Inside the 2010 Grubee Skyhawk CNS Carb

[cory151]

I agree these carbs are trash, I did have some better results by bending my float tab. but its like Ive got a hole in the midrange and no real power anywhere. Just for a sanity check I went ahead and rode my 49cc Grubee with the NT carb so I could compare it to the CNS and it was blatant. The smaller motor was much faster and better running, low end, top end and everywhere between.

Ive spent days screwing with this thing and I think spend the $25 on the NT. Even though I paid for a supposed better carb.

 

[BarelyAWake]

An interesting but perhaps unhelpful tidbit is apparently the "CNS" included w/the Grubee kits and the aftermarket upgrade CNS are two completely different carbys, only somewhat similar in construction;

The "YuanDung Skyhawk"

My "Honghua" CNS purchased frm Spooky about 4500 miles ago:

*shrug*

 

[Skarrd]

My "Honghua" CNS purchased frm Spooky about 4500 miles ago:

*shrug*

did that one still used the nylon inserts for the clamp?

 

[BarelyAWake]

Yarp - I've had no trouble w/it tho, I did scuff the intake a bit which helped it grip

 

[Skarrd]

hhmmm, perhaps i should have done that... -derp-

 

[cory151]

Does anyone know if the two idle speed and idle mixture screw could be effecting my mixture at half throttle? If so whats the recommended sequence for setting? By the way the bike runs best at its richest position on the jet (clip set opposite the tip).

 

[BarelyAWake]

No "derp" needed Skarred - not like I was clever or anythin', I had cut & welded the intake to better match the angle of my engine & did a sloppy job grindin' the weld back down, hitting the bit where the carby slides on in my haste - which turned out to be helpful after all heh *shrug*

 

[AzToker]

Nice to see i am not the only one having problems. I can't get it to even idle. It just dies as soon i let go of the throttle. Plus it reqiures more throttle to keep it running. I think i have the throttle handle at least half way to keep it idiling. Both of my screws are totally stuck, i end up stripped the flat head part of the screw. I did try move the clip up n down and no differnces. But i gotta say the new cns intake seals it up good now. I was hoping that it was having a vaccum leak. Nope/ Well i hope u guys get it figured out so i can use it until then i am going to use the speed carb.

 

[Skarrd]

No "derp" needed Skarred - not like I was clever or anythin', I had cut & welded the intake to better match the angle of my engine & did a sloppy job grindin' the weld back down, hitting the bit where the carby slides on in my haste - which turned out to be helpful after all heh *shrug*

well it worked out anyway. i got some jb-weld on mine right now, just took it for a ride after re-building the axle and lining the gear up better. surprisingly ran great. managed to top it out at 33mph, then the fuel bowl went dry need to get a bigger petcock i guess...

 

[biknut]

well it worked out anyway. i got some jb-weld on mine right now, just took it for a ride after re-building the axle and lining the gear up better. surprisingly ran great. managed to top it out at 33mph, then the fuel bowl went dry need to get a bigger petcock i guess...

maybe check the gas tank vent.

 

[PoweredPedals]

Cool, thanks for the info, I updated the pics.

The other kit changes is a heat shield on the tailpipe which for most beach cruisers hits the pedals. Thats OK, it is just two screws to take it off.

The CDI has beefier screw mounts and longer screws that actually fit a fat front tube.

Other than a real gas line, I don't see any other differences.

------

Thanks again on the separate idle system, I know where to look for my problem now.
It idles great but bogs like crazy and soaks the plug when I try to accelerate.

What the heck, since I am messing with it now I'll snap a pic.

-----

This is the carb plunger and lean/rich adjustment.

If I am not mistaken the old carb's only had 3 adjustments and this has 5.
It also looks like it comes set at the second leanest setting (2nd notch from top).

That might explain my bogging problem, not enough fuel with the air.
I'll move it down a couple and see ;-}

The old carby also has 5 adjustments.

 

[oddfellow74]

i have the same issue i have tried everything and it runs terrible

 

[KCvale]

Well, I tried everything we could think of and finally just tossed my hands up and was ready to send the whole carb back to GasBike but figure I'll try this CNS Carb Rebuild Kit for $15 first.

They won't take a carb back once it has had gas in it anyway so I guess we'll see.

 

[cory151]

Well I finally found a solution to this bogging CNS carb bull, and here it is.

YouTube - New Carb

 

[biknut]

LOL so the solution is the old carb?

 

[cory151]

LOL yep its actually a new speed carb Fed Ex just dropped it off yesterday.

 

[biknut]

So how's it run?

 

[Skarrd]

LOL yep its actually a new speed carb Fed Ex just dropped it off yesterday.

where did you order it from? i'm about to contact spooky since i placed an order on friday and havn't even gotten any sort of confirmation if it's been shipped yet...


also how well does that carb stay clamped to the pipe?

 

[cory151]

So how's it run?

Runs great now, I apparently have some chain tweaking to do because i threw my chain within the first 5 minutes of riding this morning then it didnt toss it again for some reason.

 

[cory151]

where did you order it from? i'm about to contact spooky since i placed an order on friday and havn't even gotten any sort of confirmation if it's been shipped yet...


also how well does that carb stay clamped to the pipe?

I ordered it from Spooky Tuesday and got it on Thursday evening. know Im a big quitter for not staying with the CNS, but I feel like I adjusted everything I was able to adjust.

So far the carb seems to stay on great, no issues. I had a ever so slight got yesterday, drop my C-clip down a notch and the thing runs great now. I think I can tell a definite torque difference between the 49cc and the 66cc. The 66c has a little more bottom end.