Carby what are the advantages /disadvantges of getting the "speed" carb?

[Fletch]

I was using that carb and it was great. I had a HD filter on it from SBP which I don't recommend because it ended up breaking the threads out of the carb (because the screws are so long).

So I took the barrel slide and jet out of the speed carb and put it into the old NT carb. Is this going to be a problem? I haven't ran it to check the plug yet, but the speed carb gets more air as well as having the larger barrel and jet. I think it has a larger air intake as well as the larger air filter. I just used the black NT filter.

Would someone explain to me the different between replacing just the jet and replacing the entire barrel slide? If I'm running too rich, will adjusting the needle work in this case, or do I need to get more air to the carb by maybe opening up the air intake hole?

 

[Chimpo]

motorpsycho,


Do you have a link to the carb that you reviewed?

 

[Fletch]

Sure: http://spookytoothcycles.com/compon...age=vmj_ace.tpl&product_id=441&category_id=93

It's the new NT carb made by Speed.

 

[DuctTapedGoat]

From what I've heard of the differences between NT and NT Speed is that the floatbowl is bigger. The CNS carbs from my experience don't have a stock air/fuel mix screw, but they have two vertical floats. I'm not a fan of the cabled choke either on CNS. I wish I had an NT Speed to compare by hands on with the NT.

 

[Fletch]

I had them side by side today and spent the afternoon turning an NT into an NT Speed. I can tell you the difference now for sure.

The throttle slide is a tiny bit larger on the Speed (won't fit the NT).

The throttle barrel is wider, as is the main jet.

The air intake and output holes are 3mm wider.

I bored out the air intake hole all the way through, and swapped the throttle barrel and main jet from the Speed, as well as the needle which is a little wider and has less of a point. I kept the old throttle slide, and put on the ugly red Speed air filter. I started the engine to see if it would work because I did some other things to the engine, but I didn't ride it.

Tomorrow I'll ride it and see how it is running and if the air/fuel needs to be adjusted.

The bowl might be a tiny bit deeper but I forgot to measure. It's the same width.

I think the CNS is the biggest piece of garbage ever. I wasted so much money on 3 of those and billet intakes. They all broke, and I have a large ziplock freezer bag full of cns carbs and tons of extra parts to them. I'm going to organize everything one day and to take a pic and try to get rid of it all.

 

[TAYLOR MADE]

The bigger carb getes you off the line faster but does not give you more top speed.
It also uses about twice the fuel..
If you have an exp. chamber the bigger carb makes the bike A LOT louder,sounds like a dirt bike...
You can also shorten the 'handel bar mounted clutch leaver' to mount under the seat on the frame ,so there is one less cable running uo to your handle bars

 

[Fletch]

The bigger carb getes you off the line faster but does not give you more top speed.
It also uses about twice the fuel..
If you have an exp. chamber the bigger carb makes the bike A LOT louder,sounds like a dirt bike...
You can also shorten the 'handel bar mounted clutch leaver' to mount under the seat on the frame ,so there is one less cable running uo to your handle bars

The problem is the **** thing vibrates off the intake manifold. The metal they use is really weak. I bought 2 ported intakes for the CNS and 2 different carbs broke off completely where they clamp on the intake. I would avoid the ported billet intakes for the CNS, and if you are going to use a CNS, don't take it on and off a lot. I would ****-near glue the thing on the intake. Blue RTV wasn't strong enough for me. The NT/speed carbs have a smaller output diameter and tighten down on the intake MUCH better. The CNS output is too wide and the carb itself too heavy (the old one's at least- don't know about the new 2nd generation). Add vibration and they brake off or fall off.

 

[DuctTapedGoat]

The red speed cover wouldn't be so bad if it weren't for the fact it just reminds me of the CNS carb.

Well, like I said, I don't have an NT speed, but I was looking at them only last night, and noticed that they were saying that you needed to modify the clutch locker bolt thing on the motor to lower it to compensate for the deeper float bowl. Or correct me if I'm thinking of a different carb, now I'm not absolutely certain!


EDITADD:

2nd gen is still bulky, untunable, heavy garbage.

 

[Fletch]

The only time you need to cut threads on or shorten the clutch bolt is if you use a ported billet intake. I'm guessing that's what you were reading about? There's no way that the bowl is any deeper than a few millimeters (if at all). I'll check tomorrow. It's hardly noticeable if there is a difference. The jet size is the main reason for increased performance. For 25$ it's worth it to me though. If it was just a larger jet I would replace it, but the secondary fuel shutoff and wider throat hole (more air), make it worth it. Plus it seems to fasten on better and has a little clip that helps tighten it down by holding that square nut in place.

 

[DuctTapedGoat]

http://www.piratecycles1.com/pobiin1.html

Ported billet intake, you nailed it.

http://www.piratecycles1.com/raca.html

Got it mixed up with this where it mentions additional clearance needs.

Good call Fletch!!