Author Topic: Unlocking the seat  (Read 173 times)

Offline garyb163

  • Newbie
  • Posts: 10
    • View Profile
Unlocking the seat
« on: February 12, 2018, 03:46:58 PM »
Hi guys, My CB550F2 1977 only has one key. It operates the ignition and the fuel filler flap but it won't open the lock to gain access to the under seat any ideas as to how I can gain access?

Offline SteveW

  • SOHC Associate
  • Posts: 93
    • View Profile
Re: Unlocking the seat
« Reply #1 on: February 12, 2018, 04:54:55 PM »
Just had a look at mine (74 K0).

You wont be able to get at the lock easily as its bolted to the frame under the seat.

What might be possible is if you feel upwards towards the seat, either side of the seat plunger that engages with the lock there are 2 10mm nuts that bolt the plunger to the seat. I think with a small ratchet you can get at them.
1974 CB550 K0
2000 CBR929RR Fireblade
1966 Lambretta LI150 Series 3

Offline garyb163

  • Newbie
  • Posts: 10
    • View Profile
Re: Unlocking the seat
« Reply #2 on: February 12, 2018, 06:07:40 PM »
Thanks SteveW I'll give that a go tonight.

Offline petermigreen

  • SOHC Expert
  • Posts: 331
    • View Profile
Re: Unlocking the seat
« Reply #3 on: February 12, 2018, 06:30:10 PM »
Does the seat lock not have a number on it? Usually a 4 digit number adjacent to the key slot. If it does you can either confirm it's the same as the other locks or order the correct one.
Peter
1944 42WLA
1973 CB500K2 USA
1975 CB400F0 USA
1976 DT175C
1982 RD200F

Offline garyb163

  • Newbie
  • Posts: 10
    • View Profile
Re: Unlocking the seat
« Reply #4 on: February 12, 2018, 08:12:38 PM »
Hi Petermigreen, I've checked and there are definitely no numbers on the lock or any where near it. The one key I have fits both the ignition and fuel cap locks. The same key fits in the seat lock barrel but won't turn. Do you think as I do that some one at some stage has fitted a new seat lock? If so I wonder why?

Offline Bryanj

  • SOHC Jedi
  • Posts: 4657
    • View Profile
Re: Unlocking the seat
« Reply #5 on: February 13, 2018, 06:53:09 AM »
More likely a new ignition switch, any key(including a screwdriver) will open the fuel cap lock

Offline Oddjob

  • SOHC Master
  • Posts: 2333
    • View Profile
Re: Unlocking the seat
« Reply #6 on: February 13, 2018, 01:26:03 PM »
You could try removing the hinge pins on the opposite side, remove the 2 split pins, don't lose them, then the 2 small washers and knock the pins out. This will allow the seat to raise up a bit and you should be able to get a 10mm spanner on the 2 nuts holding the seat lock plunger in place. Once the seat is off, remove the 2 screws holding the lock in place and you should be able to use a small screwdriver to flick the locking bar back to allow the plunger to be removed.

The lock number should be on the upper side of the lock, it's hidden by the frame plate so thieves can't just look and order a key, next to the small locking bar you've flicked back.
Don't play stupid with me, I'm better at it