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Re: Where to get a jet kit for Spree NQ50?

Posted: Tue Jul 12, 2016 6:36 pm
by Ultraliner
Jets arrived today. Investigation/testing will commence once weather permits

Re: Where to get a jet kit for Spree NQ50?

Posted: Wed Jul 13, 2016 9:49 pm
by jakubman1
Hey guys. Ive installed my latest bbk. #3... I heat cycled 7 times. a little over kill but whatever. I installed a 90 jet. I ran 30:1 for the first tank for the heat cycles. Now i have 32:1. I have done 2 short trips @ 15mph. I turned my air screw all the way in for this one. My temps are at 266. Everything seems to be going smooth so far.

Re: Where to get a jet kit for Spree NQ50?

Posted: Thu Jul 14, 2016 2:23 am
by Ultraliner
Nice one jakubman! What sort of cht meter are you using? I'm using my multimeter at the mo which is a bit clumsy so am in the market for one

Re: Where to get a jet kit for Spree NQ50?

Posted: Thu Jul 14, 2016 11:13 am
by jakubman1
Trailtec one. The tiny temp one with a 3ft extension wire. Works well. Easy to mount and run the wire. It'll save the.newest hottest temp each time you run it. Like says max temp the it'll.go to your current . Back and.forth.
Least expensive but flimsy wire. Just be careful and you good.

Re: Where to get a jet kit for Spree NQ50?

Posted: Thu Jul 14, 2016 12:01 pm
by Meatball
Last time I seized I had a cht installed. Cruising half throttle for about 10 minutes, the temp range was around 290 and then I tried wot for about 6-7 seconds. I saw it climb to about 330 then it seized. I was watching the temp the entire time. After I pulled over and the engine was off I watched the temp meter KEEP CLIMBING all the way to 385 with the engine off. The cht didn't give me the true temp of the bore/piston to tell me it was dangerously high. Once the bore/piston reaches seize temps, it takes a few critical seconds for those temps to reach the spark plug and reflect to the readout. By then its too late. Its almost like you have to try wot in a short burst then let off and watch the cht for a spike. If you wait for temps to rise before you let off youre too late. It will seize before the cht will tell you to let off.

Re: Where to get a jet kit for Spree NQ50?

Posted: Thu Jul 14, 2016 12:13 pm
by Meatball
This paragraph was copy/pasted from the Jennings book. Its really a good read on how everything needs to play together nicely. I know it was published 40 yrs ago but this guy is a 2-stroke guru. I thought I knew a considerable amount about how these motors operate until I started reading this.

You'll realize, after working with high-output two-stroke engines, that all
of them are to some degree liquid-cooled - and that the cooling liquid is gasoline. It is
true that an over-rich mixture tends to dampen the combustion process, and reduce
power, but here again we find ourselves faced with the necessity for finding a balance
between evils: We have overheating to rob power on one side, and we can cool the
engine with gasoline, but too much fuel also robs power. The solution is a beggar's
choice, in which we try to find the cross-over point between overheating and over-rich
mixtures.

Its on page 33 of the handbook where the "cylinderheads" section begins.
http://amrca.com/tech/tuners.pdf

Re: Where to get a jet kit for Spree NQ50?

Posted: Fri Jul 15, 2016 6:45 am
by jakubman1
My temps went up to 290 going 15mph. Just going up and back the road.

I think I'll be picking up a bigger carb 19mm for the spree. I don't wanna burn another kit.
This is crazy :crazy:

Re: Where to get a jet kit for Spree NQ50?

Posted: Fri Jul 15, 2016 6:52 am
by Ultraliner
Wow... Yeah d*** that is cray cray :*:

Pretty sure if I asked you what size main you are running and how many holes you had in your airbox lid you'd smack me into another forum ;)

Re: Where to get a jet kit for Spree NQ50?

Posted: Fri Jul 15, 2016 8:50 am
by jakubman1
I'm using a 90. 3...1inch holes
The main jet isn't the problem.
Its what Wheelman was referring to. The non exchangeable pilot circuit or whatever.
I think this kit requires a larger carb when you let go of the throttle.
Its not the main but the one underneath the main.

Stock carb can't feed the machine enough gas and it runs lean.
I think imma pick up the 19mm Polini carb from sss.

There's no way around it!! I refuse to drive my spree cause it's just going to overheat.

Re: Where to get a jet kit for Spree NQ50?

Posted: Sat Jul 16, 2016 11:38 am
by Meatball
All the problems Im having with getting these kits to operate happen at wot. Ive made the proper adjustments at all other throttle positions and have gotten it to run at a safe temperature up to about 3/4 throttle. I cant speak for anyone else but my problem is going hot/lean at full throttle. Knowing what we know about mixture adjustments and where they should be made, points to Main Jet.

Re: Where to get a jet kit for Spree NQ50?

Posted: Sat Jul 16, 2016 9:28 pm
by jakubman1
My third kit seize LMAO . Gonna just get the stock kit for 25$ and leave it be.

I guess it wasn't ment to be lol