Out of the Power Band: Surviving the Bog Zone

How to navigate the critical low-rev moments without losing speed

A lot of the performance in karting that makes the difference is about being quick when the engine is junk. That means low speed, low rpm parts of the track. That’s what I’ll get into today, so you can think about how to pilot your kart when the engine is weak and vulnerable.

Just thinking about your engine being so damned pathetic at low revs might be enough to revolutionise your driving, but let’s get into the nuts and bolts of it anyway.

I’m going to be throwing around phrases about low rpm driving, so just in case it is new to you here’s a bit of a glossary:

• Out of the power band: When engine rpm is below where it has any power or torque - it produces a pathetic response to throttle inputs.

• Bog: It gets so bad you lose revs when you expect to accelerate and you feel like you are driving through treacle.

• Dropping out of the rev range: When you allow the rpm to drop below the point where the engine can respond well, it goes from ok, to utter crap.

• The danger/dread zone: The time on the track where your speed has to be so low you can’t help but risk all of the above.

These all relate to the same thing - the point on the track where you are your lowest speed and therefore lowest engine RPM.

The Dread Zone

Just imagine your engine’s power curve. At low rpm if you look at the graph, your engine is crap, absolute crap. On the graph I found it only goes down to 8,000 RPM, but you will go well below that. There your engine is operating at maybe 8hp if you are lucky - useless!

But to be quick you have to flirt with dropping into that rev range, so that you can be geared well for the straight.

The low rpm is the dread zone. When your engine drops into that rev range of crapness, we say dropping out of the power band. And if you mess up there it ‘bogs down’ aka you are in trouble!

The Consequences of Mistakes in Low RPM

Dropping out of the rev range gives a wildly exaggerated punishment for a mistake.

Like, losing the rear just at the wrong moment, the axle sits down (we say that, but I just mean the inside rear wheel re-joins the track surface). Brrrr, the engine dies…. You don’t accelerate forever, you can lose so much time.

By the way, when I write brrr, I’m trying to portray a dying engine - listen to the audio version of this article and I make silly engine noises and ramble on quite a bit more.

When your motor is at its lowest rpm, you are extremely vulnerable. It's like a kryptonite moment where you can be killed. So when you are that vulnerable, driving becomes about being super caring for your kart and engine, so that you do absolutely nothing that can hurt it when it is so weak.

What Not to Do in the RPM Danger Zone

Sliding

If you slide when in the bog zone you have to correct it. You introduce a ton of drag into the kart and the engine will not pull through it. In fact, you will even decelerate when everyone else is accelerating.

Total disaster!!

If you’re slightly sideways with a solid axle trying to drive the kart straight, whilst it’s aiming the wrong way, you have to go against the kart’s desire and steer it with opposite lock… all when it has no power, poor thing doesn’t stand a chance.

So, at the lowest rpm points, be super accurate and super smart with your speed and power to keep the kart very happy.

Steering Too Much

If you are running wide because you made a mistake, or because you pushed a bit hard and the kart understeers instead, then you have to add steering angle when the kart is out of the power band.

At that point you may as well throw out an anchor. The engine will die a death. It will bog down and sit at low rpm and all you can do is wait and watch everyone fly past.

This is why extreme care to apply as little steering input as you can possibly get away with, is more important in karting than any other driving.

Even tiny bit of extra steering when the engine is weak kills you.

Tapping Another Kart

The tiniest amount of contact when you are out of revs can have a massively disproportionate effect. That added resistance to the motor can kill you. Even the dirtiest drivers know not to go near any other karts at the vulnerable rev range.

Listening for RPM Clues in the Danger Zone