Fren balatası dış lastiğe değmiyor.

Because fren balatası is a very common Turkish noun-compound pattern called an indefinite noun compound.

• fren = brake
• balata = pad / lining
• fren balatası = brake pad

In this pattern, the second noun usually takes a 3rd person possessive ending:

• araba kapısı = car door
• okul bahçesi = school yard
• fren balatası = brake pad

So even though English just puts two nouns together, Turkish often marks the second noun this way.

Because the verb değmek takes the dative case, which usually corresponds to to in English.

So:

• lastik = tire
• lastiğe = to the tire

With değmek, Turkish says something like to touch/contact something using the dative:

• duvara değmek = to touch the wall
• elime değdi = it touched my hand
• dış lastiğe değmiyor = it is not touching the outer tire

So the -e / -a ending is required by the verb.

This is a spelling and sound change that happens in Turkish.

The base word is:

• lastik

When you add the dative ending -e, the final k often changes to ğ in many words:

• lastik + e → lastiğe
• renk + e → renge
• kulak + a → kulağa

Also, notice that the second syllable vowel shifts in the written form:

• lastik → lastiğe

This is normal and something you will see a lot in Turkish.

Değmiyor comes from the verb değmek = to touch, to come into contact with.

It breaks down like this:

• değ- = touch
• -mi- = negative part
• -yor = present continuous / current situation

So:

• değiyor = is touching
• değmiyor = is not touching

In natural English, this can mean:

• is not touching
• isn’t making contact with

Depending on context, it can also sound like doesn’t touch.

Because the negative suffix is -ma / -me, but before -yor it changes form in practice.

Compare:

• gelmek → gelmiyor = is not coming
• yapmak → yapmıyor = is not doing
• değmek → değmiyor = is not touching

So although learners often expect something like değmeyor, the correct form is değmiyor. This is a regular pattern with -iyor in the negative.

Turkish does not have articles like English a/an and the.

So a noun like fren balatası can mean:

• a brake pad
• the brake pad

And dış lastiğe can mean:

• to an outer tire
• to the outer tire

You understand which one is meant from context.

Dış means outer, outside, or external.

So:

• dış lastik = outer tire

This is especially natural in contexts like bicycles or wheels, where you may distinguish between an outer tire and an inner tube.

Some useful contrasts:

• dış = outer / external
• iç = inner / internal

For example:

• dış kapı = outer door
• iç lastik = inner tube

This is a very normal Turkish word order.

A common Turkish sentence pattern is:

subject + object/complement + verb

So here:

• Fren balatası = subject
• dış lastiğe = complement required by the verb
• değmiyor = verb

Turkish usually puts the verb at the end, much more often than English does.

You could change the order for emphasis, but this version is the most neutral and natural.

No. Değmek can be used both literally and figuratively.

Literal:

• Masa duvara değiyor. = The table is touching the wall.

Figurative:

• Bu konu bana değmiyor. = This matter does not concern me.
• Onun sözleri bana çok değdi. = His/her words affected me deeply.

In your sentence, it is the literal, physical meaning: to touch / make contact with.

Yes, but the meaning would change slightly.

• değmiyor = is not touching / isn’t making contact right now, or in the current situation
• değmez = does not touch / won’t touch / doesn’t normally touch

So:

• Fren balatası dış lastiğe değmiyor.
  This sounds like a current state or observed situation.

• Fren balatası dış lastiğe değmez.
  This sounds more general, habitual, or technical: the brake pad does not touch the outer tire.

In many practical contexts, değmiyor is the more natural choice when describing what you are seeing.

It is singular:

• fren balatası = brake pad

If you wanted plural, you would usually say:

• fren balataları = brake pads

In Turkish, plural is only added when needed. If context already makes the number clear, Turkish sometimes leaves nouns singular where English might use plural.