212 predator build

[Amarion1]

So it was a toss up between the 79 and the 212 and I figured they're so close in physical size that I'd go with more power. Don't need to use it but its there if its needed. I want my bike to do 50MPH without hesitation and have good acceleration off the line but I don't plan on taking it over 40 =-)

This is going to be a slow build and I'm hoping to get it done for the summer and my funding is coming from donating plasma which is $200 a month

I have a frame but its a tad bit small and I can't afford a new frame so I will lengthen it where I need it to fit this engine with a little room to remove the valve cover (good idea came from scotto's build)

I bought the engine and removed the governor and oil sensor. Need to order a billet flywheel and piston connecting rod

Is it reccomended to upgrade the cam and springs as well? Any advice is greatly appreciated

Still need:

Front suspension fork
Front hydrolic moped disc brake set up
Either rear vbrakes or disc on a jackshaft or both?!
Transmission system of some sort
Jackshaft
11 guage spokes
HD rear hub
Front disc hub
Wide pedal crank set up
Engine mounting set up
Throttle set up
22mm mikuni carb and filter
Fuel tank
Tach/hour meter

First i'm building the engine and working the frame to fit it. Then I will work on the wheels followed by a new fork and hook up the brakes. Last will be the transmission system / jackshaft. I'm ordering parts mostly in that order. And maybe the small extras when I get extra money

I'm all about safe stopping and a strong frame!

So I'm super stupid when it comes to numbers and gearing and all that good stuff. I just don't get it... I try but it doesn't click

So my biggest problem (besides engine internals) is a transmission set up. I can build my mounting plate to the motor and a jackshaft but I don't understand the gearing for what I want to do. Like a drive sprocket to centrifugal clutch to sprocket to jackshaft sprocket to rear sprocket....

Or I could buy the gasbike trans that they sell for this engine and adapt that to my jackshaft to the rear sprocket but I still don't know the right size gears to use on my jackshaft and rear wheel sprocket

I wanted a qmatic tranny but not 100% sure it will fit the 3/4" drive shaft. And then again there's the jackshaft to rear gearing I need help with

I like the small size of the qmatic to keep the entire set up thinner than wider

Again. I'm looking for good acceleration with little or no pedaling and a top speed of 50 so I can cruise nice at 35-40

I need help! Please and thank you! I will post pics along the way as I go but its gonna be a long ride before the first ride!

I love critisism and feedback and ideas of all kind!

Thanks all!

 

[Amarion1]

Oh!

What kind of HP will this engine put out with these mods?

No governor
Billet flywheel
Billet piston connecting rod
Cam and 18# springs (or are heavier springs better?)
22mm mikuni carb
Open but longish exhaust

Thank you =-)

 

[MotoMagz]

10 -13hp is what I've read. I just did flywheel timing ,carb. and govner . Not doing anything internal besides govner. I think I would rather have the valves float than break a rod. But lots of people replace spring and not rod with good results . There are guys on here with way more knowledge on the 212 then me just throwing on my 2 cents.....good luck

 

[Amarion1]

Thanks for the info!

Still researching and planning! Ordered a Huffy Millennial 29er last night. Checked it out in store and the steel is the same gauge as my current bike that would have needed chopped forward and taller. Will most likely put a few extra welds on it and I've got a solid steel rod that's going inside the seat tube for added strength

I don't know whether to run the 29er wheels or go with 26's. Any recommendations? Either way I need to spoke it heavier and change axles. I loved my last 29er build and my 700c was wonderful but 26's have better tire selection.. otherwise I will wait and build my jackshaft and see how each size wheel/tire fit with it.

 

[Amarion1]

A couple updates although nothing exciting

Received Huffy Millennial 29er bike! Comes stock with 10 gauge spokes too! Don't know if I can use them with the Grubee HD hub I just ordered but I'll find out here soonish! Also received 2 pillow block bearings for the jackshaft. Aaannnndddd I just ordered a keyed shaft, throttle handle/cable, 24 tooth sprocket and adaptor for JS, and another adapter for JS disc brake. Also received the motor mounting plate kit but the brackets wouldn't adjust for the angle I'm mounting at so I ground them to work but its a bit choppy so instead I'm going to buy a couple exhaust clamps to weld to the plate at the proper angle. Slow going but she'll get there

 

[MotoMagz]

Sounds like some good xmas shopping! 10 gauge spokes are 3.05mm ...11 gauge 2.9 mm...12 gauge 2.6 mm most likely they are 12g. That's the largest found on off the shelf bikes. But please measure the diameter of the spokes cuz if there 10g I'm getting some!!!

 

[Amarion1]

Awe what a slap in the face . I measured .102 inches and checked the gauge chart at work and got 10 gauge.. These things just look so massive! All my other bikes spokes measure around .080 inches and look like toothpicks compared to these on my new bike

 

[MotoMagz]

Yep they are 12gauge.. The chart at your work might have been a wire chart which is different . Either way they are nice and beefy... Sorry didn't mean to slap ya they are perfect for a motorbike !

