do i need to use those fields what i wanna show in that like picture and price. but anyways this code dont show in web also the categorie names aint visible in that page.

do i use it like this then:
<% control Categories %>
$CategoryName
<% control Bikes %>
<div class="pilt">
<table width="220" border="0" cellspacing="0" cellpadding="0" style="height:170; vertical-align:top; text-align:center;">
<tr>
<td height="19"><div style="text-align:center;"><strong><a href="$link" title="$Mootorrattanimi">$Mootorrattanimi</a><strong></div></td>
</tr>
<tr>
<td height="150" valign="top"><div style="text-align:center;"><a href="$link" title="$Mootorrattanimi">$Photo.Setheight(143)</a></div></td>
</tr>
</table>
</div>
<% end_control %>
<% end_control %>

Something is wrong with the function because everything else shows up the fields and stuff. Only when the fields are inside categories controller they dont show up so something is wrong with the controller code with categories.
Also categorie names dont show up

Your Categories() function doesn't return anything!!

--------------------
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its shows categories in backend but not in frontend

nothing , nada, ничего.

if <% control Bikes %> is before categories its shows the bike info but not category if its after categories its doesnt show anything. thats why i thing the function is broken.

i use also the show in dataobject maybe there is some function needed also in dataobject.

Like I said, your Categories() function doesn't return anything. That's the problem.

--------------------
SilverStripe tips, tutorials, screencasts and more: http://www.leftandmain.com

made it from your example.

Can u figure out what can be wrong

This function:

public function Categories() {
$ret = new DataObjectSet();
foreach(singleton('Bike')->dbObject('BikeCategory')->enumValues() as $cat) {
$ret->push(new ArrayData(array(
'CategoryName' => $cat,
'Bikes' => DataObject::get("Bike","BikeCategory = '$cat'")
)));
}
}

has no return..

you need to add:

return $ret;