Kstar specs

There aren't many additions to the Moped Tuners Spreadsheet for 70cc Puch Kstar kits... sooooooo what's everyone's specs?

Right now, mine is:


70 high comp head

19mm phbg (85 main jet, 50 idle - stock set up no tuning done yet)


16x40 gearing

It's hitting roughly 45 right now... but i only have 5ish miles on it, and I'm taking it easy.

I'm curious what everyone else is running for pipes with similar set ups. Thanks!

Re: Kstar specs

E-50 completely re built (crank bearings seals..)

k-star 70

70 hi-comp head

16/16 sha

75 jet

techno estroil de-restricted and stinger cut and welded stright..

well was running 14x36 gearing doin 50.. i put this crazy set up of 18x36 and i hit 51.36 but ran out of road, so we will see when i get it out on the main road...

oh and stock clutch tuned alittle..

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E-50 completely re built and (crank bearings seals..)

k-star 70 case matched

70 hi-comp head

16/16 sha

proma GP pipe

three shoe clutch

76 jet

I'm running 40:1 full synthetic want to switch to 50:1 soon

18 tooth front sprocket

43 mph before i case matched and that was also before rebuid havent done topend test since rebuild, tons and tons of midranged power.

what is stock rear sprocket? im thinking about using a 38 or 42 tooth rear what you guys think?

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i forgot to mention:

case matched

3 shoe clutch w/ blue springs (flush)

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also forgot case matched and cylinder ported, exhaust port widen, intake port matched to intake, boost ports on piston connected to make just 2 big ports rather then 4 little holes..

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would a 21mm PHBG be too much for this kit do you guys think?

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no way !!! do it !! but nothing bigger ..

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i'm just putting in this airsal 70cc i bought last fall. k smart sounds like a winner though

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k-star crank

lightened clutch assembly

k-star 70cc cylinder

70cc hi hi head



95 main jet



alot of porting and tuning went into this build. the bottom end is a little sluggish, but you can get alot of rpm's out of it with some clever porting. by wensday i'll have my cdi on and be retuned, so i'll see how much it takes to blow it up. i have over 600 miles on this setup so far without one seize. pretty impressive for dirt cheap.

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Mine is

Ups magnum


k-star 70cc

19mm phbg 88main,42idl, w9 needle on the leanest setting.

Tecno boss

15x40 gearing.

Does about 50 and I have over 1000 miles on this Daily driver.

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i just took mine around the block the first time since i got the exhaust to seal up feels sluggish kinda, i got the lighnted clutch stuff had blue springs but now im using the ones that came in the three shoe

think this killed some of its kick

what gearing are you guys doing?? mabe we should all update spread sheet ;)

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ALso i think my 16 sha needs a replacement mabe 19 phgb?

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Kstar e50 19mm clone phbg 85 42 2nd needle, proma gp. Matched, 18x40. Blue springs 700 degrees in from flush. Around 50. 200 miles ish, never seized. Ripper for sure bottom and mid are rad. Tops around 50. Oh stock crank and never cracked case too.

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thanks for this list. I am getting ready to do the kstar kit and I am gonna use a 14mm bing will that be enough until the money refills to buy a carb?

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ummm my bike has some awesome low end torque.

still haven't messed around with the carb.. but it sounds like jesse's set up is going to be similar to what i'm going to be running... minus the ups magnum.. which probably adds at least 5 mph for looks alone :)

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I'm thinking of getting the 70cc Treats K-star kit too along with a boss pipe. Is a Bing 15mm going to limit this setup?

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19mm phbg seems pretty ideal to me... I didn't get the 15 mm bing because I was hoping to hit at least mid 40's with some torque. I love bings... theyre super simple... but if you want the most out of the kit, go big or go home seems to be the ideology.

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Griffin Applicable /

gf's maxi


70 head and cylinder

15/15 sha

62 jet

proma gp

pantyhose filter

not matched or ported

stock gearing (16x46?)

i think it must be topping out at or slightly above 40. haven't got a gps or anything. now that the air leaks are fixed it's pretty good off the line. we just put an estoril on it the other day but i've got to up jet a bit for that

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i'm about to do this up...

e50 maxi

stock motor parts

70 head and jug


custom intake/airbox

leovince pipe/home made blaster pipe

modified 2 shoe to start with but i got a $33 treat 3shoe w/ orange springs from mopedshop.com.

timing is all the way advanced,

my buddy was running one with a 16 sha and it sucked he went thu a wide range of jets and air boxes and it either wouldn't idle or would 4stroke at high rpms. definately phbg the thing, we blast at sealevel tho. i'm finding out more and more that low altitudes definately affect whats jets to use.

what kind of base gaskets you guys using, if any, how fat?

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I highly recommend rebuilding cases, people. it's worth it.

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and by cases, i meant engines.

shas are better for novice tuners. phbgs are more difficult to tune.

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Oil ratio's people! Its part of the equation.

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so is timing! :)

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did you rebuild your case and put a aftermarket crank in there?

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dont for get to motor part


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and these


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my Motor

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timo I rebuilt it and put a dmp unstuffed crank in.

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