motorized pit bike chopper build

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I almost bought this $20 excersize bike, just for that seat!!
 
I have an issue....

Im looking at the mounting pattern on the block of the 212cc predator. I see mounting width of the block is 3-1/8" it just so happens that my lower frame rails, center to center is 3-1/8"

I also have here, the length x width x height specs. Im looking now to find how much the CVT converter adds to the width, to see if i can off set the engine, clear the frame rails, and keep it somewhat center with the cvt added to the width.

Screenshot_2017-02-05-14-13-23_zps14pk5c0b.png


Sent from my SAMSUNG-SM-G530A using Tapatalk
 
I have an issue....

Im looking at the mounting pattern on the block of the 212cc predator. I see mounting width of the block is 3-1/8" it just so happens that my lower frame rails, center to center is 3-1/8"

I also have here, the length x width x height specs. Im looking now to find how much the CVT converter adds to the width, to see if i can off set the engine, clear the frame rails, and keep it somewhat center with the cvt added to the width.

Screenshot_2017-02-05-14-13-23_zps14pk5c0b.png


Sent from my SAMSUNG-SM-G530A using Tapatalk
I don't know the specs of a torque converter off hand but go look up "cars and cameras" on YouTube. For one, it's a pretty entertaining channel that might give you some ideas. But two, they have quite a few builds with torque converters. From what I've seen, it's going to add 5 or 6 inches to one side of the motor. And also, the torque converter placement needs to line up with your chain line more or less. You probably won't be able to do much centering of the motor.

You could get creative with the intake and exhaust on the other side of the motor. I've seen some pretty cool high performance intakes that take up some space kind of the same way a converter does.
 
I don't know the specs of a torque converter off hand but go look up "cars and cameras" on YouTube. For one, it's a pretty entertaining channel that might give you some ideas. But two, they have quite a few builds with torque converters. From what I've seen, it's going to add 5 or 6 inches to one side of the motor. And also, the torque converter placement needs to line up with your chain line more or less. You probably won't be able to do much centering of the motor.

You could get creative with the intake and exhaust on the other side of the motor. I've seen some pretty cool high performance intakes that take up some space kind of the same way a converter does.
Im subscribed... i love their minibikes of death. As for chain alignment, ill have a jackshaft in place. 10t off the converter, 20t jack in, 9t jack out, 19t on stingray hub. It'll be a ratio of 4.22:1 coming out of the cvt. Which means even more reduction off the cvt. So ratio will range from like 6.30:1 - 3.80:1 through the cvt range. Ample.

Motor will be "naked". Custom exhaust, motorcycle tank, airfilter/intake, etc. The only "bulky" part left on the engine will be the pullstart cover itself.
I don't know the specs of a torque converter off hand but go look up "cars and cameras" on YouTube. For one, it's a pretty entertaining channel that might give you some ideas. But two, they have quite a few builds with torque converters. From what I've seen, it's going to add 5 or 6 inches to one side of the motor. And also, the torque converter placement needs to line up with your chain line more or less. You probably won't be able to do much centering of the motor.

You could get creative with the intake and exhaust on the other side of the motor. I've seen some pretty cool high performance intakes that take up some space kind of the same way a converter does.


Sent from my SAMSUNG-SM-G530A using Tapatalk
 
Meaning, i have plenty of room fore and aft in the frame. Centering the engine left to right to miss my bottom frame rails is the quest.

Sent from my SAMSUNG-SM-G530A using Tapatalk
 
If you'd like, I have a tav2 mounted on my go kart engine, and I can get you a measurement when I get home.
 
Yes. That measurement is from the backside of the mounting plate (which would also be the engines mounting surface at the pto), out to the furthest point.

Furthermore, the driver, and subsequently the cover at the driver, is wider than the rest of the torque converter. What this means for you is that the majority of the cover is about 1/2"-3/4" thinner.
If you want to ballance the engine/TC left and right, which point do you calculate the middle from, the widest point, or from the majority? It won't be much of a difference, 1/4"-3/8"; but a don't want you to not have that information.

When I get home tonight, I will give you some more measurements with pics to give you a better idea of what is going on.
 
Yes. That measurement is from the backside of the mounting plate (which would also be the engines mounting surface at the pto), out to the furthest point.

Furthermore, the driver, and subsequently the cover at the driver, is wider than the rest of the torque converter. What this means for you is that the majority of the cover is about 1/2"-3/4" thinner.
If you want to ballance the engine/TC left and right, which point do you calculate the middle from, the widest point, or from the majority? It won't be much of a difference, 1/4"-3/8"; but a don't want you to not have that information.

When I get home tonight, I will give you some more measurements with pics to give you a better idea of what is going on.
Awesome! Thanks.

Yeah, if the CVT adds up to 4.5" onto the total width, then i think i can get away with shifting the engine right to clear the lower frame rails, and it still being center-ish with the CVT added width.

Sent from my SAMSUNG-SM-G530A using Tapatalk
 
I'll also take a length measurment. Since the tav2 would be included into the overall width, maybe the unit could interfere with the frame somehow.

In any case, these measurements should stay steadfast with your motor.
 
I'll also take a length measurment. Since the tav2 would be included into the overall width, maybe the unit could interfere with the frame somehow.

In any case, these measurements should stay steadfast with your motor.
Length isnt an issue, i have about 24" to play with front to back. Check the begining of the thread for pics of the frame.

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Can't get pictures tonight, as the lights are no worky in the garage, atm; but I did get more measurements.

The majority of the cover is 4-1/4" wide, and the entire unit, as measured from the center of the pto to the back, and measured parallel to the engine's mounting surface , is 9-3/4". It barely sticks out past the valve cover on my Subaru engine, which should be pretty darn close to the same size as your Predator.
 


So, i guess the linear twin engines has been done.

Pretty effin cool!!

Sent from my SAMSUNG-SM-G530A using Tapatalk

Dig that bike, stumbled upon it a while back when I searched the web to see if anyone had used a fan case as a fender.
Mustie1 got a new subscriber after I saw that build.
 
Ordered some m8x1.25 coupling nuts last night, along with 1m of m8x1.25 threaded rod. My plan is too lengthen the spring area, to put the lower knuckles in the correct position, when using this OCC 6-3/4" head tube. This bike is on the back burner till i get my sons 80cc bobber wrapped up.
 
Are the welds adequate on the fork?
I think its lazer welded... unless its pressed together. Because i dont see any traces of welding at all, anywhere. Pics coming.


As i wait on parts for my sons 80cc, got this frame up on the bench, and started addressing a stress issue i found with the frame.

Added in a lateral support from the seat post base to the top tube to help take some stresses off the bottom frame rails.

 

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