grubee/starfire engines vs raw or any other in frame 2 stroke.

[cspaur13]

is there a difference in them. is the grubee/starfire engines better quality and stuff. i have a raw and ive already seized the crank rod and it messed up the engine after 3 months of riding. it always had a problem 2. so which is better built and better metals.
any help will do. or other posts of the same matter.
thanks,
cody

 

[arceeguy]

For 50cc engines, the Grubee Gen II is the best I've seen. Cast iron sleeve, large bearings, easy pull clutch lever, slant head, flange style carb, roller tensioners, wide frame mounts, and generally nice finish.

The Grubee 50cc GT-2 (chrome plated sleeve) kits come in second, and they are the same cost as the others.

Powerkingshop also sells quality engine kits, don't know which factory they source theirs from though. The Gen II Grubees are NTJL, and the GT-2s are YD.

Worked on a RAW engine last weekend and rank it with Boygofast. Decent engine, but rough finish. (bent fins, rough castings)

Blown engines are usually caused by lean running and/or excessive RPM. The 66cc kits I've sold needed some carb mods to ensure that the mixture was rich enough near top speeds.

 

[biketec]

UMM the GEN-2A engines are NTJL.
Powerking is PiZhou Yong Xing
99% are PYX engines you find anywhere on ebay or other sites.

 

[arceeguy]

I haven't gotten my mitts on the Gen IIa's yet, but if they are as good as the NTJL Gen II's - they are winners in my book!

Are the Boygofast, RAW and Powerkingshop engines all PYX? It does seem like the PKS engines are better than the BGF engines, at least as cosmetics are concerned.

 

[JoelC707]

I might be a little biased because I sell the Star Fire motors only but what the others have said is basically true. Also, the Gen II-A's are generally identical to the Gen II's except they have chromed aluminum sleeves (hence the A on the end). There are some Gen II-A's out there that are 50cc but mine are 58cc. Because mine are a larger displacement I believe they have the same 202 bearings as the GT4, not the larger 203's that the Gen II's have.

Edit: I believe there are only three factories making all the different brand motors. There is the NTJL and PYX that I know of for sure. I'm not positive if the Skyhawk is built in the NTJL factory or not, and if they are who the other factory builds.

Joel

 

[biketec]

I have a list of manufactures and suppliers at work I will post something more later on Monday, But you know what I'd like to do is take my G-2A and race a G-2. Its a long story why our kits dont have steel sleeves but thats not really an important factor in these motors really. What I can say is we have 203 bearings needles top and bottom wider port openings 45 heads lower deck height fantastic castings. Heres a link with some pix in a different thread. http://motoredbikes.com/showthread.php?t=17777 now I know its not really on topic but it has some good pix and illustrates the advancements we are trying to make.