Motovox mbx10 with 212cc predator engine, way too much low end torque.

[Kybiker]

Hello everyone,
I have a motovox mbx10 that I installed a 212cc predator engine and now the bike has way too much low end torque.

The motor has a lot of mods.

After some research I believe that I need a smaller sprocket?
60 tooth do what I need?

Does anyone know the specs so I can buy one that will bolt up with out any modifications?

Picture incoming.

 

[cheezy1]

You will have to but the DB/Motovox sprocket adapter...like 30 bucks or something now. Then find the size sprocket ring to bolt on the adapter. It is all bolt on parts and no hard core modifying.

 

[cheezy1]

The adapter is in this pic..

 

[OND]

Yep cheezy is telling you right ! Then you can change your rear gear to what ever you want. [MENTION=55384]Daniel Coop[/MENTION] just did this to one of his Motovox bikes.

 

[Kybiker]

Is this it?

Is this it?
https://www.OldMiniBikes.com/doodlebug-sprocket-adapter-2-ombd3.html?category_id=1441

 

[OND]

Yep...that's It ! You can also get your two piece sprocket there to.

https://www.OldMiniBikes.com/-35-split-sprocket-60t.html

 

[cheezy1]

Yep...same one. They do sell the karting one piece sprockets also...but it is easier to use the two piece one in case you wanna change around the gearing and leave the wheel on the bike. lol

 

[Kybiker]

Thanks.
Next question what size sprocket 60 tooth or smaller?
This bike is for my 13 year old son and right now he is scared of it.
Before you know it you will be on your back with the bike on top of you.

I would like a sprocket that will keep the front wheel on the ground.

 

[OND]

The 60 th sprocket should work just fine...it will kill some of the power when taking off...but will give him more top speed . In that case you can adjust the throttle stop on the engine.

 

[cheezy1]

I have a 58t on my daughters..it still comes up but not too bad.

 

[Kybiker]

I have a 58t on my daughters..it still comes up but not too bad.

Thanks for the post.
I think I will try out a couple since they are so cheap.
Not sure since I have no idea what I am doing but I think I will try out a 55 tooth and 58 tooth.

 

[cheezy1]

Thanks for the post.
I think I will try out a couple since they are so cheap.
Not sure since I have no idea what I am doing but I think I will try out a 55 tooth and 58 tooth.

Your welcome

 

[Kybiker]

Blowing my mind here.
I live in Kentucky with lots of hills.
I am thinking about going with a 53 tooth.
Anybody try a 53 tooth?

 

[Kybiker]

I just order the sprocket adapter Ana a 53 & 58 tooth sprocket.
After testing I will update.
Thanks everyone for the help.

 

[fistfullabar]

Why not keep the smaller stock engine till he gets the hang of it?

 

[Kybiker]

Why not keep the smaller stock engine till he gets the hang of it?

We have had the mini bike for several years.
He rode it until the keyway on the crankshaft "chiped".
The original engine is toasted.
That is why I picked up a new motor.
I got the new sprockets in so I will update in a couple days.

 

[fistfullabar]

Same thing happend to my 2.8 chipped a piece right off the crankshaft!!!! Had the clutch just spinning! Have fun with ya son. Its the best way to minibike. With the fam!

 

[Kybiker]

Update,
I got the sprocket adapter and 58 tooth sprocket installed and it really smoothed the bike out. It is no longer jerky and wanting to pop wheelies.
It is way better now.

I also I sandwiched 1/2 rubber between the motor mounting plate and frame & that took away a lot of the vibration.

It is a dream to ride now.
Thanks everyone for the advice.

 

[2strokd]

Blowing my mind here.
I live in Kentucky with lots of hills.
I am thinking about going with a 53 tooth.
Anybody try a 53 tooth?

I live here in the BlueGrass as well. You close to Breathitt County?
He wasn't going about those hills....And curves. You would think the highway department was allergic to straight flat roads. Hard to find a 1/4 mile straight stretch for test hits....