GT50r - do not do it

GoldenMotor.com

douglasseattle

New Member
Oct 5, 2010
24
0
0
United States
GT50r - (one model below) wait and see

I purchased a model, which is the same motor, but one less horsepower. It is mounted on rear friction drive. My hope to have more power and reliability than the Happy Time motor on my other bike. It failed on both counts. The HT is far better on hills and is more reliable. The first time I rode this I got stalled 15 miles from home - no spark. The spark plug boot has a clip in kind of boot which had fallen apart. I got it going for about a minute then no more.

As for hill climbing and top speed. With my HT motor I have it mounted on a old Univega hybrid bike with a fat tire on the rear. I top just over 40 with a front racing tire from my racing bike. It cilmbs quite well even though it has a 32 sprocket on the back.

The gt50 tops out at 33 on a racing bicycle that is lighter and more aerodynamic. Hill climbing is poor! The motor is smoother however. I am hoping that break in will show dramatic hp improvement. We will see
 
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lowracer

New Member
Oct 17, 2008
1,319
2
0
Charleston, SC
douglassseattle,
Not sure what was wrong with your engine?
I got 2 similar Cag engines off eBay from Zero Pulse USA (Stage 2 Pocket Bike Engines) & they both needed new longer headbolts w/red loctite, copper base head gaskets (replace the paper ones), new spark plug (NGK C7HSA) & wires (using an 7mm automobile plug wire).
Both are equipped with Pocket Bike expansion chamber pipes.
These engines are very powerful & push both my bikes beyond 50 mph. I had a 98cc Lifan 2.5 on one of the bikes prior & this little engine has more go.
Like the china girl engines, they do require attention & tweaking which to me is part of the fun of our hobby.
Sounds to me like you aren't geared correctly. The Pocket bike engine needs a gear reducer to run a 32 tooth. I geared mine w/ 1.5" V-Belt pulley on engine & 22.5" wheel pulley (rim mounted to rim). I tried a 1.75" engine pulley & it wouldn't allow the engine to get into its powerband...Huge difference .25" makes...
-Lowracer-
 

donutguy

New Member
Feb 4, 2010
230
0
0
64
PA
I had a couple of the GT 50r's and I ended up returning them.

I got one of thatsdax's 4 stroke motors......very happy with it.

It's quiet and it has bags of low end torque.

I'm not really to concerned with top speed....as long as I can go 20mph-I'm a happy boy.

It climbs hills like a mountain goat :)
 

donutguy

New Member
Feb 4, 2010
230
0
0
64
PA
I have the newer version of thatdax.com's new 2 stroke. It's still in development.....but I have been using it on and off for the past week weeks. It's a pretty nice piece, but right now I have my new 4 stroker bolted up to my bike.
 

gera229

New Member
Sep 4, 2011
465
0
0
USA
Hey donut guy, you ended up returning the GT50 dax engines? Why?
Did you have the stage 2 kit on them?

The newer one? What's the newer one? Is it the same engine? What's new?
How is it different from the original GT50R engine?

Thanks!
 
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