waiting on my engine

GoldenMotor.com

mr.WFO

New Member
Aug 14, 2010
17
0
0
Texas
having trouble focusing on actual D'ing the W...

so before it gets here & disappoints;
what can you tell me about the engine itself?

i ordered the '10 epa'd grubee 66cc...slant head.
can the head be reversed to ease plug maintenance?
can the jug be reversed to ease carb access?

why do they bill it as a 66cc/80cc?

i've got a pipe almost finished, but still need to flip my bars & fix a fender...

how many of y'all get harassed by the police?
I know some towns are ok with bikes under 50cc, pasadena, TX is not one of them.
however, since i'm riding it to school...they can kiss my ass...

anyone built a happy time v-twin?
twin engine bike anyone?
 

bairdco

a guy who makes cool bikes
Aug 18, 2009
6,537
264
63
living the dream in southern california
grubee's are good engines, usually. i've built 6 bikes with them and i like 'em. haven't had the 2010 model yet, though.

the head can go on either way. there's no performance increase, it's basically designed for clearance.

the barrel can be reversed, but there's some work involved. check my thread on it here: http://motorbicycling.com/f38/backwards-engine-experiment-1939-colson-13458.html

in america, it's a 66cc, in china, they measure funny, so it's an 80. check the Grubee website (ads on the left of the screen) and they explain it.

acme labs is working on a V twin. there's a thread here somewhere, just use the search.

not from texas, so couldn't tell you about the laws there.

i've never used an expansion chamber, but sick bike parts has one, and people seem to like them a lot.

welcome to the forum...
 

poo poo pipe

New Member
Aug 2, 2010
17
0
0
colorado
I got a grubee also like yours last week from king motors bikes,Was impressed on the better casting and finishing on the cases ,some others from diffrent places look rough, got it mounted but need to finalize the cable running and build a tank.
 

mr.WFO

New Member
Aug 14, 2010
17
0
0
Texas
bairdco, awesome writeup on the reversed jug.

i was wondering if anyone has blueprint specs for these motors.

& reading thru 2 stroke performance tuning by graham bell i found this:

In an effort to minimise cylinder and piston distortion, some manufacturers have
chosen to use an offset squish type combustion chamber (FIGURE 2.2). The exhaust
side of a two-stroke cylinder and piston is always the hottest, even though cooling air
flow is much better here than on the back (inlet side) of the engine. There are several
reasons for this, all associated with the passage of very hot (630°C) exhaust gas
through the exhaust port. The escaping gas heats the exhaust port and cylinder wall as
well as the side of the piston. This can cause the piston to expand abnormally and in
some circumstances to seize. To take care of this possibility, the manufacturer may
choose to increase piston to cylinder clearance, but this may not be desirable as extra
clearance can increase leakage past the rings and usually results in high piston wear. A
safer step is to move the combustion chamber to the rear of the head. If this is done,
the front of the piston crown is shielded from the combustion flame by the squish
surface. Then, when the front of the piston is heated during the exhaust stroke, it will
not expand so far due to its being initially much cooler.

did you snap a pic of the inside of the head? i'm getting curious to what a blueprinted/tuned happy time will put out.
 

BarelyAWake

New Member
Jul 21, 2009
7,194
21
0
Maine
Then you may find these of interest;

JE Performance Electronic Ignition and Supercharging

GoKartGuru.com Blog Basic Principles in SuperCharging: A Go Kart With More Bolt On Power

GoKartGuru.com Blog Getting More Umph Out of Your SuperCharger Set Up

Some examples;

Honda CD50 engine in modified Fantic Caballero frame & the Aisin AMR300.


Engelbert Sczygiol designed supercharger for a 50cc two-stroke (1965)

Images from: the bikes

Superchargers small enough to be suited for 50cc engines are rare and far between. You can use a too large charger, but results will not be good.
You have to turn the charger at a lower speed than the engine itself, by reducing the driveratio, sometimes as much as 4:1!

The smog pump - cheap and plentiful. Used on automobile engines since late sixties.
The Aisin AMR300. From Subaru Kei- car - 660cc supercharged citycar.
The KF Max10- 25. American aftermarket blower.
The Hansen V12. Made especially for supercharging Kart- engines from 5- 20hp.
The Busch - used on the Peugeot 125cc Jetforce and Satelis scooters.
from: Supercharging small engines


Keep us informed if you decide to take that plunge into madness :D

brnot
 
Last edited:

BarelyAWake

New Member
Jul 21, 2009
7,194
21
0
Maine
...however I would like to point out that given some of the results of increasing a Chinese 2 stroke's compression - you may wish to consider a different engine, or at least upgrading all of the bearings, the connecting rod & wristpin as well as the head's fasteners... foureasy is quite familiar w/this ;)
 

mr.WFO

New Member
Aug 14, 2010
17
0
0
Texas
thanks, vrry interesting stuff.
this kit is retarded. it would be easier to weld a weed whacker engine to an aluminum bmx frame...with air conditioning.

absolutely nothing 'fits'... onto my second grinding wheel.