212 full throttle

[EggyChief97]

Hey guys so I have a problem and I'm not sure if it's my clutch or my 212 predator, I recently bought the minibike frame without a motor, originally had a 80cc motor in it but I wanted to go all out, so I bought a 212 cc predator and brand new clutch and chain. It's finished now and I'm not sure if it's the motor or clutch giving me problems, motor runs perfect and gets me moving so I don't believe it's the clutch that's the problem or not but when I'm full throttle it goes at top speed for about 2 seconds then it either revs down a tad bit to disengage the clutch or the clutch just can't hold the speed, I'm just not sure what to try at this point, both the motor and clutch are brand new like put them both in not even 5 days ago. I'm just stumped

 

[mrdeadman1]

its the governor in the engine, if it is not fast enough remove it or gear higher

 

[rocketkart]

Sounds like the governor is kicking the throttle back once it gets up to speed. Id go Direct throttle right to the carburetor and eliminate the governor if your wanting to go faster.

 

[mckutzy]

Hello and welcome...
Post a few pics of your setup...
Whats you gearing, OD of your tire size???

 

[EggyChief97]

I'll post pictures of it tomorrow, it's the stock rear gear that came on the mini bike but a 12 tooth gear on the shaft

 

[Mrmonk7663]

It’s the govenor. Take the side cover off and remove the govenor.

 

[itsid]

sure sure.. it could be the governor..
but frankly I doubt it..

answer mckutzy's question first, then we can tell if it is or if your gearing is just way off.
After what we usually see around, I'd almost bet it's NOT the governor at all.

'sid

 

[mrdeadman1]

if the gearing is way off, it's still the governor kicking in that is being felt. Like I said remove the governor of gear higher

 

[EggyChief97]

The hearing on the minibike is a 12 tooth clutch to a 75 tooth rear sprocket, also the build pictures

 

[Mrmonk7663]

You have plenty of gear in the mini bike. I still say it’s the govenor. But case, I notice you have a header. Have you changed the jetting at all?

 

[mrdeadman1]

ok how tall is that rear tire?

---------- Post added at 12:09 PM ---------- Previous post was at 12:07 PM ----------

I think you need a 60 tooth rear on that for what you are wanting. that'll put you at a 5:1 and increase your top speed.

 

[EggyChief97]

I currently have not drilled out the jet, I am planning on doing that soon, the hight is I believe 10-12 inches for the tire hight

 

[mrdeadman1]

so yeah the 60 tooth would get you some more speed before the governor kicks in and would still be ok with the clutch. Removing the governor would be the next step after that, it pretty simple and as long as you retain the stock valve springs its safe. I wouldn't jet the carb unless you put a high flow air filter on as well.

 

[EggyChief97]

Thank you for all the info guys, I did some riding around today and have concluded that it is the governor, I will be putting on a 69 tooth sprocket for a little more speed which is what I'm after but thanks again everyone

 

[madprofessor]

EggyCheif97: Please DON'T drill out your carb main jet (jet singular, the idle jet doesn't figure in this). So many people have screwed up their engines that way, start replacing carburetors, doing weird stuff to make it run right. Spend the $10 to order high performance jets and leave your drill alone. Without a drill press and an absolute locking 90 degree vise under it, no human hand can drive a drill bit that fine perfectly straight to get a hole that's measured in thousandths from end to end. No plugging here, but I got mine from diyperformance based on their long experienced recommendation. They also advise against changing out the emulsion tube (E-tube), as you can't get everything adjusted right for the new jets then. Also, you won't even notice the 6-tooth change from a sprocket that big. Go straight to a 60-tooth.
mrdeadman1 is correct on needing a high flow air filter, just don't get the flat adapter for it, use only the billet venturi type that really draws in air, and when he says running without the governor is safe with the stock valve springs, as they will start floating and holding you back before you can spool up enough rpm's to explode the factory flywheel and send pieces of it through your leg.
Mrmonk7663 says to split the case of your motor to remove the small governor parts inside, please don't at this stage, just disconnect its springs and rods etc. on top of the engine and rig your throttle cable direct.
By the way, like everybody says, yes it's your governor, coupled with the fact that your huge rear sprocket should have great startup torque but very low top end.

 

[bob58o]

Who is this guy? ^
Drilling jets is easy and fine.
You are enlarging a hole that is already there.
If the original hole is straight, the enlarged hole will be straight too.
DON’T bypass the governor!
Remove it completely.

 

[Hellion]

Who is this guy? ^....

I thought he was you—your alternate account for spreading disinformation [and trolling].

Drilling jets is easy for people accustomed to micro work or building ship models, etc. but maybe not everyone. You need a steady hand, a good light source and patience. Very easy to break those micro drill bits like a toothpick, too...