NC50 Parmakit 70cc

Ronald Covington /

I installed a Parmakit 46mm 70cc cylinder kit with a 4 mm spacer on my 1978 nc50, and I can not get it to start. Fuel is flowing, spark is good, exhaust is not clogged and it ran prior to the kit. Any ideas?

Ron

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Re: NC50 Parmakit 70cc

Brandon Weiss (aka B-Man) /

First, I don't think you'll be able to keep the stock exhaust with the kit.....or at least itd be a good idea to upgrade....

Second, did you rejet the carburetor and upgrade the air filter?

Third, are you sure you installed everything correctly, and in a way that there would be no air leaks? It would be a good idea to do a compression test.

Fourth....BEAUTIFUL BIKE!!!!! Did you go back in time and steal one off the assembly line?Edited 2 time(s). Last edit at 12/08/17 12:55PM by mopedallday.

Re: NC50 Parmakit 70cc

For real - that bike's maybe the best NC I've seen (even sans the horn-cover). Nice seat too. Sorry 'bout your trouble; list out the other upgrades and someone should be able to help. If you've made no other upgrades/adjustments, your carb setting are likely way off.

Re: NC50 Parmakit 70cc

Ronald Covington /

I did not re jet. Could that be it?

I did however, strip it down to the frame, have it repainted, and re-assembled it piece by piece with a new air cleaner. I got the replacement parts from CMS and Ebay.

Re: NC50 Parmakit 70cc

Brandon Weiss (aka B-Man) /

> Ronald Covington Wrote:

> -------------------------------------------------------

> I did not re jet. Could that be it?

>

> I did however, strip it down to the frame, have it repainted, and

> re-assembled it piece by piece with a new air cleaner. I got the

> replacement parts from CMS and Ebay.

That is definitely it. Upgrading you cylinder like that requires supporting modifications. You need more fuel and air to feed it, and it needs to be able to breath freely, instead of through a restrictive stock exhaust.

You need larger jets in the carburetor, and a higher flow air filter at the very least (maybe even a larger carburetor and intake)......

Did you use new gaskets? Did you gap the piston rings? Did you lube everything up internally during assembly? Given that you didnt know you needed to upjet, im curious as to how you installed the kit, and if there may be other problems as well. (just being honest)Edited 1 time(s). Last edit at 12/08/17 01:29PM by mopedallday.

Re: NC50 Parmakit 70cc

^ What Brandon said. Also, you know of the magical land of Treats, yes? I'm partial to Mikuni's, but you'll need to premix if you go that route. Regardless, upjetting, recalibrating, maybe even adjusting the needle will be necessary.

But again, there's lots of little things that might be worth looking into (e.g. gapping the spark plug correctly, checking for air leaks, etc.).

Re: NC50 Parmakit 70cc

I did a write up on installing this kit on nc about 10 years ago. Great kit, will need more carb and pipe though.

Why the spacer? Mine didn't need it, granted I'm sure it was a different production run.

Re: NC50 Parmakit 70cc

Also just noticed your in CO, I'm just north of you in Denver if want to bring it by I can help you trouble shoot and tune it.

Re: NC50 Parmakit 70cc

Ronald Covington /

There is only one ring. I took off the pipe and blew through it. It is about as resistive as blowing through a Hula Hoop. All new gaskets(2) and lubed with synthetic motor oil.

Re: NC50 Parmakit 70cc

Jack Rutherford /

you'll need a bigger idle jet to get that thing to start. You can try turning the idle air screw all the way in for now but that may not get it for you. Right now, I would just leave the stock air filter on for starting purposes. You can switch it later once you get it running. It's been a while since I've looked at a stock nc50 carb. I don't know if that idle jet is removable or not.

Re: NC50 Parmakit 70cc

Ronald Covington /

I will give it shot. Thanks, Ron

Re: NC50 Parmakit 70cc

You said a 4mm spacer was used did it get gasket-ed right? Maybe a vacuum leak.

Re: NC50 Parmakit 70cc

A 4mm spacer regardless is huge. Your compression will also be trash. There is no need for a spacer, why you do dis? Then again, you didn't know you need a jet and your intake and exhaust are going to choke the living hell out of the kit so..

Re: NC50 Parmakit 70cc

Scott Schmidt /

> DPC Ryan Wrote:

> -------------------------------------------------------

> A 4mm spacer regardless is huge. Your compression will also be trash.

> There is no need for a spacer, why you do dis? Then again, you didn't

> know you need a jet and your intake and exhaust are going to choke the

> living hell out of the kit so..

No spacer.

Re: NC50 Parmakit 70cc

i almost garentee the piston is upside down and the window on the piston is lined up with the exhaust port instead of the transfer boost port

Re: NC50 Parmakit 70cc

did you use a spacer to get it to clear that plug on the case?

the spacer is almost certainly your problem, there is no way that can work correctly.

Re: NC50 Parmakit 70cc

Mikey Antonakakis /

> Derek Stahl Wrote:

> -------------------------------------------------------

> Also just noticed your in CO, I'm just north of you in Denver if want to

> bring it by I can help you trouble shoot and tune it.

And I am in the Springs if you feel like driving south!

Re: NC50 Parmakit 70cc

Dude has not come back to this thread in a long enough time. He either fixed it or threw it in a pile.

Re: NC50 Parmakit 70cc

> DPC Ryan Wrote:

> -------------------------------------------------------

> Dude has not come back to this thread in a long enough time. He either

> fixed it or threw it in a pile.

Or maybe he's just caught up in the holiday 'crush' of things ?

Amazingly , some folks do have lives outside of mopeds . lol

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