Bisiklet bakımı tamir standında başladı.

A rough breakdown is:

• bisiklet = bicycle
• bakım-ı = maintenance, in a compound form
• tamir stand-ı-n-da = on/in/at the repair stand
• başladı = started / began

So the sentence structure is basically:

[subject] + [location] + [verb]

This is very normal in Turkish, especially with the verb at the end.

Because bisiklet bakımı is a common Turkish noun compound meaning bicycle maintenance.

In this pattern:

• the first noun stays bare: bisiklet
• the second noun takes a suffix: bakım-ı

So:

• bakım = maintenance
• bisiklet bakımı = bicycle maintenance

This -ı is not the accusative here. It is part of the compound.

These two forms are related, but they are not the same.

• bisiklet bakımı = bicycle maintenance, as a general activity/category
• bisikletin bakımı = the maintenance of the bicycle, referring to a specific bicycle

So in your sentence, bisiklet bakımı sounds more like bike maintenance as an activity or task, not necessarily the maintenance of one particular bicycle already known in the conversation.

Yes. Bisiklet bakımı is the subject.

The verb başlamak means to start / begin, and it is normally intransitive in this use. That means there is no direct object here.

So even though bakımı ends in -ı, it is not an object. It is part of the subject phrase:

• Bisiklet bakımı = the bike maintenance
• başladı = started

This part can be broken down like this:

• tamir = repair
• standı = stand, in a compound form
• standında = on/in/at its/the stand

So:

• tamir standı = repair stand
• tamir standında = on the repair stand / at the repair stand

This is another noun compound, just like bisiklet bakımı.

That n is a buffer consonant.

The word already contains a possessive-style ending as part of the compound:

• standı = stand in compound form

When a case ending is added after that, Turkish often inserts -n- before the case suffix:

• standı + da becomes standında

This happens a lot:

• evi → evinde
• arabası → arabasında
• standı → standında

The suffix -da / -de is the locative case, and English may translate it as in, on, or at depending on context.

So tamir standında could literally be understood as location on the stand. In natural English, for this situation, on the repair stand is probably the best translation.

Turkish does not always separate in/on/at the way English does.

Başladı is the simple past tense, third person singular, from başlamak.

Breakdown:

• başla- = start / begin
• -dı = past tense

So:

• başladı = he/she/it started, or simply started

Because the subject bisiklet bakımı is singular, the verb is singular too.

Yes. Turkish word order is flexible, although the verb usually stays near the end.

Your sentence is:

• Bisiklet bakımı tamir standında başladı.

You could also say:

• Tamir standında bisiklet bakımı başladı.

Both are grammatical. The difference is mostly focus:

• starting with bisiklet bakımı highlights the activity
• starting with tamir standında highlights the location

They are related, but not identical.

• bakım = maintenance, care, servicing
• tamir = repair

So the sentence says that the maintenance activity started, and it started on the repair stand.

That makes sense: you can do maintenance on a repair stand, even if you are not fixing a specific broken part.

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

So a phrase like bisiklet bakımı can be understood in different ways depending on context:

• bicycle maintenance
• the bicycle maintenance
• bike maintenance

Likewise, tamir standında can mean on the repair stand or at a repair stand, depending on the situation. English translations usually choose whichever sounds most natural in context.