jetting CVTs, plug test
#1
what's the verdict? kill it at full throttle top speed? most load on the motor and see what I get?
I read on one site idle it for 6 minutes and check it to see if you're way rich or way lean
but to me that doesn't make sense as at idle I'd be running on the pilot jet I always thought
ah dunno that's what I was kinda taught at least... stalling it at full throttle with a full load seems to make the most sense.
I set it by ridability yesterday, it was bogging out alot trying to get up to higher revs I had to chop the throttle if u full throttle off idle it'd sputter and stumble alot. so I figured it was too rich. it's a 26 mikuni carb which seems like overkill, but it had a 210 jet so I played with the needle settings and found on the leanest setting (highest clip for needle) it actually sounded alot cleaner on revs (I actually pulled the variator so I could sit still and do full throttle revs to test) and decided to get a couple leaner jets so I picked up a 200 and 190, I put the 200 in and set the needle to the middle and it sounded smoother but I noticed the revs seemed to hang a little and from my experience playing with some 4 strokes it was usually because it was running lean and I had to adjust the air screw which these carbs don't have. So then I got to thinking maybe it's too lean and maybe I should put the 210 back in and try it on the middle needle setting then going lean again with the needle and see if it still hangs again.. but I'm just not sure at this point and figured maybe 2 stokes CVTs or CVT bikes in general have a different method and not a full load stall to check the plug. so I'm just fishing for that info primarily atm
but any other tips would be nice lol.
I don't remember if it had hanging revs before or not so I may switch it back and see. but after fixing an exhaust leak today I noticed I could hear tapping almost like a valve noise and seeing how it's a 2 stroke I decided it couldn't be good so didn't play with it really since lol. I figured it could be pinging/detonation... I think I'll try the 210 jet again or set the 200 to the richest needle setting and experiment with that and see where it takes me. I think I have it on the second lowest needle setting now, as I thought the noise and hanging revs meant lean so tried to fatten it out. But didn't want to put the 210 back in yet as it seemed to run ok.. seems the simplest test would be to put the 210 back in and see if it does hanging revs or noise with the needle in the middle and sputtering
then move it to leaner and see if it does hanging revs... I think I'll also put the head gasket back on. maybe that will be my 1st test, put the head gasket back on and see if the noise and hanging revs are still there... or one stops or both even... then do the 210 w/needle in middle and see. then try needle lean, then try 200 jet... work it systematically kinda. I'll give an update after I play with it a little more
but any advice is welcome
I read on one site idle it for 6 minutes and check it to see if you're way rich or way lean
but to me that doesn't make sense as at idle I'd be running on the pilot jet I always thought
ah dunno that's what I was kinda taught at least... stalling it at full throttle with a full load seems to make the most sense.I set it by ridability yesterday, it was bogging out alot trying to get up to higher revs I had to chop the throttle if u full throttle off idle it'd sputter and stumble alot. so I figured it was too rich. it's a 26 mikuni carb which seems like overkill, but it had a 210 jet so I played with the needle settings and found on the leanest setting (highest clip for needle) it actually sounded alot cleaner on revs (I actually pulled the variator so I could sit still and do full throttle revs to test) and decided to get a couple leaner jets so I picked up a 200 and 190, I put the 200 in and set the needle to the middle and it sounded smoother but I noticed the revs seemed to hang a little and from my experience playing with some 4 strokes it was usually because it was running lean and I had to adjust the air screw which these carbs don't have. So then I got to thinking maybe it's too lean and maybe I should put the 210 back in and try it on the middle needle setting then going lean again with the needle and see if it still hangs again.. but I'm just not sure at this point and figured maybe 2 stokes CVTs or CVT bikes in general have a different method and not a full load stall to check the plug. so I'm just fishing for that info primarily atm
but any other tips would be nice lol.I don't remember if it had hanging revs before or not so I may switch it back and see. but after fixing an exhaust leak today I noticed I could hear tapping almost like a valve noise and seeing how it's a 2 stroke I decided it couldn't be good so didn't play with it really since lol. I figured it could be pinging/detonation... I think I'll try the 210 jet again or set the 200 to the richest needle setting and experiment with that and see where it takes me. I think I have it on the second lowest needle setting now, as I thought the noise and hanging revs meant lean so tried to fatten it out. But didn't want to put the 210 back in yet as it seemed to run ok.. seems the simplest test would be to put the 210 back in and see if it does hanging revs or noise with the needle in the middle and sputtering
then move it to leaner and see if it does hanging revs... I think I'll also put the head gasket back on. maybe that will be my 1st test, put the head gasket back on and see if the noise and hanging revs are still there... or one stops or both even... then do the 210 w/needle in middle and see. then try needle lean, then try 200 jet... work it systematically kinda. I'll give an update after I play with it a little more
but any advice is welcome
#3
I put it on the ground the free rev was to get it not sputtering upon getting up to higher rpm
I put it on the ground but I actually got to thinking, there's a #205 jet so I completely skipped a size by going to the 200.. I'll put the 210 back in, run it on the leanest needle setting and see how it goes. maybe I'll have no tapping noise from that alone. I could've had it the entire time, I just had no exhaust gasket so it would've been hard to tell as there was alot of exhaust leak going on
I put it on the ground but I actually got to thinking, there's a #205 jet so I completely skipped a size by going to the 200.. I'll put the 210 back in, run it on the leanest needle setting and see how it goes. maybe I'll have no tapping noise from that alone. I could've had it the entire time, I just had no exhaust gasket so it would've been hard to tell as there was alot of exhaust leak going on
#4
put the rich jet back in, set the needle to the middle position and put the head gasket back on.
the tapping is still there and the revs still hang and seem to hang more on the leaner jets. I brought it up on the blaster forum and I'm pretty sure it's the pilot jet is too lean. so I'll get a size bigger on the pilot tomorrow possibly and see how it goes.
as for the tapping I never heard it before but I had no exhaust gasket so there was a BAD leak so I don't think I'd of heard it anyway... but I tightened the nuts about as tight as I think it would be good at by hand with a 1/4" socket wrench and still tapping like the head is loose almost sounding... here's a short vid. I don't have a TQ wrench so I'll need to pick up one
LT80tappingnoise.flv video by hawaiianbasshead - Photobucket
the tapping is still there and the revs still hang and seem to hang more on the leaner jets. I brought it up on the blaster forum and I'm pretty sure it's the pilot jet is too lean. so I'll get a size bigger on the pilot tomorrow possibly and see how it goes.
as for the tapping I never heard it before but I had no exhaust gasket so there was a BAD leak so I don't think I'd of heard it anyway... but I tightened the nuts about as tight as I think it would be good at by hand with a 1/4" socket wrench and still tapping like the head is loose almost sounding... here's a short vid. I don't have a TQ wrench so I'll need to pick up one

LT80tappingnoise.flv video by hawaiianbasshead - Photobucket
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