"speed" carb upgrade?
- Thread starter DJEEPER
- Start date
i have one on my new bike. i've had three of the old NT carbs, and besides the pink air cleaner and the name "speed," it looks exactly the same.
i haven't torn it apart to see if i could notice a 3mm difference, because i just don't care that much, but it doesn't make my new build go any faster than my old bike.
i can tell you that the square, black NT airbox fits on it, though, because that's what i'm using instead of the fruity lookin' pink one.
i haven't torn it apart to see if i could notice a 3mm difference, because i just don't care that much, but it doesn't make my new build go any faster than my old bike.
i can tell you that the square, black NT airbox fits on it, though, because that's what i'm using instead of the fruity lookin' pink one.
thats' what i figured. they look exactly the same, except the NT's don't say "speed" on them and that stupid pink airbox.
and air filter upgrade i did was drill holes in my plastic box cover looks like swill chesse helps it breahte though thats always good
ive made two changes on my second build it aint tuned in yet but this one has a speed carb my aircleaner is red and will soon be candy green but ive only run the motor arround my parking lot but the differance between flying horse 66 and grubbee 66 is like night and day so far although the grubbee is harder to start but i think that its due to fuel lin issues
the GT5 i have is the easiest to start of all my bikes. i can get on it and push myself 3 feet and it fires right up. still can't "kick start" it 'cause the wheel just stops if it's off the ground.
i've had 3 GT4's that all start different, but have all worked great.
i've had 3 GT4's that all start different, but have all worked great.
For us uneducated what is a GT4 and a GT5 and where do you find that identification when shopping for a motor? I have a Silver Grubee Sky Hawk 66 slant plug motor with the "speed" carb from bikeberry. Without someone here telling me how do you tell the difference between a GT4 and a GT5?
Jim
Jim
GT5 is the newest engine from Grubee. it has a slant head, speed carb with the pink airbox, 8mm head studs, slightly different shaped case, bigger motor mounts to fit newer frames (but not my old standard 1" tubes so i had to re-make mounts) and a few other things.
GT4's have a flat head, 6mm head studs, NT carb with black airbox.
both are 66cc's, and the 5 is supposed to have 2.6hp while the 4 claims 3hp (according to grubee website)
easiest way to tell the difference is the big ugly sticker on the clutch cover. GT5 is a skyhawk and the GT4 is a starfire. it should also say on the metal tag on the clutch rod housing, and failing that, check the side of the box it came in.
(edit) looks like Grubee's coming out with some more stuff, but as far as i know, GT5's are the only ones being imported right now.
GT4's have a flat head, 6mm head studs, NT carb with black airbox.
both are 66cc's, and the 5 is supposed to have 2.6hp while the 4 claims 3hp (according to grubee website)
easiest way to tell the difference is the big ugly sticker on the clutch cover. GT5 is a skyhawk and the GT4 is a starfire. it should also say on the metal tag on the clutch rod housing, and failing that, check the side of the box it came in.
(edit) looks like Grubee's coming out with some more stuff, but as far as i know, GT5's are the only ones being imported right now.
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i cant get mine to run right.... it feels like it is choking and bogging. i have messed with the needle. middle position and one up from that. still no dice with bogging.
plus, it takes a long time for it to start. a good 10 pulls or so where my old one was 2 pulls max.
plus, it takes a long time for it to start. a good 10 pulls or so where my old one was 2 pulls max.
Try the needle in the top groove. These things seem to be set very rich. I run mine in the top groove and have dropped the main jet down to a 68 from the stock 70 and now down to a 66. Even with the clip in the top groove my midrange is still a little too rich.
Jim
Jim
I just got a new GT5 , it feels like a good motor , more power than my 48cc , but I cannot get a good seal at the carb to manifold join , getting tired of taking the carb off and re gooing the join , these carbs are rubbish whatever color the aircleaner is , and theres bugger all difference between them , maybe jets and needles .
Go to a auto parts store or a hardware store and buy a 1/16" stock diameter O-ring that will fit down the opening of the carb where the manifold goes. You will see a step down in the diameter down at the bottom. Get a o-ring that fits snug in the bore against the step. Push the carb against the manifold and compress the o-ring. Hold it tight and tighten the clamp. No more leak. Put the needle clip in the top groove and get a 6.6mm and 6.8mm main jet from Sick bike Parts.com. Depending on what oil mix you run one of those jets should be pretty close. I run Opti-2 at 100-1 and run a 6.6 jet.
Jim
Jim
I tried the O ring , it is a thin one , but it pushes the carb out so the ends of the slots open up, tried to goo them up , the thing is I think its still sucking air because the choke wont kill the motor , and it hunts at idle and has over run when cracking the throttle , Im thinking of getting some silicon tube to slip over the join before the clamp ,
If you have the o-ring properly seated it doesnt matter if the slot is exposed. The end of the manifold is sealed with the o-ring against the step in the carb bore.
Jim
Jim