 

[romerider153]

Post pictures of the frame

 

[Amarion1]

Not much done yet besides getting parts together and figuring out where I want the engine to sit but here she is! Took it to work to do some grinding on the motor mount since my bench grinder isn't mounted

 

[romerider153]

That thing fits in there really nice.

 

[Amarion1]

Yeah its just about right on. There's a ton of room to mount it completely vertical but I like the looks of it slanted like that

 

[MotoMagz]

Lookin good!

 

[romerider153]

Yea the motor is designed to be slanted so the flatter you can get it the better.

 

[caoboy]

Subscribing to this thread.

Did you custom make that mount or did you buy a kit?

 

[Amarion1]

Subscribing to this thread.

Did you custom make that mount or did you buy a kit?

I bought a mounting kit but I couldn't get the mounting brackets to work with the angle so im going to weld on exhaust clamps at the proper angles so it will fit right and sinch down properly. Should have just made it all myself and saved $40. Oh well. Live and learn!

 

[Amarion1]

Slow going on my build but I've ordered some more part's! :-D. I ordered a diy exhaust kit! It's got a flange and header, straight, u, 45, and 90 pieces to work with and it was only $45ish! Last night I ordered a wide pedal crank kit and a 22mm mikuni carb kit that comes with a few things. This morning I called arc racing and ordered a flywheel, rod, type 2 cam, 26lb springs and an offset timing key. I have to look at everything but I think I just need a new fork and disc hub and front and rear breaks and tires. I don't remember saying but Im using a torque converter for now. We'll see how she does anyway. Also laced my rear wheel to my HD axle kit. Still need to figure out how to true it and make it usable.

And I picked up a side project building a 79 pred for a guy at work. Got it mounted and lined up and built a Jackshaft and started puting it together. Just waiting on a wide pedal kit for it and I need to install the breaks and primary chain and fuel tank and fit an exhaust and carb which Im using from an unused 2 stroke kit. She's looking pretty good and I'm excited to test it and get crackin on mine!

To be continued

 

[Tony01]

When you set up your CVT and gearing, start counting the ratio from the output sprocket of the CVT and set it up as if it were a single speed. If you can align the output sprocket with the hub sprocket you can probably get away without using another JS. You're probably gonna push about 8-9hp there, so I think you can safely run a tall ratio like 6:1. On 26" tires, and the CVT upshifted to 1:1, your speed at 4000rpm will be 50mph. If you decide to run CVT only I think you can send those expensive go-fast parts back to AGK and save yourself a few hundred bucks.

No point in going faster. you'll realize this when you hit your first pothole at 50mph, spine begging for mercy from those skinny bike tires and saddle springs

or.. keep the go fast parts.. and forget the CVT.. it eats power.. more so as the belt wears. I tried numerous transmissions until I found what I liked on my bike.. with only 4, maybe 4.5hp I achieved 50+ with a 2-speed auto and 7.7 top gear. prior to building a 2-speed I had chosen a single speed over the CVT.. the difference was about 15mph!!


build is looking good, best of luck and can't wait to see it done.

 

[Amarion1]

When you set up your CVT and gearing, start counting the ratio from the output sprocket of the CVT and set it up as if it were a single speed. If you can align the output sprocket with the hub sprocket you can probably get away without using another JS. You're probably gonna push about 8-9hp there, so I think you can safely run a tall ratio like 6:1. On 26" tires, and the CVT upshifted to 1:1, your speed at 4000rpm will be 50mph. If you decide to run CVT only I think you can send those expensive go-fast parts back to AGK and save yourself a few hundred bucks.

No point in going faster. you'll realize this when you hit your first pothole at 50mph, spine begging for mercy from those skinny bike tires and saddle springs

or.. keep the go fast parts.. and forget the CVT.. it eats power.. more so as the belt wears. I tried numerous transmissions until I found what I liked on my bike.. with only 4, maybe 4.5hp I achieved 50+ with a 2-speed auto and 7.7 top gear. prior to building a 2-speed I had chosen a single speed over the CVT.. the difference was about 15mph!!

build is looking good, best of luck and can't wait to see it done.

Thanks for the info! I bought the cvt and an adapter for the bike I'm building for a guy I work with but the keyway is built in so I couldn't use it there and didn't want to deal with returning it to ebay for my $75 so I thought I would just try it out on my build. Eventually I want to put on a centrifugal clutch that I see is popular on these builds (can't recall the name of it at the moment) the hop up parts are really just a safety issue as I didn't want anything to blow up between my legs

I have most everything to do this project. I just need to finish this other bike first so I can get back on mine. I'm getting pretty excited to get going on it though :-D pretty soon!

 

[ElGallo]

I subscrided, wanna see what you CME up with.