Raději seřiď brzdu, než abys jel se špatnou brzdovou destičkou.

Raději means rather, preferably, or better in this kind of sentence.

So Raději seřiď brzdu... means something like Better adjust the brake... or You’d rather adjust the brake...

A very common spoken variant is radši, which means the same thing but is more colloquial.

Seřiď is the informal singular imperative of seřídit.

So it is a command or recommendation directed at one person, like:

• Seřiď brzdu. = Adjust the brake.

Because seřídit is a perfective verb, it suggests a single completed action: adjust it properly, get it done.

If you were speaking to more than one person, or using formal you, you would say seřiďte.

Seřídit usually means adjust, set correctly, tune, or align something mechanical.

So seřídit brzdu is not necessarily repair the whole brake. It means something more like adjust the brake so it works properly.

That is why seřídit fits well in a sentence about a brake and brake pad.

Because brzda is the direct object of the verb seřiď, it has to be in the accusative case.

• nominative: brzda
• accusative: brzdu

So:

• brzda = a brake as the subject
• seřiď brzdu = adjust the brake

This is a very common Czech pattern:

raději X, než aby Y

It means:

better / rather X than Y or X rather than (for someone) to do Y

So:

• Raději seřiď brzdu, než abys jel...
• Better adjust the brake than ride...

The než aby structure often sounds more natural in Czech than trying to copy the English rather than directly.

Because abys is the standard correct form.

It comes from aby + jsi, but in normal Czech this is contracted:

• abych
• abys
• aby
• abychom
• abyste
• aby

So aby jsi is generally considered nonstandard. Learners should use abys.

After aby, Czech normally uses the l-participle form of the verb, not the present tense.

So:

• jedeš = you ride / you are riding
• abys jel = so that you would ride / for you to ride

Even though jel looks like a past-tense form, here it is not past in meaning. After aby, it is part of a different construction that expresses something hypothetical, intended, or undesirable.

That is why:

• než abys jel = than for you to ride / than you ride

Yes.

The l-participle agrees with gender, so:

• to a man: než abys jel
• to a woman: než abys jela

The imperative seřiď stays the same for one person, but the participle changes.

For plural or formal you, you use seřiďte and abyste:

• Raději seřiďte brzdu, než abyste jeli...

If you are speaking formally to one man, you would normally say:

• Raději seřiďte brzdu, než abyste jel...

To one woman:

• Raději seřiďte brzdu, než abyste jela...

So the command takes the -te form, and after abyste, the participle still reflects the real gender/number of the person.

The basic preposition is s meaning with, but Czech often uses se instead for easier pronunciation.

That happens especially before words beginning with certain consonants or consonant clusters, including š.

So:

• se špatnou... sounds natural
• s špatnou... is harder to say

This is a pronunciation-based variation, not a change in meaning.

Because after s / se, Czech uses the instrumental case.

The noun is destička and here it becomes instrumental singular:

• nominative: brzdová destička
• instrumental: brzdovou destičkou

The adjectives have to agree with the noun, so:

• špatná → špatnou
• brzdová → brzdovou
• destička → destičkou

So se špatnou brzdovou destičkou means with a bad brake pad.

They are not the same thing.

• brzda = brake
• brzdová destička = brake pad

So the sentence is talking about adjusting the brake but also mentions riding with a bad brake pad. That is perfectly normal, because the brake pad is one part of the braking system.

Yes, Czech word order is flexible.

The original sentence is natural and neutral:

• Raději seřiď brzdu, než abys jel se špatnou brzdovou destičkou.

But you could also shift emphasis:

• Brzdu raději seřiď, než abys jel...
• Raději brzdu seřiď, než abys jel...

These variations are possible, but the original order is a very natural way to say it. The než abys jel... part tends to stay together as a unit.