Governor and throttle adjustment

#1
Hey Guys, I was given a Doodle Bug DB30 Baja 97cc engine mini-bike the other day. I have cleaned it up (somewhat) as it had dirt dauber nests all over and in it. I cleaned the carburetor but couldn't get it to run. So, I ordered a new carb along with the throttle and cable off Amazon. Carburetor was no good, so got the replacement today. I got the bike running, but can't figure out how to adjust the throttle and governor. Can anyone show me some photos of how the governor is supposed to be adjusted? If I decide to keep this thing to ride around the neighborhood, I will need some new tires. The kids that had this thing had parents with money and didn't take care of it. I need to change the oil as it's black as the ace of spades. What weight oil should I put in it? I have a new rewind ordered for it as the spring broke inside it and the crank rope broke on me when I tried to crank it. I have cut the coil spring off and heated it so I could make a bend in it and replaced the rope. I don't know how long this spring will hold up, thus the new one is ordered. I had to clean the rust off the flywheel and coil and set the air gap at .012. Is that a good gap for this engine? It seemed to run pretty decent one I tried smoothing out the carburetor, but the governor was not connected and I'm not sure I got it right. Obviously, I don't have it right or I wouldn't be asking, right? Anyway, any advice on how to properly set and adjust the governor would be GREATLY appreciated. I had one guy on another forum tell me to just remove it, but I don't like that idea and don't see how it would even run without it.
 

Harquebus

Well-Known Member
#2
You should post some pics so we can see how abused this machine is, and whatever's missing or disconnected.

I'd recommend 10W-30 motor oil but straight 30 weight [the old standby lawnmower oil] has been used for decades. Multi-viscosity oils are basically intended for water cooled automobiles. Air cooled engines run much hotter.

The coil gap at the magneto is typically the width of a business card, but if it runs, it runs.
 
#3
Thanks, Harquebus. I was planning on running straight 30 weight in it. I live in Central Florida and it's pretty much hot here year round. We DO get a few days of 45 degrees or so in the mornings, but they are way too infrequent for me and no need to use a multi-viscosity oil for those 5 days of the year! LOL I miss the cold weather and am seriously considering moving back to the real south. Probably back to TN or AL. But I still need help with the governor.
 
#4
Thanks, Harquebus. I was planning on running straight 30 weight in it. I live in Central Florida and it's pretty much hot here year round. We DO get a few days of 45 degrees or so in the mornings, but they are way too infrequent for me and no need to use a multi-viscosity oil for those 5 days of the year! LOL I miss the cold weather and am seriously considering moving back to the real south. Probably back to TN or AL. But I still need help with the governor.
No YouTube out there for this popular engine? Is it a Lifan engine?
 
#5
To be honest, I have no idea what the heck it is. It LOOKS like a Briggs & Stratton. No identifying names anywhere except on the crank rope cover and it just says baja 97cc. I got it runnning this afternoon after cleaning and lubing the clutch. I need to find a new, long governor spring because of the rust on this one. I gotta get a new gas cap too.
 
#6
I'd recommend 10W-30 motor oil but straight 30 weight [the old standby lawnmower oil] has been used for decades. Multi-viscosity oils are basically intended for water cooled automobiles. Air cooled engines run much hotter.
Not to start a big war, but I have to disagree with this statement. 10-30 oil and straight 30w oil are the same viscosity when hot. The only time there is a real difference is when the engine is cold. 10/30 weight flows better cold, flows the same when warm as straight 30w, this means better lubrication on start up. There is a reason why straight weight does not meet spec for any new engines. The only reason that straight weight oil was used in the past was because they had not figured out how to make multi-weight yet.
 

