Needle height 15 bing 70kstar. general bummer

† CH∆D † /

Im having issues with my kit.

1975 puch maxi.s great shape 600 og miles

Stock sprokets

Stock case/crank

70kstar

70highhead

15bing 78jet/needle 2nd from top

foamy high flow

15intake

tecno boss

Ive tensioned my clutch 720* from all the way in.

It runs great on stand.

Checked for air leaks, some minors around carb.

Once I get my weight on the bike she bogs at take off & only makes it up to 30mph. & burning lean?

I cant figure my problem. What needle height should I be at. Its a shorter chubbier needle.

Should I just put an estoril on & forget the boss?

I weigh 165lbs.

Any ideas would be great. Even if my top end is only 35 in the end with the kitt, Im fine with that...but I want some acceleration. Ive been squishing my air filter to choke it to get up to speed.

Thanks

Re: Needle height 15 bing 70kstar. general bummer

you probably have an air leak!

Re: Needle height 15 bing 70kstar. general bummer

advance your timing bub!

Re: Needle height 15 bing 70kstar. general bummer

up jet, if youre choking, which probably means air leak. torque all your shit down, and check again

Re: Needle height 15 bing 70kstar. general bummer

† CH∆D † /

Fully advanced timing. As in rotated stator fully counterclockwise.

Tightened my bolts.

No air leaks.

Boss is still running like shit. Alittle better with the low end, but high end still wussy.

THOUGH.

Put on the estoril & bam. 40mph. Estoril for the newbie tuners it is. Its burning well. Idles like shit though, any tips for that?

Thanks. I still have the 78 jet in.

Enjoi!

Re: Needle height 15 bing 70kstar. general bummer

hey, i've got basically the same set-up except i'm running a 14 bing with a 78 jet... needle 3rd notch from top 32:1 mix... what mix you running? If it's the same I'd imagine you'd need to run at least an 80 jet.

Re: Needle height 15 bing 70kstar. general bummer

have you sprayed carb cleaner on your engine while it is running to check for leaks?

Re: Needle height 15 bing 70kstar. general bummer

78 sounds lean. Find out what the smallest jet is that makes you 4-stroke and then run 2 sizes smaller.

Re: Needle height 15 bing 70kstar. general bummer

really small jet.

some of you dudes are getting really lucky running really small jets in these kits lol

sounds like a lean bog to me.

I dont see how a bing with a 78 could match a 70cc kit and and air leak.

Re: Needle height 15 bing 70kstar. general bummer

† CH∆D † /

yep. No leaks

Re: Needle height 15 bing 70kstar. general bummer

† CH∆D † /

NO AIRLEAK.

Im running 50:1

burning french toast brown.

Re: Needle height 15 bing 70kstar. general bummer

you might be burning french toast brown at WOT, but SOMEWHERE your running lean if squeezing the air cleaner makes it run better.

My guess is you have raised your needle to compensate for the small jet and are getting enough gas at 3/4 but not wot.

you could try setting and resetting your points, but i still think your too lean.

Re: Needle height 15 bing 70kstar. general bummer

† CH∆D † /

hmm. Needle higher lets in more gas. Lower less gas? Correct?

Larger jet lets in more gas

Smaller jet less.

Correct?

My timing is fully advanced. Ill keep working on it.

Though now I have to deal with a rusty gas tank. Did the muriatic acid flush but there is still sediment at the bottom. Take apart the whole bike...gah! Its supposed to be my commuter.

Whats a good way to dry your flushed tank? Im going to seal it this time, but need to be able to dry first.

Thanks

Re: Needle height 15 bing 70kstar. general bummer

ok when talking about needle hight you need to be really specific about raising the NEEDLE or raising the clip, as raising the clip actually means lowering the needle, which makes for less gas....

the lower the needle, the further it sits in the main jet, making the bike leaner.

ignore sediment if its not impeding fuel flow, its chunks that your worried about.

the first tank after you muriatic it is gonna be a little funky anywho, drain all that shit out and just fill it up again. The motion of you riding it stirred it all up

cleaning tanks is what winter is for.

Re: Needle height 15 bing 70kstar. general bummer

so yeah, if you have too small of a main, you could be compensating for it by raising your needle, in which case the bike may run/plugchop right, because the needle is actually in the main jet, but when at wot the needle raises out of the jet for the last bit of throttle the bike is only running on JUST the main and the needle isnt doing anything.

Re: Needle height 15 bing 70kstar. general bummer

definitely upjet man... remember i'm on the 14 bing and can almost make the case to go to an 80... and that's 32:1 mix. If yer gonna stick with that jet you should add more oil to the mix.

Re: Needle height 15 bing 70kstar. general bummer

AHHHHHHHHHh

32:1 is OIL in the premix. More Premix does not make for a richer running bike, it makes it lean actaually. Think about it, more oil in the gas ( which doesnt combust ) so leaner.

Alot of people think this. Stop thinking this.

Re: Needle height 15 bing 70kstar. general bummer

so what's the point of running 32:1 over 50:1?

Re: Needle height 15 bing 70kstar. general bummer

more oiling.

your not gonna sieze your kit by running 32:1, its just more oil. and its prob statistically irrelevant, but anything over 25:1 and you actually can start to displace gas ( this is outboard speak im rattling off, so maybe not the exact same )

May people think they can "richen " thier fuel buy dumping in some more 2 stroke. This is contrary to 2 stroke theory.

The oil is for lubrication. The gas is for cumbustion, Sure some of the oil burns, but alot lubricated things then gets blown out the pipe.

Im just trying to illuminate that more oil does not make a richer gas mixture, nor will it compensate for upjetting.

More oil may make it run cooler, and help lubricate , and 32:1 is def fine for a break in so dont sweat it.

Re: Needle height 15 bing 70kstar. general bummer

so just becuase it smokes more when you pour more oil in the tank doesnt mean its running richer :)

Re: Needle height 15 bing 70kstar. general bummer

Wierd, 70cc treat, HC head, 15bing, 76 jet, no filter, boss pipe tuned clutch netted me 43.6 on a maxi with 16-45 gearing, no porting of the case either.

Re: Needle height 15 bing 70kstar. general bummer

for giggles, take off the air cleaner

Re: Needle height 15 bing 70kstar. general bummer

I really have no idea what actual jet ranges these kits should be in, im just basing my input on the fact that squeezing his airfilter makes the bike run better, and what to me sounds like a lean bog.

even two rebuilt e50's will sometimes have different flow - prob cause one of em leaks a tiny bit ;) or maybe they both do...

Re: Needle height 15 bing 70kstar. general bummer

LEAN.

Re: Needle height 15 bing 70kstar. general bummer

† CH∆D † /

Upjet makes for more gas which is richer? Holy shit I am clueless. Theres some details I havent wrapped my head around.

Ching

Re: Needle height 15 bing 70kstar. general bummer

upjetting means increase the jet size number - like as in put in a jet with a bigger hole....

Re: Needle height 15 bing 70kstar. general bummer

upjet= bigger jet hole=more gas goes through the whole to mix with the same amount of air= richer.

Re: Needle height 15 bing 70kstar. general bummer

dude I may buy that boss off of you if you want to get rid of it.

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