Reasonable engine upgrade alternatives

[Scottusa]

I purchased a trashed out MB165 with a seized 196cc motor that had been run without oil.

I see OEM choices from the Bajamotorsports.com and the OldMiniBikes warehouse etc and I also
see the PREDATOR motors at HarborFreight.

But are there Briggs and Honda brand name choices that bolt right in and with throttle
hook ups and exhause etc in the right places ?

How bout slightly more powerful options ? Will any slightly bigger engines also fit right
in without too much trouble or mods needing to be made ?

 

[Newoldstock]

I purchased a trashed out MB165 with a seized 196cc motor that had been run without oil.

I see OEM choices from the Bajamotorsports.com and the OldMiniBikes warehouse etc and I also
see the PREDATOR motors at HarborFreight.

But are there Briggs and Honda brand name choices that bolt right in and with throttle
hook ups and exhause etc in the right places ?

How bout slightly more powerful options ? Will any slightly bigger engines also fit right
in without too much trouble or mods needing to be made ?

Take the engine apart and post some pictures.
Run without oil is not an automatic death sentence.
Let me see.......

 

[Scottusa]

The predator motor at Harbor Freight I see is $119 dollars and it would seem well worth it to not have
to disassemble, diagnose, buy parts and rebuild it and have anything close to the life left compared to
a new engine.
Moreover.... I have discovered that all motors larger than 212cc have larger one inch crankshafts and it is now clear
that clutches and sprockets are not available in that size with teeth that fit the 420 chain size etc. ( or any chain
size for that matter.) too bad because Harbor Freight has the Honda GX390 clone that I think would fit in
the mini bike if I remove the gas tank.

This makes if very difficult to consider any larger engine even though it might fit because then I would have
to find another jackshaft and or rear sprockets to fit the chain sizes etc. Maybe the torque converters
are easier to work with in the one inch diameter crankshaft sizes... I dont know.

There must be hundreds of guys before me that have figured out the best ways to upgrade in engine power.

I was surprised to find how rare it is to use 420 chain size in the go kart / mini-bike industry.

 

[dylanbecks]

Just get a predator and use it

 

[jdblood202]

The predator motor at Harbor Freight I see is $119 dollars and it would seem well worth it to not have
to disassemble, diagnose, buy parts and rebuild it and have anything close to the life left compared to
a new engine.
Moreover.... I have discovered that all motors larger than 212cc have larger one inch crankshafts and it is now clear
that clutches and sprockets are not available in that size with teeth that fit the 420 chain size etc. ( or any chain
size for that matter.) too bad because Harbor Freight has the Honda GX390 clone that I think would fit in
the mini bike if I remove the gas tank.

This makes if very difficult to consider any larger engine even though it might fit because then I would have
to find another jackshaft and or rear sprockets to fit the chain sizes etc. Maybe the torque converters
are easier to work with in the one inch diameter crankshaft sizes... I dont know.

There must be hundreds of guys before me that have figured out the best ways to upgrade in engine power.

I was surprised to find how rare it is to use 420 chain size in the go kart / mini-bike industry.

Yea, I've had both a predator 420cc and a Honda gx390, due to the size and weight of the motors, cost of anything that hooks up to a 1" crankshaft, and cost of aftermarket parts I opted to not use them on a mini bike. I think that's kind of why alot of people don't use them. With all the hop up parts available on the honda gx200 and its clones, why bother with the big bulky expensive motors when you can have a lighter one that fits in alot better, cheaper to build, and get more than enough power out of? Granted, that doesn't stop me from wanting to do a predator 420cc drag bike someday. That's for when I have a more disposable income though.