My introduction - Looking for the right 2-stroke kit

[Miriax]

Howdy everyone!
I'm Miriax, and I hail from Massachusetts, where the terrain is like the weather - all ups and downs.
I've been lurking the forums for a couple weeks now, and I figure I'm overdue for my introduction.
Now, to business!
I have a Trek 4500 2006 or 2007 model that I picked up for $200. It needed new brake and derailer cables, so I fixed those up and gave it a tune-up. See the attached image.
Now that I have a working mountain bike, I want to put a 49cc chain-driven motor on it. The laws in MA are pretty lax about motorized bikes, just that you have to keep them under 49cc and wear a helmet.
I'm probably going to use this as a project bike: put a decent motor on it, get it broken in, and sell it for ~$500. So I want to find a good 49cc kit from a reputable source, for less than $250.
I'm looking at LiveFastMotors, BikeBerry, and Zone8Cycling. These kits in particular:
LiveFastMotors:
http://livefastmotors.com/Gas-Motorized-Bicycle-2-Cycle-40cc-Chain-Drive-Rear-Mount-Motor-Kit.html
Gas Motorized Bicycle 2 Cycle 40cc Chain Drive Rear Mount Motor Kit $225
BikeBerry:
http://www.bikeberry.com/grubee-starfire-48cc-bicycle-engine-kit-epa-certified.html
Grubee SkyHawk Black 48cc Bicycle Engine Kit EPA Certified $210
http://www.bikeberry.com/silver-grubee-skyhawk-48cc-bicycle-engine-angle-fire-kit-epa-cer.html
Grubee SkyHawk Silver 48cc Bicycle Engine Angle Fire Kit EPA Certified $180
Zone8Cycling:
http://www.zone8cycling.com/2010-Grubee-GT5-66cc-Slant-Head-Silver-Finish-p132.html
2010 Grubee GT5 66cc Slant Head (Silver Finish) $180
http://www.zone8cycling.com/Grubee-GT5-48cc-Slant-Head-Silver-Finish-p129.html
Grubee GT5 48cc Slant Head (Silver Finish) $150

So I have a few questions for the ever-helpful denizens of MBc:
If I get a Grubee kit, which I've read are the best bang for the buck, does it matter who I get it from?
Do slant-head kits perform any differently? What's the difference?
Any tips, tricks, or suggestions about the kits or the installation process would be more than welcome.

Thanks all!
~Miriax

 

[DuctTapedGoat]

The big rule of thumb when choosing retailers for the same brand, is knowing the small upgrades they do to the kits.

From the steel sleeve to the bearing on the chain tensioner, there's lots of small upgrades that manufacturers add to their kits over time. Some of the kits that are selling for cheap are older stock inventory that don't have some of these upgrades, so fine print away and be sure you get the best bang for your buck.

Welcome to MBc!

 

[Miriax]

Well, both of the Zone8Cycling kits come with

GRUBEE SkyHawk GT5 48cc [Or 66cc for the other kit] Slant Head Bike Motor Kit (Standard Finish)
1.95 HP [2.75HP for the other kit]. - Speed depends on rear sprocket ratio and weight of rider, weight of bike, the climate and the terrain being ridden.
Friction Clutch, Pedal Start
Magneto With Solid State New Design Capacitive Discharge (CD) Ignition
5 Plate Sprocket Kit
2.5 Liter/0.66 Gallon Fuel Tank, Tear Drop Shape (Black Color)
Push Button Clutch Lever And Cable
Improved Gas Valve
Drive Chain Idler
Chrome Lined Cylinder Wall
202 Crankcase Bearings
Needle Bearings On Piston Wrist Pin

And the Bikeberry kits come with

1. Grubee SkyHawk Angle Fire 2 Cycle 48cc Engine Kit
6. High Quality Japanese Main Bearings
8. Chain Tension Guide
11. CD Ignition Coil
12. Upgraded Alloy Push Clutch Lever
13. Upgraded Twist Throttle and cable with matching grip
15. Black Teardrop Gas Tank (2L)
17. Throttle Cable
19. Gasoline Tank Switch
20. Sprocket Clamp Assembly
21. Sprocket Clamp Bolts
22. Large Spring (Heat Shield Spring)
23. Extension Spring (Recoil Spring)
24. High Quality Needle Bearings on Both Ends Crank
28. Bonus: Sprocket Removal Tool
29. Bonus: Spark Plug Removal Tool