Harquebus

Well-Known Member
#7
Not to start a big war, but I have to disagree with this statement. 10-30 oil and straight 30w oil are the same viscosity when hot. The only time there is a real difference is when the engine is cold. 10/30 weight flows better cold, flows the same when warm as straight 30w, this means better lubrication on start up. There is a reason why straight weight does not meet spec for any new engines. The only reason that straight weight oil was used in the past was because they had not figured out how to make multi-weight yet.
I know that but unless you're riding in temps below freezing, 30 weight is the recommendation--the usual reason being that multi-grades burn off faster than the straight grades and tend to varnish the cylinder walls leading to a loss of compression [and therefore power]. The multi-grades tend to cause higher than normal oil consumption too, until they reach 212° where it probably tapers off a bit.

Matters little to our basic putt-putt engines, and we're not racers or in competition so the point is probably rather moot.
 
#8
I wouldn't spend much time/money on that engine, most people toss the 97cc engine and install a 212 Predator ($100 + $25-50 for a new clutch or torque converter) or other larger engine.

BA off-road tires
https://www.amazon.com/Replacement-Tubeless-Tires-A051-POWER/dp/B07F21NCLG/ref=sr_1_4?keywords=145/70-6+tires&qid=1567804209&s=gateway&sr=8-4&tag=omb2020-20

Street tires
https://www.gopowersports.com/15-x-5-6-ultimate-mini-bike-street-tire/

DBs go for $400-600 in my area (they usually have already had a 212 swap) so don't give it away (except to friend/family) if you don't keep it. I like the early style DBs but not willing to pay what people want for them, I bought 2 new Coleman CT100Us for less than local used DB prices.
 
#13
Thanks for the information, Charles. I just got home from Walmart a little while ago and changed the oil on it with 10W-30. Man, the old oil had probably NEVER been changed. That oil was as black as Elvis' hair was when he was a movie star! LOL I took some photos of it but will have to get my daughter to post them for me. I'm not computer savvy and she has to do that stuff for me. As for tires and another engine, I'll have to hit the lottery for a few numbers to do any of that. I'm disabled and live on a fixed income. Not a lot of wiggle room. I do like the idea of a Predator 212 and some street tires, though. I guess I'll have to save up!
 
#15
I have the same 97cc baja engine on a motovox mbx 10. gettin the gov/throttle to work right is a real SOB for some reason. never had so much trouble. if it weren't for the fact i'd like my wife to start out on this lower hp, i'd just toss the 212 and cvt on it. I looked all over the place and really couldn't find a thing on them online to set it up, spo its trial and error at this point. . to make matters worse, the springs had been monkied with on mine and the gov arm "tweaked". I guess they thought they could gain mph by playin with this stuff. I'm just tryin to put it back to stock so she can run it a while and then up the hp with the 212. I have it to where it will idle now and the air mixture screw should be about spot on. Just seems kind of doggy down low but i'm 220 lbs and this is just a 3 hp or so engine. I'll update you if i figger things out. Oh make sure to run a fuel filter and check the tank, they are notorious to rust badly on the inside. in fact, a lot of things seem to rust on this engine premature;y IMO.
 
#17
I'm in SE Virginia, summers are hot. I bought a new Craftsman lawn tractor in 2006, it has a 724cc, 24 HP, B&S v-twin (air-cooled). I broke it in on 10W-30 dino then switched to 20W-50 Mobil 1 V-Twin, it still doesn't burn, or otherwise use, any oil. I'm pretty lax on oil changes since it's pressurized lubrication with a spin-on filter and using 20W-50 full synthetic, but I check the oil level before every use, even though it has a long history of not using/losing oil. So much for the muti-viscosity oil burning off theory.
 
#19
I should have taken before and after photos. It was filthy and had mud dauber nests everywhere. The engine was almost solid black! Anyone know if Lowes might have some springs that would work on the governor? The long spring is very rusty and I don't really trust it to last too long.
 
#20
I should have taken before and after photos. It was filthy and had mud dauber nests everywhere. The engine was almost solid black! Anyone know if Lowes might have some springs that would work on the governor? The long spring is very rusty and I don't really trust it to last too long.
The engine numbers should be lazer etched on the front side of the engine block, near where the low oil sensor would be if it had one. Sometimes faint, but there.
I would get the correct governor/ throttle linkage for that engine. Small engine governors like it.
 
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