carb tune and reading plugs

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funfunfk

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Hey every one iam having a few issues getting my tune right
just finished building it with my boys got it off a guy that pulled it apart 18 years ago and sat it in the shed till i got a hold of it

it has stage 7 needles and springs

main is a i think dj 165 in pic

jets on side of slides is a 190

and jets on front are 90

needles are set 2 clips from 2 from blunt end

has major stumble around 5000 and looking at the plugs looking a bit lean (was from a full pull chop) but thinking take the needles to 4 from the blunt end

any advice is welcomed

oh no air box full voodoo 4-2 pipes (really loud it think my neighbors love me now)
 

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You took the bowl off to get the main's?
Plug chop was with a new never run plug?
Awesome pic of the kids!
They ride I hope.
I've got 3 of them! LOL!
 
Some people cut the threads off and read the ring at the base of the porcelain.
 
3rd groove from the blunt end is where most go with stage 7 needles. PJ 2 is a 170 Mikuni stock. I'd change that. V-boost? Filters for the carbs? I'd do a boot inspection all around also.
 
3rd groove from the blunt end is where most go with stage 7 needles. PJ 2 is a 170 Mikuni stock. I'd change that. V-boost? Filters for the carbs? I'd do a boot inspection all around also.

+1..ALSO, go with DJ160's which is equivalent to MK 152. Anything else is really too rich. Needles should be 2nd OR 3rd clip.
 
yeah the boys ride
carbs have been pulled down a few times to get all the settings the same (were all over the place with jets when i first started
no vboost
the spark plugs are new
just seams to miss and fart about at 5000 but not when cold
 

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yeah the boys ride
carbs have been pulled down a few times to get all the settings the same (were all over the place with jets when i first started
no vboost
the spark plugs are new
just seams to miss and fart about at 5000 but not when cold

Rich condition is masked when cold.
 
ok so need go up a clip to closer to the blunt end if i change the pj2 jet to 170 what will that affect ? dose that jet play a part in mid range
 
so switched the clips the wrong way and put 170 in pj2

clips 4 down from blunt end runs really badly at 5 now witch corfirms it need to go to 1 below blunt end will give that a try still think i may be a bit lean in the main still very white on the tip
 
ok so need go up a clip to closer to the blunt end if i change the pj2 jet to 170 what will that affect ? dose that jet play a part in mid range
Paj#2 is the air jet that covers from off idle all the way thru redline.

Sent from my SM-G930R4 using Tapatalk
 
ok sweet have changed the clip to 1 from blunt end runs beuitfuil now and pulls right the way through to 10000 with ease and has plenty of torque everywhere power slides out of corners like a beast cheers for the advice now just got to try and make it a bit quieter now lol oh and since i changed the pj2 plugs have slight brow so happy with that
 
You better get a Dyna ignition box, you need a rev limiter. The engine is not made to be hitting 10,000 rpm. Your engine life will suffer.
 
yeah 1992 rmx 250 like my 2 bangers allso got a t500 titan 1972 classic race bike yeah going to install a rev limiter in to it needs it as it revs out good
 
I have a 1994 RMX250. I'd never part with it, I love that bike. I'm having some way rich running issues at the moment, that I can't quite figure out. Other than that it's never let me down.
 

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