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Old 09-12-2019, 03:19 PM
Mnshaw Mnshaw is offline
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Default Help & advice needed!!

Just got up Baja Doodle Bug it has a 2.5 lifan motor. I want to put a predator 212 in it can anyone offer advice or tips and what I will need to do it? Just got this mini bike never been really wrenched on stuff got this as a project for me and my kid he's five
Old 09-12-2019, 03:48 PM
madprofessor madprofessor is offline
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Your 5-year old kid would be at serious risk if you put 6.5 hp. between those little legs. It's way too much power and speed for that to be safe. Even the stock box motors are a lot to handle. Reducing startup torque by dropping a 50-tooth sprocket on the rear and a 12-tooth on the shaft won't be safe, because the top speed will increase proportionately. I know Harbor Freight sells those for $130 all day, but if your kid's going to ride it, just don't. Stick with what you've got to teach the kid, and buy another roller frame and a 212 just for yourself.
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Old 09-12-2019, 05:46 PM
Mnshaw Mnshaw is offline
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Hes got his own bike im building this for me. I want something to pre around on and have some fun. Have u ever built one of these?
Old 09-12-2019, 05:49 PM
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Hellion Hellion is offline
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Post some pics of the condition it is in now.

Should basically be a drop-in modification.
"I'm just here for the gasoline"
Old 10-07-2019, 12:09 PM
mediumsizedhog mediumsizedhog is offline
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I just put a 212 on a doodlebug. It was super easy. Buy an engine mount adapter plate to make that easy, otherwise you will have to drill some new holes in the frame. I put a torque converter on mine which required me to mod the torque converter and cut off the chain tensioner, but a max torque clutch would work just fine for this. I used the same chain, same sprocket at first but got a smaller one later. Fuel cap on the 212 ends up lining up right between the top frame bars and comes out no problem. It was overall super simple.

Pick up one of these and you'll have the predator mounted in minutes.


Really you'll just need that plate, a clutch for a 3/4" shaft, and probably a chain breaker and a new master link so you can resize the chain. I changed the rear sprocket on mine but you don't have to. Removed governor as well. My doodlebug does 50+ mph. It's pretty scary actually.
Old 10-07-2019, 02:19 PM
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Flyinhillbilly Flyinhillbilly is offline
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I had a doodlebug with a racing clone on it that burned a mix of nitromethane and methanol.
It was dangerous, but it was also a lot of fun to whip all the locals on their 4 wheelers and side by sides on a mini bike. I drilled new holes in the mounting plate and didn’t change anything else. It’s a super easy conversion.
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Last edited by Flyinhillbilly; 10-07-2019 at 02:20 PM. Reason: I kant spells
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