Whats the risk of bypassing the governor?
- Thread starter Kbg
- Start date
Sit on your bike. Look down at where the flywheel is. Now, imagine where the pieces of that flywheel might fly at the speed of sound when it explodes. The engine was never designed to spin any faster than it's governed RPM.
Your question asked about damage to the engine. Yes, the engine would be destroyed beyond repair if the connecting rod breaks at high RPM.
Your question asked about damage to the engine. Yes, the engine would be destroyed beyond repair if the connecting rod breaks at high RPM.
I would say an exploding flywheel is more of a danger than a broken connecting rod but I'd rather not experience either, or both...
https://oldminibikes.com/forum/inde...ur-engine-and-oldminibikes-please-read.35509/
https://oldminibikes.com/forum/inde...ur-engine-and-oldminibikes-please-read.35509/
Now, after you have read these replies, think about this aspect, which has not been mentioned:
All of this mayhem has happened to you or another rider, on a mini bike, with only marginal brakes, traveling at a speed it was never designed to travel.
Where will you finally skid to a stop?
Have fun and be safe.
All of this mayhem has happened to you or another rider, on a mini bike, with only marginal brakes, traveling at a speed it was never designed to travel.
Where will you finally skid to a stop?
Have fun and be safe.
If you aren't up to building an engine, consider a Ducar 212. The Ducar is governed at 5300 rpm, 48% higher than a typical clone, and its PVL flywheel is rated for much higher rpm than that. It also has a stronger block than most clones. It should provide a significant performance increase over most stock minibike engines at a reasonable cost.
https://www.dynocams.com/item/212-1000/ducar212/
https://www.dynocams.com/item/212-1000/ducar212/
Yeah there's real danger of the engine simply seizing from the higher revs/heat to blowing up. There's the story of a cast iron flywheel from a Briggs 5 HP that "blew up" from rotational forces because it was compromised (cracked) prior to assembly (dropped on the floor, etc). It was a karting engine that was ungoverned and running on methanol probably and this incident caused a fatality or severe injury leading to the requirement for billet flywheels.
What bike and engine is it? There's a phenomenon on most stock engines known as valve float (or flutter, can't recall). It's with stock valve springs, which at a certain RPM just cannot open and close the valves fast enough to maintain that higher RPM; they're "floating" and thus you're not getting full combustion. It's almost like a safety check on over-revving.
I feel that an ungoverned engine or one governed to run higher than the factory-set 3600 revs is okay up to a certain point. You can adjust the governor -- it is not 3600 only and nothing else.
What bike and engine is it? There's a phenomenon on most stock engines known as valve float (or flutter, can't recall). It's with stock valve springs, which at a certain RPM just cannot open and close the valves fast enough to maintain that higher RPM; they're "floating" and thus you're not getting full combustion. It's almost like a safety check on over-revving.
I feel that an ungoverned engine or one governed to run higher than the factory-set 3600 revs is okay up to a certain point. You can adjust the governor -- it is not 3600 only and nothing else.
The original question was about "bypassing" the governor. That would mean just leaving it inside the engine and doing some cheap solution to gain more RPM, like wiring the spring solid. The answers in this topic refer to such a bad decision.
The proper REMOVAL of the governor would require removing the side cover and the cylinder head from the engine to remove the connecting rod and replace it with a billet connecting rod. Remove all governor parts while you are in there. Install a billet flywheel and stronger valve springs.
This would be a lot of money to some people, but it is the safe way to go faster.
A torque converter can be had for about a hundred dollars and would be a huge performance improvement over a clutch and chain if you ride off road.
The proper REMOVAL of the governor would require removing the side cover and the cylinder head from the engine to remove the connecting rod and replace it with a billet connecting rod. Remove all governor parts while you are in there. Install a billet flywheel and stronger valve springs.
This would be a lot of money to some people, but it is the safe way to go faster.
A torque converter can be had for about a hundred dollars and would be a huge performance improvement over a clutch and chain if you ride off road.
DITTO to post # 16. If the billet rod and flywheel are TOO much money, then keep the engine governed the way it was manufactured. Anybody who has delt
with any sort of racing or performance machinery ( as I'm sure many of us on here have ) understands the old saying " how fast do you want to go, how thick is your wallet ". It's not any different just because it's a mini bike. Between mini bikes and go karts I have 5. Along with 2 extra engines on the work bench, just incase. Every one of them has a billet rod and flywheel, along with the usual internal hop up parts. Do it right, or leave it alone.
with any sort of racing or performance machinery ( as I'm sure many of us on here have ) understands the old saying " how fast do you want to go, how thick is your wallet ". It's not any different just because it's a mini bike. Between mini bikes and go karts I have 5. Along with 2 extra engines on the work bench, just incase. Every one of them has a billet rod and flywheel, along with the usual internal hop up parts. Do it right, or leave it alone.
While we are on the subject, most of us can show you how to tweak the governor to allow some more RPM, safely and without spending any money. My governed engines have aftermarket replacement carburetors with adjustable idle circuits, so I can richen the idle for easier starting and better power. With the governor still connected, I moved one small spring on the governor arm and the engines spin at about 38-3900 RPM.