Is this a good carb?

92gsxbafaro said:
i have an 80cc china motor and im wondering if this is a good carb for the price?

http://www.kingsmotorbikes.com/bike-motor-engine-cns-3p-kit.htm
Click to expand...

Whats wrong with the carb you have now?
Changing carbs will not make your engine faster because it is not the limiting factor.
Get a tuned pipe first.
Tune your engine to take advantage of the improved flow.
Then worry about a "high performance" carb.
(The cns carb is notorious for being very hard to tune correctly anyway)
 
okay i was just wondering it seemed like a good price im not really trying to make it faster just better on gas i figure if you could tune that carb for power you could for fuel efficiency
 
actually the CNS carburetor has been quoted by PirateCycles said it is a mystery carb, untunable, over jeted POS. And they should of "jailed" Grubee himself for bringing that POS into U.S.A.
 
I concur. You'll be better off with the NT or NT 'Speed" carb as opposed to the CNS which is notoriously hard to tune. There is nothing to be gained by changing from what you have to the one you linked to.

I'll have to question as to how many miles you have on your engine. Trying to tune for optimum performance before 200 to 300 miles is futile. Wait until you get some miles on the engine then start with the go-fast parts. Until then you're spitting in the wind trying to make it go faster. An expansion chamber exhaust, smaller rear sprocket and proper carburetor tuning will enhance performance but not until the engine is broken in.

Tom
 
in the pic, they also show an extended manifold - not sure if that comes with the carb, but the one in the pic is the kind that was made by bending the steel rather than welding three pieces together - I don't like these as they tend to have air leaks at the bends and some narrowness that the welded ones don't have
 
i was going to wait till its broken in to do anything to it just buying in advance.. so what would be the best carb and exhaust for fuel efficiency that's all I'm really going for. I know what its like to go fast on a bike and ill stick to 25mph haha i just want good gas mileage.
 
If you want better gas mileage put on a smaller rear sprocket so your rpm's will drop at 25 mph.
How small you can go will depend on how much you weigh, if you need to climb hills and how much you are willing to pedal to help the motor out especially on taking off from a standstill.
 
36t is a nice size to run if you like a cruise speed of 25-30 mph , I weigh just over 210lbs and the 36 works great for me with a well tuned NT or RT Dax carb and a good flowing exhaust, ai have this set up on a stock BGF 66cc engine on my Huffy Karaoke bike, the engine is fairly smooth at 30-32mph but is extremely smooth at 28mph and below, fuel mileage is good, i'd guess 90+mpg maybe closer to 100mpg.

The 32t works great on a 24" wheel also.

Peace Map
 
92gsxbafaro said:
anyone know a good place to get a 36 tooth sprocket for cheap?
Click to expand...

Look at thatsdax.com Duane has a good deal on one $14.99 look on parts page 2.

another choice from BGF on ebay, some say these sprockets are to soft and dont last but I have had great results with them and have not wore one out yet. this come with new coupler and sproket and free shipping for $25.64
http://www.ebay.com/itm/49cc-Motor-...Cycling_Parts_Accessories&hash=item5d4031cbf0

Hope this help you out.

Map
 
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mapbike said:
Look at thatsdax.com Duane has a good deal on one $14.99 look on parts page 2.

another choice from BGF on ebay, some say these sprockets are to soft and dont last but I have had great results with them and have not wore one out yet. this come with new coupler and sproket and free shipping for $25.64
http://www.ebay.com/itm/49cc-Motor-...Cycling_Parts_Accessories&hash=item5d4031cbf0

Hope this help you out.

Map
Click to expand...

I'm currently running a BGF 36 tooth and it is worn out already after only two months. My last stock 44 lasted a year or more. I know there is more stress on a smaller sprocket, but this thing is just junk. It was popping from tooth wear within weeks of installing it.
I will not buy another sprocket from BGF.
Spend the extra and get a decent one from somewhere else.
 
i've used both the rt carb from dax and the mikuni from jakebike, both are good, the rt gave my bike a smoother idle and a bit better performance. the mikuni worked well also, i think the mikuni is more tuneable. as for the sprocket, i just built a bike with a 36 tooth the take off was weak at best but the top speed was great. if you do a lot of stop and go driving then i would not recomend it, if you do a lot of open road cruising then you'll like it. i would used a 41 tooth , i think thats a good compromise between good take off and good speed
 
The mikuni is harder to tune, but generally has better bottom end once you figure it out.
I like the RT for simplicity and easy tuning.
 
lenny9651 said:
i've used both the rt carb from dax and the mikuni from jakebike, both are good, the rt gave my bike a smoother idle and a bit better performance. the mikuni worked well also, i think the mikuni is more tuneable. as for the sprocket, i just built a bike with a 36 tooth the take off was weak at best but the top speed was great. if you do a lot of stop and go driving then i would not recomend it, if you do a lot of open road cruising then you'll like it. i would used a 41 tooth , i think thats a good compromise between good take off and good speed
Click to expand...

I agree that the 41T is a good all around sprocket when a smooth 25mph or maybe a couple more is all you want, easier to start engine and better take off gearing for sure.

I have one RT carb running on a stock BGF 66 slant engine that really performs good, haven't had it on an engine with any mods yet so I'm not sure how it will perform, thinking I may give it a whirl on the Dax balance lower and see what my results are, I would love to get in the 35mph cruise speed area with a top speed of around 40+mph, the stock engine with the RT will top out at close to 40mph probably about 38 and cruise comfortable at 30-32mph, this is with a 36T rear sprocket on a 26" wheel.

after making this post I just remembered that the 36T sprocket on this bike is not a BGF sprocket, its one I made up by drilling the correctly spaced holes in a crank sprocket I cobbed off of a 16" kids bike a couple years ago when I made it so I had forgotten, I do have the 32T BGF sprocket on a bike that is holding up good so far though, but I have to admit it probably only has about 250 miles on it so far.

I need the extra cruise speed because I live so far from town and when I ride to town its a WOT non stop trip of just under 10 miles, I'm thinking about ordering the NG carb that BGF has now also, looks like a Delorto Clone, not sure if it would have any advantage over the RT carb or not.

http://www.ebay.com/itm/310675890788?ssPageName=STRK:MEWAX:IT&_trksid=p3984.m1423.l2649

Thought about building a manifold and seeing if I could get this carb tuned to run good on an HT
http://www.ebay.com/itm/18MM-CARBUR...Parts_Accessories&vxp=mtr&hash=item438e253c6b

Peace, Map
 
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