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I'm in New Zealand and the scoot tuning community is non-existant over here, so I need some help please.
I have a Stage6 70cc Racing cylinder kit, the carb I am going to use is a Dellorto PHBG 19mm black racing carb.
Can anyone recommend a main jet size I can start with?
I would assume it would be around the 90 size, but if anyone has experience with these kits, what size main jet should I use as a starting point to tune from.
Good day,If your kit came w/ a #90 jet in the carb. don't assume its correct for engine break-in, if the person that sold you the kit cannot supply you w/ the correct info. START out rich! #130-#140 jet size. I have never seen a new kit sieze from being on the rich side. Break-in and plug check while jetting down to achieve the correct plug color/reading medium to dark brown color on the plug insulator. This is a very vague description of jetting-plug reading, there are many people on this forum that can get you closer and describe it better. I'm sure you will get more posts.
The carb has a 75 jet in it which I'm pretty sure is too small.
my plan was to start around the 130 size and work my way down, But from reading a few posts it sounds like there are people here that know about the Stage6 kits and may have some insight as to an appoximate main jet size that I can use as a staring point.
I'm going to get a few jets and have a play, but I don't want to go buy jets from #80 up to #120, jets are kinda pricey over here and around $7-$10 NZD each.
so the 100-110 is a great start, I'll get some around that range.
why the fuck is everyone recomending jets that are far to big on a 172 let alone a 70.. you lot need to play wiht your rollers. not sure on an aerox engine but a piggy will run around 86 with a filter with the needle second from top, idle mix out 2 and a half ish turns to start with. start at 110 and drop in size. remember poor transmission setup is often overcome by overjetting. hence everyone telling you to use jets that are far too big.
play with the rollers more than the carb at first, once the tranny's setup the carb is a peice of piss. if the other way round you will be at it for days
why the fuck is everyone recomending jets that are far to big on a 172 let alone a 70.. you lot need to play wiht your rollers. not sure on an aerox engine but a piggy will run around 86 with a filter with the needle second from top, idle mix out 2 and a half ish turns to start with. start at 110 and drop in size. remember poor transmission setup is often overcome by overjetting. hence everyone telling you to use jets that are far too big.
play with the rollers more than the carb at first, once the tranny's setup the carb is a peice of piss. if the other way round you will be at it for days
Some good advice there, cheers!
Any idea of what sort of roller weights I should be looking at, I have a rather stiff center and clutch springs, and currently have 4.5g rollers.
imp:
