Predator 212 help

[239gm]

So i have had this mini bike for 3 months from one of my buddies who took great care of it.
Last week i threw on a new spark plug(autolite) and air kit from GPS.... now when i get wide open throtle it bogs down and cuts off i put a new carb on it and not it wont turn over and run unless i have choke on and when i take it off my engine turns off... help

 

[JTSpeedDemon]

This isn't the first time we've heard about this problem. *scratches head*
Have you changed/drilled the jet after the filter/header were installed?

 

[239gm]

Yeah, The kit came with an “upgraded “jet and wheb i put the new carb on i tried the stock jet and the upgraded jet from the kit and it showed no difference in starting up

 

[950speed]

Either the new jet is too rich, so you would need to decrease in jet sizes.

OR

it’s the plug, the auto light plug is a “racing” plug meaning it has a cooler spark. High power engines have higher compressing which needs less heated spark to ignite.
So throw the jet that came with the kit in the carb and your ORIGINAL, plug see how it works, if it still Boggs down you know it’s the jet, if it runs nice and smooth then you know it’s the plug

 

[239gm]

Thanks, im going to try when i get off work and see if the spark plug is the problem, the old one i had before the Autolite was fine but i just got it for improvement lol.

I tried 3 jets:
Original from my 1st carb
The “upgraded” jet that came w/ GPS air kit
The one on The new carb i bought


Hopefully its just the spark plug but its weird cause i had it running on the Autolite plug for a few days before the problem came up when i installed the air kit

Anyways thanks

 

[950speed]

Even still, you must take into account that the weather can affect air mixture!!

 

[239gm]

True i live in Sw FL so the weather isn’t rlly that moody but thats a good point taken to take in consideration

Anyways I appreciate the help because ive tried everything and have put hours into goofy Youtube vids, cleaning both of the carbs (new and the one i had on it[witch was A1 condition and had the Made in Japan stamp on the side]) i tried every combo of switching the floats and the black rubber rings and the 3 jets i have, i cleaned the jets under the throtle bolt (they were clean already)

i switched from spark plug i had before to the one I bought a week ago. I dont havethe oil sensor pluged in and i have a full sythentic in it i changed 2 weeks ago and i poured some more in this morning.

The only thing i could think about is I haven’t used gas stabilizor in the 3 months i have had it but I always have fresh gas when it gets under the filter in the gas cap...

Could it be compression?

When i first put the Air filter kit on a week ago i needed to get the little breather filters for the two lines that previous led to the stock carb box... the guy at Auto Zone said i need ti connect the breather from the cap that says “OHM” (back of motor where the 2 spring valves are) into a Fuel filter leading into the breather line on the gas cap.... well i rode my bike for about 5 minutes and then stopped to check the gas and when I opened the cap i heard PSHHH and felt a bunch of air pressure come out against my hand.... so could a bunch of pressure bulid up on my spring valves and slightly mess the spacing up????

But after that happened i went out and bought a small “Breather Filter” that i hose clammed to the line coming from the “OHM” cover and then just cut the gas tanks line to about 1 inch........ she ran fine for a few more days of me riding about 5 min each time but just yesterday i hit full throttle and as i was slowing down it bogged out and shut off going about 30mph and since then it has not been able to run/ idle without choke and me holding thotle down about 1/4 of the way

Any other things i should try before i rip off the spring valve cover and find out if its my compression??? (Because i don’t really wanna pull my motor ,but the files and find out haha)

 

[950speed]

Yes you fixed the breather tube issue. The autozone guy was wrong. For compression you don’t have to take off the engine, only the clutch or tc to get to the shaft, then spin it over backwards to bypass compression release. To read the compression either you know how it should “feel” or you get a compression tester which goes in the spark plug hole. That’s your best bet.

If it is the valves a very simple fix is to take off the valve cover and adjust the lash, no need to take off engine for any of this.


And for the weather, it shouldn’t matter much seeing your location, but that spark plug is for high compression, again


Use the stock plug, I’m fairly certain it is the issue is your using a plug that’s too cool for the engine. Yes it may increase compression a tad, but nothing that will affect anything. The autolite plug is literally useless for your application



Did you somehow manage to shear the key? Throwing off timing

 

[239gm]

I took your advice from the prev reply about using the stock plug and i when i played around with the motor today i swapped them and tried cranking the bike... it ran a little in the sense that it idled longer before it bogged down

Once i take it off choke itll run when i have the trotle down about 3/4 of the way but then dies in ~4 seconds

Im going to try the clutch thing you explained before I see if i have to adjust the lash because to take off the OHV cover i have to take off the motor because the frame is too close

Thanks so much because w all the loooking i did nobody talked about taking off the clutch to adj the compression and it makes sense because i also recently put on a new chain like 5 days ago (i been recently getting parts and learning about my bike) and I remember hearing a hydrolic like sound coming from the motor but didnt think anything of it and then keep tighting it till my ratched got really tight

Side Note : should i be tightening the clutch that much or should i tighten it untill it catches/ starts a spin

Thanks for the help, im trying to learn about my engine/engines in general on my own and i dont have much time for reserch and practice between school and work... the help means alot and hopefully this time the suggestion about the compression solves my issue... ill keep updated when i get time to work on it and let me know if theres anyother troubleshooting to do

 

[mckutzy]

Lets see some pics of your setup...

 

[950speed]

The “clutch thing” was just to get direct access to the crank. And is just to test compression.

Now the valve lash is separate from testing the compression. Valve lash sets how far open and closed the valves go. And how “tight” the valve train is.
And yes still test the engine without the clutch, could be as simple as the clutch is shot and binding, straining the engine.