First build, hopefully fast.

GoldenMotor.com
Dec 11, 2014
628
14
18
Tucson
This is my first build. Starting with a Raw Racer 66cc, billet head, adding an expansion chamber, carb, and doing basic port work. At least getting the transfer ports close to right and matching and enlarging everything, but not messing with timing much. Will be matching the bottom of the piston and lightening it within reason. Going for light and efficient with a 700c fixie style single speed. Plan to run two tanks with regular pre mix then go synthetic 100 to 1 and switch to a 36 tooth rear and a good plug. Here is a pic of the motor mocked up at home and a pic of the bike I just ordered to install it in.

 

BobbyT

Member
Mar 16, 2014
162
15
18
Santa Maria ca.
I recommend you make all your upgrades one at a time after breakin. That way you can see if you have really increased preformance. If there is a problem you will know what it is. Good Luckbrnot
 

max350

Active Member
Apr 10, 2010
322
55
28
Sweden, Örnsköldsvik
This is my first build. Starting with a Raw Racer 66cc, billet head, adding an expansion chamber, carb, and doing basic port work. At least getting the transfer ports close to right and matching and enlarging everything, but not messing with timing much. Will be matching the bottom of the piston and lightening it within reason. Going for light and efficient with a 700c fixie style single speed. Plan to run two tanks with regular pre mix then go synthetic 100 to 1 and switch to a 36 tooth rear and a good plug. Here is a pic of the motor mocked up at home and a pic of the bike I just ordered to install it in.

Why? 100/1. The engine is not designed for it. Does not provide more power, just more trouble :)
 
Dec 11, 2014
628
14
18
Tucson
Have studied oil for decades and the thread in here has pages of people who love it. I am probably going to go 50 to 1 or 80 to 1 though. Looking for maximum lubrication and efficiency. Years of driving RX7's and two strokes growing up so I'm used to pre mix just want to get every last fraction of power out of this one.
 

Flyman

Member
Nov 28, 2014
259
3
18
Vian Oklahoma
I,m by no way going to get in this 100-1 deal again.But no one has answered the
same question ask over & over, as to WHY, & what do you plan to gain?

Anyway I got Fixie running today & will post pic,s tomorrow.

Fly
 
Dec 11, 2014
628
14
18
Tucson
Cool on the fixie, I want to see it! The 100 to 1 is used heavily in commercial applications with great success. They are specific and if not diluted that far do not function properly. They benefits are excellent burn, efficiency, bearing and ring life. But the WHY for me personally is power, second is little to no smoke. I may go with a 50 to 1 synthetic depending on availability. And I am not a synthetic fan, I like dead dinosaurs and smoke but I want this bike efficient and fast so the high tech pre mix wins.
 
Dec 11, 2014
628
14
18
Tucson
Well I got a really nice dremel set for Christmas and got to spend a few hours porting the new motor. I see what people mean about these China girl motors once you have them apart. The intake and exhaust gasket severely restrict the ports and the casting throughout has a bunch of restrictions. I got the stock intake really shaped out well and I was able to machine away enough of the stock pipe to match the gasket which I heard was almost impossible without grinding through it. The bad news thru the whole process is the camera on my phone isn't working so I can't show you all any pics.
 

max350

Active Member
Apr 10, 2010
322
55
28
Sweden, Örnsköldsvik
Cool on the fixie, I want to see it! The 100 to 1 is used heavily in commercial applications with great success. They are specific and if not diluted that far do not function properly. They benefits are excellent burn, efficiency, bearing and ring life. But the WHY for me personally is power, second is little to no smoke. I may go with a 50 to 1 synthetic depending on availability. And I am not a synthetic fan, I like dead dinosaurs and smoke but I want this bike efficient and fast so the high tech pre mix wins.
Good luck with the tuning of the engine :) but the quality of the connecting rod bearing needle bearing is unfortunately pretty bad when it gets a little higher revs , I always use 4% (Although it smokes) to rev up to 10k
 
Dec 11, 2014
628
14
18
Tucson
max350, I am suspect as to that bearing being a weak point as well. I inspected it and it does seem free of any kind of defect. I was thinking of building it with individual needle bearings Porsche style, I wonder if anyone has tried that?
 

KCvale

Well-Known Member
Feb 28, 2010
3,966
57
48
Phoenix,AZ
I,m by no way going to get in this 100-1 deal again.But no one has answered the
same question ask over & over, as to WHY, & what do you plan to gain?
Fly
Oil doesn't combust, gas vapor does, the less oil in the mix the bigger the combustion bang.

If you are blowing blue smoke that is totally wasted power and oil.
 
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Rudz

New Member
Jun 24, 2014
454
1
0
Tyler TX
I've been running 70-1 opti 2 oil for months, broke this new motor in on 70-1 as well, no problem what so ever. I could probably go to 100-1 easily, but I just haven't, it's easier to measure 70-1 because the bottle has the measurement for it
 
Dec 11, 2014
628
14
18
Tucson
My initial plan is to break it in on traditional oil and ratio then switch to one of the synthetics with somewhere from the 50+ to 1 range based on the oils recomendation. Plan to test fit the motor and possibly run it this weekend if all goes well. It is quite cold and raining though, so i hope weather permits.
 

KCvale

Well-Known Member
Feb 28, 2010
3,966
57
48
Phoenix,AZ
I have found 25:1 (5.2 oz 2/3 cup) non-synthetic like Low Ash 2-stroke oil for the first gallon, then go 32:1 (4 oz 1/2 cup) regular synthetic from then on works well, but the optis can be run 80's or more and lube you fine, they cost a lot more.
 
Dec 11, 2014
628
14
18
Tucson
KCvale that sounds like a good break in for sure. I think real fossil based 2 stroke oil is needed to get a proper break in. The new synthetics are literally so good the motor will never break in and you wont be able to get good compression if they are in there from new. And theoretically once you put the synthetic in the motor it will impregnate the metal to a point that you could not go back and try to get it to seat properly later. A lot of molecular level thinking but it has been pretty well established in real world trials.
 
Dec 11, 2014
628
14
18
Tucson
Progress report. Spent some time at two hardware stores. Have almost everything I need except a few motor bolts I was not happy with the matches I found. A quick mock up and I think the motor will squeeze in the frame perfectly. Bough an upgraded U-bolt for the oversize down tube adapter. I know it must be a solid mount but I want to wrap the aluminum down tube to spread the load over a larger area than the U-bolt wrapping around it. I am sure i can come up with something. Will hit an auto parts tomorrow to hopefully find an NGK plug and better plug wire. Been to three places and no decent 2 cycle oil that I trust to break in this motor yet with has been found. Stopped in at a local bike shop for axle nuts and had worked with an employee there about ten year ago and was surprised that everyone was really interested in my motor bicycle build. Will try to get some pics up.
 
Dec 11, 2014
628
14
18
Tucson

Finally have it pretty much assembled. Quite a few small things left to do but might be able to go on a shake down ride this week. Then get her broken in and install the expansion chamber and start tuning for some speed.