Forgive my noobness, but I took everything out of both descriptions that looked like a difference between the kits and put them in the quotes. I would welcome any help deciphering what the real differences are. Heck, I'd love to be put straight about anything that ISN'T a difference. The more you know, right?
Because of the lack of a descriptive, er, description, I think I'm not considering the LiveFastMotors kit any more.
The description for the BikeBerry kit only highlights the CNS Carburetor, muffler, and fuel line upgrades. The Zone8 kit only highlights the muffler and CNS Caruretor upgrades, but mentions a "EPA approved high-preformance fuel line." All the pictures appear to show the same thing, except for the black finish and the parts being moved around in the pictures a bit. Most of the parts in the kits look like they're the exact same picture and everything!
Thanks for the help! As soon as I'm sure I have my facts straight I'm going to get one of the bad boys.
~Miriax

PS is BikeBerry charging $30 for the black finish, or are the kits more than cosmetically different? They have the exact same description, but the more expensive one is titled an "angle fire kit" and the other is not.

 

[DuctTapedGoat]

Anglefire is really for a frame that can't fit standard motor, so the sparkplug and boot come off to the side so it doesn't hit the top tube.

Black paint is just, well, black paint on the exhaust and motor. I don't recommend them because they run too hot, don't look great after the paint gets cooked, and smells horrid when the paint is being cooked.

There's not really any differences listed, which makes it hard to select. It sucks they don't put a series number on the accessories that come in the kit.

Almost forgot - myself personally, I don't recommend the CNS carbs at all, though the issues are with the version 2 CNS carbs (red cover).

 

[Miriax]

Thanks DTG!
Unfortunately I think all of these kits come with the new carburetor... What're my options for replacing it? And what's wrong with them?

 

[DuctTapedGoat]

I've only done an install with one of them (and I was super upset the client ordered the "upgraded carb" despite me telling him not to). It felt like the choke refused to cooperate, it would only go about 5-10 mph before bogging out. I honestly haven't done the research as far as how to fix what's wrong with them out of the box due to a lack of interest and being upset that they don't work right out of the box.

Options are getting an NT carb, failsafe and work great immediately.

 

[Miriax]

I guess I should mention that I don't know a carburetor from a sandwich.
I am, however, a quick learner.
After looking at Wikipedia, I think I can understand what you mean- the choke valve doesn't close as fully as it should and so the engine becomes flooded by an over-abundance of fuel. Right?
I'm going to deeply enjoy learning how two-stroke engines work. I've always had a penchant for research and learning mechanics.
Thanks!
Any further advice on which of the kits is best for a noob? It looks like all the kits I've considering are highly similar, so now I'm only really looking at two:

http://www.zone8cycling.com/Grubee-GT5-48cc-Slant-Head-Silver-Finish-p129.html
Zone8's Grubee GT5 48cc Slant for $150
http://www.bikeberry.com/silver-grubee-skyhawk-48cc-bicycle-engine-angle-fire-kit-epa-cer.html
BikeBerry's Grubee SkyHawk Silver 48cc Bicycle Engine Angle Fire Kit for $180.

[strike]How bizarre, I can use url tags now.[/strike]
Edit: Do any tags work for me?

Thanks for all the help!
~Miriax

 

[DuctTapedGoat]

That's what I've gathered, like I said, I don't know exactly what's up with them just due to lack of interest and being upset with them.

Looking at them, the only difference is the slant head, they're essentially the same thing. There's a picture graphing out how much space is required in the frame, but I don't recall where it is. The only two qualms I have with the grubees is the CNS carb and catalytic exhaust.

http://www.rawmotors.com/50cc-Bicycle-Engine-Kits/RAW-Silver-50cc-Bicycle-Engine-Kit-p49.html

This is what I run personally, though there's not too many people riding RAW motors. Zone8 used to be a retailer for them, but RAW now sells them themselves individually, so Zone8 is now handling Grubees.

 

[Miriax]

Oh wow, nice find! I wonder why I never saw the RAW kits when I was looking.
It looks like the RAW kit comes with a better chain, throttle, catalytic converter/muffler, and most importantly a non-crappy carb. The only advantages to the other kit (that I can see) would be a bigger gas tank and possibly the sprocket mountings.
Any advice, complaints, anything you've noticed about your RAW kit? At $120, I think that's the way I'm going to go.
Thanks! I think you just saved me a lot of hassle changing out my carb!
~Miriax

 

[DuctTapedGoat]

I really don't have any qualms with mine - regular maintenance has kept mine running as a daily driver for almost a couple years.