I can breath through it pretty easy.I was thinking too much air not enough fuel,but not for sure.It's the blue low profile ufo style from sick bike parts.Tell me if You think I should try dropping the e clip down a notch on the needle and try it.At this point any ideas?
Carby carb problems now!!
- Thread starter wan37
- Start date
toojung2die
Active Member
Try running the engine without any air filter. With no air filter restriction at all it will run as lean as possible with your present main jet. Don't worry about hurting the engine by sucking in dirt because you will only run it this way long enough for a comparison between stock filter, SBP filter and no filter.
motorpsycho
Active Member
well, if you drop the needle clip down, it will raise the needle, which will richen it up a tad.
I honestly don't see that making a difference tho.
if the filter was allowing too much air, your idle would jump up because it would be running leaner.
if you run it with no filter at all (like the above posts suggests) that will give you the leanest mix possible so you can do a compairison of the 2 filters and no filter.
if the engine runs the same way with the hi-perf filter as it does with no filter, then it's running too lean for that filter.
This MAY require a jet change depending on how drastic it it.
if the new filter is making a drastic difference in the mixture, your idle will be a lot higher than with the stock filter.try to take not of the idle when running it with the stock filter, and then mentally compair it to the idle with the hi-perf filter (or no filter).
I really don't know, because like i said, i put mine on and didnlt have to change a thing.
I honestly don't see that making a difference tho.
if the filter was allowing too much air, your idle would jump up because it would be running leaner.
if you run it with no filter at all (like the above posts suggests) that will give you the leanest mix possible so you can do a compairison of the 2 filters and no filter.
if the engine runs the same way with the hi-perf filter as it does with no filter, then it's running too lean for that filter.
This MAY require a jet change depending on how drastic it it.
if the new filter is making a drastic difference in the mixture, your idle will be a lot higher than with the stock filter.try to take not of the idle when running it with the stock filter, and then mentally compair it to the idle with the hi-perf filter (or no filter).
I really don't know, because like i said, i put mine on and didnlt have to change a thing.
Well this thing is weird, but that's what buying a gurbee skyhawk kit is, plus it's there version of a cns carb.I guess it going to be fun too find the right setting with it.I guess I like to be challenged to fix it....lol
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toojung2die
Active Member
A lot of us don't change jets, though you can buy an assortment of common sizes from SBP. I bought a pin vise with an assortment of drill bits for about $15 at an RC Hobby store. Drop a little piece of rosin core solder in the hole of the jet and melt it carefully with a butane or propane torch. Carefully, because I melted the whole jet once. Then drill out the jet using the chosen bit. I've had to go to a leaner, smaller size on both my engines, a China Girl 66cc and a Yamaha QT50. If the jet is still too rich, solder it up again and drill it out using the next smaller size bit. You can even go larger without the solder. It's a quick and easy way to re-jet for free after you have the tools.
Changing the clip on the throttle slider needle affects mid-range throttle. Idle and wide open remain unaffected. Adjust the jet for wide open throttle first.
Clean carbs and jets using aerosol carb cleaner. Wear safety glasses! That stuff sprays back and it'll burn your eyes really bad.
(personal experience
)
Changing the clip on the throttle slider needle affects mid-range throttle. Idle and wide open remain unaffected. Adjust the jet for wide open throttle first.
Clean carbs and jets using aerosol carb cleaner. Wear safety glasses! That stuff sprays back and it'll burn your eyes really bad.
(personal experience
)
toojung2die
Active Member
Maybe this will help: http://www.csgnetwork.com/drillsizeconvert.html
There is no .68mm size on this chart. There is a 68 wire gauge. The mm sizes are in half increments; .60mm .65mm .70mm etc...
I go by .000" since that's what my dial calipers measure and there's a lot more bit sizes using that scale. My experience is the jet size is not terribly critical. My bits are matched to the wire gauges and going one size smaller than stock always had the desired results.
If I was buying jets I would get one the next larger size and two the next sizes smaller. I think stock jets tend to run rich because you can't burn up an engine by running too rich. Fouled spark-plugs and four-stroking are the result of rich jets.
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I'm just going by the grubee size it say stock is .068mm my bad.I read some where on one of these forums.That I have to oil the filter so it restrict the air flow. I will try that and let you guys know if it help my problem.Here's a link that I found and it sums up the answers here just like motorpsycho said jet drilling.I'm on the same page on drilling toojung2die.
http://motorbicycling.com/f13/anyone-heard-too-much-air-cns-33511.html
http://motorbicycling.com/f13/anyone-heard-too-much-air-cns-33511.html
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HeadSmess
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when drilling jets for that "perfect" size, yes, theres the wire guage/numbered/imperial (thou) sizes that can often be in between the metrics, or...
when soldering the jet and redrilling, bear in mind the LENGTH of hole can also control fuel flow... so by filling the jet up with more solder, which increases how long the hole is, you can fine tune a certain size hole.
ie, i go too lean on a .45, i start 4 stroking on a .5. but if i fill the jet with solder halfway then drill it at .5, its now flowing somewhere in between the two and poifect
you can also tweak mixtures with the oil ratio, and fuel level.
noone can really recomend the ideal size for you because they ARENT you! this is what plug chops are for! you need to tune the engine in for yourself! sorry... but altitude, oil, oil ratio, fuel... it all plays a part in jetting.
when soldering the jet and redrilling, bear in mind the LENGTH of hole can also control fuel flow... so by filling the jet up with more solder, which increases how long the hole is, you can fine tune a certain size hole.
ie, i go too lean on a .45, i start 4 stroking on a .5. but if i fill the jet with solder halfway then drill it at .5, its now flowing somewhere in between the two and poifect
you can also tweak mixtures with the oil ratio, and fuel level.
noone can really recomend the ideal size for you because they ARENT you!
this is what plug chops are for! you need to tune the engine in for yourself! sorry... but altitude, oil, oil ratio, fuel... it all plays a part in jetting.Similar threads
Engine Trouble
Bogs off over 5mph; operating @ idle speed.
