Simple carb question

Hi i downjetted my 17.5mm carb 1 size and its running worst, dieing after i ease off throttle, shall i go 1 size up from what it was? thanks

 

What was your initial reason for down jetting?

 

would die slightly on full throttle and was producing too much blue smoke.

 

Try upjetting by one size

 

You need to upjet mate, and by quite alot by the sounds of it. Blue smoke means your engine is burning too much oil. indicating there is a lot more oil in an around your engine than there is fuel. meaning your oil/fuel ratio is wrong. in the long run this can cause serious problems with your piston. depending on how long you've been running the bike like this i would upjet it till you get it right and then replace the cylinder and pistons before they pack in. and believe me they are due to pack in if you've been riding it like this

 

recently fitted a 70cc bore mate, its scheduled to go into the garage tomorrow to get tuned on the dyno Ill try upjetting it.

 

Ye if I was you I wouldn't dyno tune it using the current bore, replace the 70 cylinder and piston first or alls your gunna do is spend alot of time fine tuning it on the dyno and then get it out on road and your bores gunna pack in bcos of how its been running

 

think we are a little dramatic here, i understand your advice but i doubt it have damaged anything as there wasnt alot of blue smoke just a little on idle, more than normal but if i had been running it wrong i would of noticed something in the 400 miles i have done on the 70cc...

 

im talking from experience mate not being dramatic. im pretty sure im right in thinking this is the first ped you've tuned, therefor a total newcomer to tuning and to the problems which can occur.
I owned an aerox which went through 4 bore kits in the space of a year all because the mixture was wrong.
Ye the bike may seem ok and run ok on the surface but lets me serious you've not got a camera inside the engine constantly showing you whats going on in there.
and quite clearly you have noticed something wrong in the 400 miles you've done which is the reason for you posting about it and the reason for you needing to change jet size.
In other words mate im trying to give advice based on experience and im trying to help you.
but if you think you no much more than me because you've got your first moped and put a few parts on it then you go ahead and carry on