212 build

GoldenMotor.com

5-7HEAVEN

Well-Known Member
Aug 2, 2008
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So you have a 10t near the pulley, 14t chained to it on the left-side jackshaft?

Then 10t on the inside jackshaft chained to the rear 48t?

So that's 14t/10t(1.4) x 48t/10t(4.8) = 6.72:1

I'm glad it works for you.xct2
 

old motorbike

New Member
Sep 21, 2008
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That is awfully tall gearing.....how does it take off from dead stop?

dnut
Accelerates very well from a dead start. The engine has lots of low end torque. Also the torque converter has lots of multiplication right off idle.
With the 10:48 it took off about the same, but midrange was stronger. It's very smooth and manageable and maybe goes 35 at whatever the gov. rpm is.
It's just a huge wide engine to get used to. I want to GPS it to see what it's doing.
 

scotto-

Custom 4-Stroke Bike Builder
Jun 3, 2010
6,505
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Ridin' inSane Diego, CA.
Accelerates very well from a dead start. The engine has lots of low end torque. Also the torque converter has lots of multiplication right off idle.
With the 10:48 it took off about the same, but midrange was stronger. It's very smooth and manageable and maybe goes 35 at whatever the gov. rpm is.
It's just a huge wide engine to get used to. I want to GPS it to see what it's doing.
I've been running mine with 10.18:1 gearing and front pulley engagement of 3,300rpm......from a dead stop the front wheel loves to leave the ground

.wee.
 

old motorbike

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Sep 21, 2008
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I've been running mine with 10.18:1 gearing and front pulley engagement of 3,300rpm......from a dead stop the front wheel loves to leave the ground

.wee.
That must be a rush!
My back wheel would probably break and I don't think mine has that much power.

If I want to go fast or wheelie I use my Busa.
 

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professor

New Member
Oct 14, 2009
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Buffalo ny area
OM, you asked in a post how the vib with that engine is but go no reply. How is the vibe now that you are running?
Mine was horrific so I mounted it on isolators below and above. I suppose, the bigger the single cylinder- the more the vibes.
 

motor_bike_fanatic

New Member
Jul 26, 2011
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Pennsylvania
yank, thanks for the link, but i was asking for a link to where they bought it from. if thats the whole transmission, thats a lot cheaper than the transmission I was looking at. the op said he got it for 129. That would bring my build way under 300 bucks. So again I ask. oldmotorbike, could you please link to where you bought your transmission?
 

beltbuckle

New Member
Aug 22, 2011
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Meridian, ID
yank, thanks for the link, but i was asking for a link to where they bought it from. if thats the whole transmission, thats a lot cheaper than the transmission I was looking at. the op said he got it for 129. That would bring my build way under 300 bucks. So again I ask. oldmotorbike, could you please link to where you bought your transmission?
just search ebay for go-kart torque converters. you will find the $129 ones in either 3/4" or 1" shaft size, and 6" or 7" driven pullies. 7" has a torqier ratio but the larger driven does not fit in the plastic cover.
 

scotto-

Custom 4-Stroke Bike Builder
Jun 3, 2010
6,505
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Ridin' inSane Diego, CA.
the 99cc has a 5/8 shaft.
You would have to sleeve the 5/8" shaft and I'm not so sure that would be a good idea as the driver mounts on less than 1/2" on the end of the driveshaft.

You're better off going with the EZM or a jackshaft with your motor.
Or if you really want to save money, you might consider a friction drive.

dnut
 
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calvynandhobbs

New Member
Aug 28, 2008
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Ledyard, CT
If you just search for comet or TAV torque converter you'll see several come up. I got mine from BMI Karts. The smallest shaft is 3/4" so for a 99CC Predator you'll need an adaptor bushing
 

calvynandhobbs

New Member
Aug 28, 2008
103
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Ledyard, CT
I really haven't looked at them since I have a 212 Predator in the garage with a $129 Torque Converter, but one I found is this link.

http://www.gsistore.com/5idx3odshadb1.html

I just saw the new HF flyer the other day and am thinking about returning the 212 since I haven't even opened it yet since they now have the 99CC on sale for $99. I'm thinking it will keep me out of trouble.
 

motor_bike_fanatic

New Member
Jul 26, 2011
377
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Pennsylvania
yeah, I wasnt considering installing a predator when the 212 was on sale. been thinking about it for a little while, but only recently decided to do it for sure. a torque converter tranny is a lot cheaper than the tranny i was gonna go with originally, so that gives me all the more reason to do it. besides, i doubt a 212 would even fit in my frame. its a cranbrook, and from seeing pictures of another members build, it barely has room for the 99cc. I am gonna take the 99cc sticker off and then cover the engine markings with jb weld or some other type of putty, maybe exhaust putty, then paint over with bbq paint to seal it. if a cop asks whats with the paint, I just have to say i started to paint the engine then changed my mind. that simple.
 

scotto-

Custom 4-Stroke Bike Builder
Jun 3, 2010
6,505
25
38
Ridin' inSane Diego, CA.
yeah, I wasnt considering installing a predator when the 212 was on sale. been thinking about it for a little while, but only recently decided to do it for sure. a torque converter tranny is a lot cheaper than the tranny i was gonna go with originally, so that gives me all the more reason to do it. besides, i doubt a 212 would even fit in my frame. its a cranbrook, and from seeing pictures of another members build, it barely has room for the 99cc. I am gonna take the 99cc sticker off and then cover the engine markings with jb weld or some other type of putty, maybe exhaust putty, then paint over with bbq paint to seal it. if a cop asks whats with the paint, I just have to say i started to paint the engine then changed my mind. that simple.
One other thing to think about is the power a torque converter will rob from a 3hp, 99cc engine. You'ld be suprised. ;)

dnut
 
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