Suzuki DF2.5 Service Manual page 80

REASSEM
Reassembly is reverse order of disassembly with the special
attention to the following steps.
1. Apply engine oil to the valve stem seals
2. Install the valve stem seals to the valve guide.
3. Apply engine oil to the valve guide bore and valve stem.
4. Install the valve (2) to the valve guide.
5. Install the valve spring@ and the retainer
NOTE:
Reassemble each valve spring to their original position.
6. Push down the retainer with both thumbs to admit the valve
stem into the side hole of the retainer, and let it slide side-
wise into the center hole.
7. Make sure the retainers are properly seated in groove
POWER UNIT 6-17