Jant teli sıkıldıktan sonra teker göbeği yeniden kontrol edildi.

Sıkıldıktan sonra is a very common Turkish time expression meaning after ... was done / after doing ....

It breaks down like this:

• sıkıl- = to be tightened
• -dıktan sonra = after

So:

• sıkıldıktan sonra = after it was tightened

A useful point: this is not a main verb by itself here. It creates a subordinate time clause:

• Jant teli sıkıldıktan sonra ... = After the spoke was tightened ...

This structure usually implies that the first action was completed before the second one happened.

Because sıkmak and sıkılmak are different forms:

• sıkmak = to tighten / squeeze something
• sıkılmak = to be tightened or to get tightened

In this sentence, the focus is not on who tightened the spoke, but on the fact that it was tightened. That is why Turkish uses sıkıl-.

So:

• Jant telini sıktı = He/she tightened the spoke
• Jant teli sıkıldı = The spoke was tightened

These are examples of a very common Turkish structure often called an indefinite noun compound.

Pattern:

• Noun + Noun-(s)I

So:

• jant teli = rim spoke / literally rim wire
• teker göbeği = wheel hub

In this pattern:

• the first noun stays bare
• the second noun takes a possessive-looking ending

That does not mean actual possession in the English sense. It is just how Turkish forms many compound nouns.

Compare:

• jant teli = rim spoke / spoke of a rim
• jantın teli = the rim's spoke or the spoke of the rim
  This version is more explicitly possessive.

No. In this sentence, it is not accusative.

Here:

• tel + i → teli
• göbek + i → göbeği

That -i is the ending used in the noun compound structure, not the direct-object marker.

This is especially important in teker göbeği yeniden kontrol edildi:

• teker göbeği is the subject of the passive verb kontrol edildi
• it is not an accusative object

So even though göbeği looks like it might be an object, here it is just part of the compound noun.

This is due to consonant softening.

The word is:

• göbek = hub / navel / center

When a vowel-initial suffix is added, final k often softens to ğ:

• göbek
  • -i → göbeği

This is very common in Turkish:

• kitap → kitabı
• renk → rengi
• göbek → göbeği

So göbeği is exactly what you would expect from normal sound changes.

Because Turkish often uses a noun + etmek combination to make verbs.

Here:

• kontrol = check / inspection
• kontrol etmek = to check / to inspect

Then the passive form is:

• kontrol edilmek = to be checked

And in the past tense:

• kontrol edildi = was checked

So the end of the sentence means:

• teker göbeği yeniden kontrol edildi = the wheel hub was checked again

This kind of structure is very common in Turkish:

• test etmek = to test
• tamir etmek = to repair
• kontrol etmek = to inspect/check

Because Turkish uses the passive very naturally when the doer is unknown, obvious, or unimportant.

In this sentence:

• sıkıldıktan sonra = after it was tightened
• kontrol edildi = it was checked

The agent is simply left out.

This is extremely common in technical instructions, reports, and manuals, where the important thing is the procedure, not the person performing it.

If you wanted to mention the agent, you could do so, for example:

• Jant teli sıkıldıktan sonra teker göbeği teknisyen tarafından yeniden kontrol edildi.
• After the spoke was tightened, the wheel hub was checked again by the technician.

But the original sentence sounds more natural for a technical context.

Yeniden means again or anew.

So:

• yeniden kontrol edildi = was checked again

Yes, tekrar could also often be used:

• tekrar kontrol edildi

In many contexts, both are possible. Very roughly:

• yeniden can sound a bit more neutral, formal, or procedural
• tekrar is also very common in everyday Turkish

In a technical sentence like this, yeniden fits very well.

The word order is very natural for Turkish:

• Jant teli sıkıldıktan sonra = time clause first
• teker göbeği yeniden kontrol edildi = main clause after it

A very common Turkish pattern is:

• [After X happened], Y happened.

So the sentence is arranged as:

1. first action: the spoke was tightened
2. second action: the hub was checked again

Turkish word order is flexible, but this order is clear and standard, especially in technical or procedural writing.

Because Turkish does not have a definite article like English the.

So Turkish often leaves definiteness to be understood from:

• context
• word structure
• sentence meaning

In this sentence, English naturally says:

• the spoke
• the wheel hub

But Turkish simply says:

• jant teli
• teker göbeği

because the context already makes them identifiable.

If Turkish wants to say a/an, it can use bir, but that is not needed here.

So the absence of a word for the is completely normal.