New member here, just bought a used doodlebug for the kids to tear up the yard with. Appears stock, 2.8 Lifan. Runs good, stops good, but obviously lacking. Just ordered a Predator 212 and am planning to build it up over the winter with the kids. I've already gained a ton of knowledge from the forums here, super cool to see so much interest in mini bikes. Hoping someone can lead me in the right direction. The old Lifan that's currently in there seems to be reliable, but there's a ton of hesitation and there's not enough power there to get the kids back up the hill in the backyard. While the engine swap might be enough for them (the oldest is 9), I also thought it would be a good learning experience for them to help with an engine build. It seems like most builds I run across focus on top end performance. I'm interested in a build that increases low end performance. I'm tired of pushing this thing back up the hill and see no reason for the little sh1ts to be doing 45 or 50mph around the neighborhood.
Suggestions for doodlebug build
- Thread starter cmc
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- Tags build doodlebug suggestions
stock 6.5 predator and stock 72 tooth gear will have those kids doing wheelies even will wheelie with a full size adult. . i would swap out the rear gear for a 60 tooth so there is less torque and just set the throttle limiter so there not going 50mph. there will still be enough power for the kids to get up hills.
Greetings...sounds like this for kids and yourself ( mostly) 
go with the 212cc and leave governed and screw the throttle stop in alot for kids(don't let them see how that's done) and when you want to ride screw it out to get speed for yourself is what I would do if you want to be safe for them....teach them other stuff like changing oil,chain adjustments and repairs,tightening loose bolts n stuff...cheers
go with the 212cc and leave governed and screw the throttle stop in alot for kids(don't let them see how that's done) and when you want to ride screw it out to get speed for yourself is what I would do if you want to be safe for them....teach them other stuff like changing oil,chain adjustments and repairs,tightening loose bolts n stuff...cheersFor the kids? No way. That 212 will be PLENTY completely stock. Honestly, if I it's for the kids I would consider upgrading the brakes before you mess with getting more hp from that 212.
Now, once YOU get hooked and wanna go fast, well then you might want to start looking into beefing up the engine.
Now, once YOU get hooked and wanna go fast, well then you might want to start looking into beefing up the engine.
First, I want to again thank everyone for the input. Just wanted to update everyone... We got the new Predator 212 in there with a stage one kit and 10 tooth sprocket up front. New engine fired up on the second pull and the initial test ride had me doubting that the engine swap did much good, it carried me up the gradual incline of the street in front of the house with barely more speed than the stock 2.8hp. It was then I realized the choke was still fully on. I've been riding various types of motorcycles since I was 12 or 13, I'm 38 now and despite living in MN and having snow 8 months of the year, I still manage to put on 10 or 12 thousand miles a year on my Harley. That's a lot for anyone living in my neck of the woods. I've also done a lot of sketchy shit in my time so I'm sure you can all imagine my shock when I turned the choke off, blipped the throttle, and without any warning whatsoever, immediately found myself flat on my back in the driveway with the kids staring at me in a combination of disbelief and horror. I honestly don't think the rear tire moved at all. The entire works (myself included) instantly pivoted about the rear axle until we hit concrete. It was like riding on the end of a hammer. Holy shit.
A 212cc powered DB will whoop most people's butt, especially with that 1st twist of the throttle. I'd like to see more unique DB builds like JDogg or Chipper's bikes, I've built some interesting ones but hardly unique. One built for a friend who missed a couple of days work after doing a driveway flip before he even hit the street with it, his wife made him beg me to take it back which I did. That's what started me down the DB path and got me back into vintage minis. This was my blue monster that did 51mph with a 60 tooth rear sprocket and about 5000rpms to carry me that fast and the other is the "Lady Bug" which belongs to my youngest Daughter. It's a 3hp briggs right now but will soon get a baby Predator, the little mill can carry a 100# girl along fine. My next DB will be a 60mph machine with a legit 15hp Predator not the goofy governor rigged blue clone that the blue bike had.
LOL, ribs were pretty tender for a couple days. Buddy of mine stopped by the house and I told him you gotta ride this thing.. Couple minutes later and he was on the ground too. Snapped a foot peg off so I got another one on the way. Added a stiffer return spring and ran the limit screw in half way and it's now ride-able again. Ordered a 60T sprocket for it and a new 7/8" throttle and cable too. That stock throttle on there is a pile. Hoping the 60T will help dump some of the torque. Things a monster.
Yep..cheap little hot rods..too me fun coz you can one together so cheap..I get barely used 2 to 5 yesr old db30s here for less than $200 ..another 200 in and even if you burn it to the ground you can get another ..speaking of..I keep a small tundra fire extinguisher in a little pack on straped on back when I ride...enjoy!!