Is that a DTRE carb by any chance? Its your pilot jet that is too small pal thats why it bogs from idle to full throttle and runs better when the air screw is all the way in .It needs atlleast a 25+ pilot jet if its an RE carb . You want it to run with the air screw between (about) 1.1/4 turn to 2.1/4 (some may say different). And you will probably want to drop the the needle to the bottom notch or get a slighty thinner needle . Not too sure on what to advise on jet sizes tho as its got modificatons to the air box and never tryed that myself but a 25 pilot jet may work maybe 27,28 but you would have to try and test these your self. This is kinda just a guideline and may/may not be the right jets you need as its pretty much just trial an error and different bikes can need to be set up different. Read up on 2 stroke carb tuning for some guides some will explain it a lot better than i can.
-- Edited by 1DOWN5UP on Sunday 23rd of June 2013 08:54:41 PM
Im just not sure if the open top air box will upset the jetting but im sure iv read norfe open'd his and said jetting was fine tho so just test them. So yeah put a 25 pilot jet in 3rd notch on the needle an bring the air screw out to about 1.1/4 to 1.1/2ish where it revs nicely with no bogging or hesitasion. Hope this helps
you say if you cover the air box hole it is ok ??? have you changed the air filter and cheack the air box is all tight sealed abd the rubber is fitted ok some times the rubber can pop out between the carb and airbox look insiide to be sure its fitted right . also you got good right size hise clips in place sucking in air either side of the carb can cause problems .. along with air leaks round the power valve
Yeah, try cover up the top of the airbox so much until it's a hole just as big as the original hole, it's probably getting too much air, I'm sure that's the problem
Yeah, try cover up the top of the airbox so much until it's a hole just as big as the original hole, it's probably getting too much air, I'm sure that's the problem
just going on what he says above sounds like he found the problem ? but did not act on it ?
(If i take the seat off and cover the top of the airbox, it seems to rev ok, with no major bogging)
this part bothers me a little what he said ? (The airbox top has been completely removed) do you mean just the snorkle ? or the actual top of the airbox also has anyone done any of the inlet rubber modding cutting away or chamfering to the inside to increse size .
if messing around with the air box breathers or air screw seems to sort it then that is where your problems lay .
wow why would they do that to the air box ? first time I seen that done ? also in that post was that bike ever finish or did it even run that way ? did you also notice he put a 35mm carb on with that airbox ?
a pic of the air box with top cut of .. not snorkel removed but actualy cut the top off ...
I dont get it at all from the air box going from sucking in air throu a small pipe or hole to being wide open ?
if you are running standard carb with standard setup you should definitly cover up the top of the airbox until you have a hole just as big as standard that will most likely solve your problem
yeah can understand now why you would do it but onlu with bigger carb settups .
not sure if the person starting the thread has bigger carb ? or the reason he or some one did this to his bike I would gaffe tape the top up cut a small hole and see how it runs then .
yeah can understand now why you would do it but onlu with bigger carb settups .
not sure if the person starting the thread has bigger carb ? or the reason he or some one did this to his bike I would gaffe tape the top up cut a small hole and see how it runs then .
He said he had 240 main jet, so probably standard carb then
Good idea, tape it over and make a small hole and see how it runs then
