Doodlebug db30 build advice needed

#1
Hi everybody, I'm new here and have a few questions.
I just got a stock db30 used on c.l. for 100 bucks.
Im looking to tear it apart and put a 212cc predator on it.
I already bought the engine and the mounting plate.
Should I put a clutch on it? If so how many teeth?
Should I put a torque converter instead ? If so what kind ?
What about an exhaust pipe?
Basically I dont know squat about minibikes, I'm pretty handy so the build and modifications I can figure out. I guess I'm just looking for advice for an economical build that will go fast... like 30- 40 mph or faster. Im 5'08 @ 190lb.
Any advice on what to purchase and where to get it would be appreciated. Thank you for your time.
 

Venom38

Active Member
#2
Hello Eric,
I bought a 212 for a temporary motor and only advice I can give you is buy a exhaust that isn’t near your leg. Burn my leg and wrapped that pipe multiple times. Good luck on the build these motor move quick.
 
#3
Do you want to use it off road and climb hills? If so a torque converter is a must. If it is going to be on pavement, high speeds and mostly flat terrain then a centrifugal clutch will work.
 
#4
Do you want to use it off road and climb hills? If so a torque converter is a must. If it is going to be on pavement, high speeds and mostly flat terrain then a centrifugal clutch will work.
Will one of them make the bike faster than the other ?
Is the torque converter generally a better investment overall?
 
#6
Hello Eric,
I bought a 212 for a temporary motor and only advice I can give you is buy a exhaust that isn’t near your leg. Burn my leg and wrapped that pipe multiple times. Good luck on the build these motor move quick.
Did you just buy some exhaust off amazon or ebay or something, is there a specific one I will need ? Thank you
 

Triley41395

Well-Known Member
#8
Did you just buy some exhaust off amazon or ebay or something, is there a specific one I will need ? Thank you
We just use the stock predator exhaust, only problem it melts the back fender a little. If you put on a header pipe with no muffler and you live in town, expect to get hassled by the police. The stock exhaust is much quieter. A 12 tooth max torque will work just fine, I would avoid the cheap Amazon clutch. 1-.jpg
 

Venom38

Active Member
#9
We just use the stock predator exhaust, only problem it melts the back fender a little. If you put on a header pipe with no muffler and you live in town, expect to get hassled by the police. The stock exhaust is much quieter. A 12 tooth max torque will work just fine, I would avoid the cheap Amazon clutch. View attachment 292540
Yes header pipe alone is loud, I put a muffler on for the neighbors.
 
#10
We just use the stock predator exhaust, only problem it melts the back fender a little. If you put on a header pipe with no muffler and you live in town, expect to get hassled by the police. The stock exhaust is much quieter. A 12 tooth max torque will work just fine, I would avoid the cheap Amazon clutch. View attachment 292540
How fast can you go with the 12 tooth clutch?
 

Triley41395

Well-Known Member
#13
Thats perfect...
Did you use the 35 chain or make any other modifications ?
Thank you
Yes, we use the stock 35 chain and sprocket. You have to bend the frame where the rear fender mounts about an inch to get a predator to fit. Not sure if you will have to bend if you use the mount plate but I'm also not sure that you will have room for that plate. We drilled new holes in the original mount plate. If you can not use the plate make sure you have the engine exactly where you want it before you drill your holes. If your predator has a center fill gas tank make sure you have room to get the cap on and off with the new engine plate because it is very close to the top frame on ours,you almost can not get it on and off..
 
#15
Ok Guys,
So I guess my build is going to end up being...
-Db30 original frame, seat, stock rims tires ,rear caliper and rear sprocket. ( all cleaned up and painted like new or repaired).
- h.f. predator 212 using the stock predator exhaust/muffler.
- aftermarket adjustable engine mounting plate.
- 12 tooth max torque 3/4 bore for #35 chain.
- new #35 chain
- new chain tensioner.
My dream is to make it look like the attached photo...
You see, when I was a kid I wasnt allowed to have one of these, my parents wouldnt let me. When I was 10 years old a neighborhood kid who was older gave me a rupp minibike that had no motor, I was going to fix it up but my father decided that I was going to get killed on it so he got rid of it ( in his defense i was a reckless child). So now , here I am, 50 years old ,building and buying all the toys I never could have or afford as a poor kid from the inner city...because now I can....
Thank you for the advice ,
I will post the progress... 20220803_111014.jpg 20220803_111014.jpg 20220803_111014.jpg 20220803_111014.jpg Screenshot_20220803-073519_craigslist.jpg
 

Triley41395

Well-Known Member
#16
Ok Guys,
So I guess my build is going to end up being...
-Db30 original frame, seat, stock rims tires ,rear caliper and rear sprocket. ( all cleaned up and painted like new or repaired).
- h.f. predator 212 using the stock predator exhaust/muffler.
- aftermarket adjustable engine mounting plate.
- 12 tooth max torque 3/4 bore for #35 chain.
- new #35 chain
- new chain tensioner.
My dream is to make it look like the attached photo...
You see, when I was a kid I wasnt allowed to have one of these, my parents wouldnt let me. When I was 10 years old a neighborhood kid who was older gave me a rupp minibike that had no motor, I was going to fix it up but my father decided that I was going to get killed on it so he got rid of it ( in his defense i was a reckless child). So now , here I am, 50 years old ,building and buying all the toys I never could have or afford as a poor kid from the inner city...because now I can....
Thank you for the advice ,
I will post the progress... View attachment 292560 View attachment 292560 View attachment 292560 View attachment 292560 View attachment 292561
Ok Guys,
So I guess my build is going to end up being...
-Db30 original frame, seat, stock rims tires ,rear caliper and rear sprocket. ( all cleaned up and painted like new or repaired).
- h.f. predator 212 using the stock predator exhaust/muffler.
- aftermarket adjustable engine mounting plate.
- 12 tooth max torque 3/4 bore for #35 chain.
- new #35 chain
- new chain tensioner.
My dream is to make it look like the attached photo...
You see, when I was a kid I wasnt allowed to have one of these, my parents wouldnt let me. When I was 10 years old a neighborhood kid who was older gave me a rupp minibike that had no motor, I was going to fix it up but my father decided that I was going to get killed on it so he got rid of it ( in his defense i was a reckless child). So now , here I am, 50 years old ,building and buying all the toys I never could have or afford as a poor kid from the inner city...because now I can....
Thank you for the advice ,
I will post the progress... View attachment 292560 View attachment 292560 View attachment 292560 View attachment 292560 View attachment 292561
Your photos are of a different style doodlebug than I posted. Do you have the style that's in your pictures?
 
#20
You don't have to do some of the things I said then, I thought it was a DB30 like the ones I pictured. I'll be putting a predator on one like your pictures this weekend. View attachment 292562
What kind of build are you going to do the one in the photo ? Im just interested in knowing because it seems like you have quite a bit of knowledge on these, And I want mine to come out pretty awesome.
Do you prefer the cent. Clutch or the converter ?
 
Top