i want to create field where countinues count

i have field

odometer_pasang = fields.Integer(string='Odometer Pemasangan Sebelumnya')
odometer_tire = fields.Integer(string='Odometer Tire', compute='_compute_odometer_tire')
odometer_pengecekan = fields.Integer(string='Odometer Pengecekan')
odometer_cek = fields.Integer(string='KM Pemasangan - KM Pengecekan', compute='_compute_odometer_cek')

@api.depends('odometer_pengecekan','odometer_pasang')
def _compute_odometer_cek(self):
    for r in self:
        if r.odometer_pengecekan and r.odometer_pasang:
                r.odometer_cek = r.odometer_pengecekan - r.odometer_pasang

@api.depends('odometer_pengecekan','odometer_pasang')
def _compute_odometer_tire(self):
    for r in self:
        tampung = r.odometer_pengecekan - r.odometer_pasang
        r.odometer_tire += tampung


i want to make field odometer_tire always count from odometer_cek but for now odometer_tire not counting sum