PhpSQL/VB help with code

Hi, trying to update my phpsql database after this code:

Try
For Each itemChecked In Sykkel.clistterreng.CheckedItems
ListBoxvarer.Items.Add(quote + itemChecked.ToString() + quote)
conn.Open()
Dim sqlUpdate As New MySqlCommand("UPDATE Sykkel SET leidut = 1 WHERE CONCAT(sykkel_nr, ' ', sykkel_type) = '" & itemChecked & "'", conn)
Dim adapter As New MySqlDataAdapter
Dim tabell As New DataTable

adapter.SelectCommand = sqlUpdate
adapter.Fill(tabell)

conn.Close()
Dim rad As DataRow
Dim utleid As String
For Each rad In tabell.Rows
utleid = rad("leidut")
Next rad
Next
catch ex As Exception
MsgBox("Noe gikk feil git")

End Try

Can anyone see what's wrong here? If I change the sql sentence to:
Dim sqlUpdate As New MySqlCommand("UPDATE Sykkel SET leidut = 1", conn)

It works, but updates the whole table. When I try my sentence in the actual sql website (myphpadmin) that sentence with CONCAT works perfectly :S

EDIT:
I see that items.checked makes the string come out like this "a001 terrengsykkel", when i want it to just go: a001 terrengsykkel

The thing is, if i change the code to:
Dim sqlUpdate As New MySqlCommand("UPDATE Sykkel SET leidut = 1 WHERE CONCAT(sykkel_nr, ' ', sykkel_type) = itemChecked, conn)
It should work in theory, atelast the SQL sentence works, but I get an error in VB.

What is a phpsql database? Never heard of it.

Haha sorry, SQL

Basicly, can anyone see the difference between these two?

SQL:
UPDATE Sykkel
SET leidut = 0
WHERE CONCAT(sykkel_nr, ' ', sykkel_type) = "a001 Terrengsykkel"

VB:
Dim sqlUpdate As New MySqlCommand("UPDATE Sykkel SET leidut = 1 WHERE CONCAT(sykkel_nr, ' ', sykkel_type) = " & " " & itemChecked, conn)

EDIT:
itemChecked values "a001 Terrengsykkel"

SQL is not the name of a database management system either. SQL is the name of the scripting language used by most database systems.

Use the debugger to see if your sql from vb code is the same as your manual sql.