metra kit 65cc help

i built an E50 with Metra 65cc top end, high comp head, kassar crank, clutch tuned in, ported to match top end, techno boss pipe, 15 mm bing, pod filter, with an 89 jet...

started up first kick, hauled ass out the door, then SOFT SEIzed, plug was half brown , half white, so i thought maybe too lean... put in a 92 jet, ran nice, but i could tell it felt like it wanted to soft seize again... too much carb? any ideas would rule, thanks...


acr 512

Re: metra kit 65cc help

not enough carb. There is a reason the intake port on these kits is 19mm. get a dellorto.

Re: metra kit 65cc help

really?! running a 15mm bing and a big ole jet, i would think it would 4 stroke, which would lead me to think more air... so more fuel and more air?! ok, be right back....

Re: metra kit 65cc help

what kinda intake with the dellorto? if the plug is coming out blackish id think itd be ok, but mines a 1st time metra, done some port matched polinis and had good luck with 15 bings and 89 jets.

Re: metra kit 65cc help

a 15 bing will work fine on a metra, just jet it right buddy :)

Re: metra kit 65cc help

thats what i figured, since on all of our polini kits we rock 15 bings... it must be my awesome massive porting demanding so much fuel, come back to austin, see ya in august g money



Re: metra kit 65cc help

Yeah a 15 Bing is plenty enough. I run a 15 Bing on my Metra.

Re: metra kit 65cc help

There is a deifference between "what will work okay" and "what the kit was designed to use." Puch polini's love 19mm carbs too.

Re: metra kit 65cc help

I've seen way more metras seize with 15 bings than with 19 phng. I believe metra reccomends a 19 with the 65 metra, while the polini reccomends a 15 bing.

The 15 will work but it will be more reliable and easily tuned with a 19.

Re: metra kit 65cc help

They rec. the 19.

Its such a perfect match as well, fits right under there. The metra 65 ports are big and that intake is meant for that 19mm delorto.

You didnt sieze your metra cause of that tho, just improper jetting.

Also, when you jammed that crank in did you do seals then check for leaks?

Jetting numbers dont mean shit if your sucking in half the town through your seals.

Re: metra kit 65cc help

You may be over jetted. And have an air leak.

How many base gaskets you running?

Re: metra kit 65cc help

yeah black plug and still ready to soft seize? what oil are you mixing and what ratio...

definitely check into that air leak possibility. out here we run at least 32:1 motul 800 double ester. dont go messing with any of that champion weed wacker stuff. and castrol will foul a plug.

i had that bing and metra set up and it was awight. cracked 50 on it.

what's your gear ratio? also put 3oo miles on that thing before letting it rip...

and that metra will last forever...

Re: metra kit 65cc help

the gaskets that came with metra kits r janky, uneven. it came with 3 metal base gaskets, one paper gaskets.i had to run all of them. when i just ran the one base gasket, the piston hit the head like a piston stop...(high comp 50 cc head, kassar crank)

my rebuild is solid, before i run a new kitted bike out the door, i let it idle for a bit, spray carb cleaner to check for any leaks. etc. working all afternoon just to seize sucks...

i'm waiting on a 19mm, i think it will work awesome, 15mm on this wont be enough, its not regulated with reeds like on a polini, so the blowback fucks with the flow as the piston comes back for the charge.. but what do i know, we'll see. thanks

Re: metra kit 65cc help

I have a 65 kit with a Dellorto 16:16 running an 82 jet and my son said it was soft seizing occasionally. We've been running a 32:1 mix since with no more problems, and the bike hauls butt! (About 48 near as I can reckon).

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