My 66cc engine is 4-stroking and I believe that getting a smaller jet would fix it. I have a high performance carburetor and the jet size is 78mm. What would be the best size to fix this and where could I get another jet?
Where to buy jets
- Thread starter Carson2000
- Start date
I have a high performance carburetor and the jet size is 78mm.
Without knowing size (5mm or 6mm) you have a couple choices here.
http://www.sickbikeparts.com/catalog/index.php?cPath=22
Without knowing size (5mm or 6mm) you have a couple choices here.
http://www.sickbikeparts.com/catalog/index.php?cPath=22
What is the 5mm or 6mm for. What size is in your carb and what size would reduce this 4 stroking?
The 5mm jets fit the nt carb, the 6mm fit the CNS carb. There might be copies or clones that use them also. I've never bought jets, I solder them up and drill to the size needed. I have had good luck with mine.
There is not a one size fits all when it come to jets, not even on identical engines. I've had some that ran great with a stock jet, some needed soldering and drilled to a smaller size. A couple needed drilling out to get them right. It all depends on the color of the spark plug and the seat of the pants test.
That looks to be as said above Runtong or RT. Auto choke shut off. 5mm thread size. same jets as NT. I've had this carb on 1 bike that ran fine with the stock 70 jet that came with it. I'm at 60 ft above sea level and run 32:1 lucas or amsoil synthetic. I prefer the basic NT with a 66 or 68 jet. Remember this works for me- your results may vary.
A micro drill set is very helpful in tuning a carb, find the bit that fits the jet and mic it, that way you know exactly what size you have.
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Greg do you have a link handy? I know probably been posted before. I do want to try the soldier to size method.
Oh perfect all kinds
http://www.amazon.com/s/ref=nb_sb_s...=micro+drill+bits&sprefix=micro+drill,aps,164
http://www.amazon.com/s/ref=nb_sb_s...=micro+drill+bits&sprefix=micro+drill,aps,164
Mine has the blue drill handle, I was skeptical because of the price but after micing a few they are adequate.
http://bobmay.astronomy.net/misc/drillchart.htm
http://bobmay.astronomy.net/misc/drillchart.htm
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