2 to 3/4 turn. I wouldnt take the weight off unless your sure (verify) the jetting is correct. Is there another 2010 you can compare it to? Dealer have one? Have you tried a different batch of gas? Sorry if this AS setting is wasting your time, but have had this work well for several folks. Best regards Quote Link to comment Share on other sites More sharing options...
duggan Posted November 4, 2009 Author Report Share Posted November 4, 2009 Maybe not it, but If you only tried going richer by 1/4 turn from your original setup, I would try going in (less air = richer) some more (at least 1/2 turn in from your original) just to see what happens. 1/4 turn can be hard to notice. 1/2 turn usually obvious to most folks if you dont have other issues. Do you notice any lean bog if you wack the throttle wide open quickly? I usually lower the idle and adjust the AS unitl i can detect a lean bog when quicklt opened full, then go richer by 1/2 to 3/4 turn. I wouldnt take the weight off unless your sure (verify) the jetting is correct. Is there another 2010 you can compare it to? Dealer have one? Have you tried a different batch of gas? Sorry if this AS setting is wasting your time, but have had this work well for several folks. Best regards cheers for your reply and advice, think the lack of response I am picking up on is what you described as lean bog which is most noticable when quickly opening the throttle fully from idle? Sometimes the engine will bog for a second or two then pick up as normal or somtimes it will bogdown and stall. Will have to have another fettle with it tommorrow cheers Quote Link to comment Share on other sites More sharing options...
laser1 Posted November 4, 2009 Report Share Posted November 4, 2009 (edited) Here is a GasGas video (hosted by a fellow TC rider) that shows (with audio) how to setup the air/fuel screw. Note: the carb adjustment procedure that your interested in is about 75% of the way into the video. Also Note: The Dellorto carb on the GasGas utilizes a fuel screw - adjusts the fuel rather than air to the pilot circuit. - Your bike uses an air screw - so your procedure will be backwards - you will need to start with the air screw out (lean) and turn it in (richer). http://d-mis-web.ana.bris.ac.uk/personal/H...adjustments.wmv Tips - I think: Make sure the egine has been completely warmed up - fan has cycled a couple times ect... I always adjust the idle speed to be very low - just above stall. It will change as you get richer (run faster - so readjust it as needed) Give the throttle a very quick, full open spin and release. I use kinda a finger flick. slow is N/G. Its important to let the revs come all the way back down before doing another full throttle wack. Like mentioned in the video - if you need to have the AS at an extreem position, then its time to change the pilot jet. (& make sure its clean) Its good to make sure you can get a definate lean bog and go richer until you cant detect it any more - another half turn richer from that point is usually good. I also find a big hill, rip up the hill (with the engine hot) and chop the throttle at the top. You should not hear any engine detonization or your air screw is too lean still. (Maybe just a "hint" of det is OK if you normally dont ride like that) Edited November 4, 2009 by laser1 Quote Link to comment Share on other sites More sharing options...
duggan Posted November 4, 2009 Author Report Share Posted November 4, 2009 Have been using the same sort of finger flick on the throttle to see how it responds from the idle after completely revving down, sometimes it will rev clean with no bogging and you think you've got it dialed! then a few moment later after another few goes it will bog down and hesitate before revving up? So it seems strange that it fluctuates. Will defo take a sight at that video when am back at my computer tommrrow can't get it to open on me iPhone! Cheers Quote Link to comment Share on other sites More sharing options...
spenser Posted November 5, 2009 Report Share Posted November 5, 2009 We have found a few bikes where the float height was to blame, easy place to start. Spencer Quote Link to comment Share on other sites More sharing options...
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