« previous next »
Pages: [1]   Go Down

Author Topic: Accessing the gear box  (Read 1263 times)

0 Members and 3 Guests are viewing this topic.

Offline Canucklehead

  • Full Member
  • *
  • Posts: 16
Accessing the gear box
« on: March 06, 2012, 06:03:37 PM »
I just bought an old CB750 K5 which has a gear box issue (won't go into second and has a whooshing noise from the gearbox) is it possible to get into the gearbox from underneath; that is take the engine out of the frame, have it upside down (drain the oil etc before this obviously) and get into the gear box without upsetting the upper end? The top end is in good shape and doesn't have any issues. Can I do it this way or am I stuck doing a full tear down?
Logged

Offline Pecantree

  • Hot Shot
  • ***
  • Posts: 447
Re: Accessing the gear box
« Reply #1 on: March 06, 2012, 06:20:35 PM »
Shh! Don't upset the upper end! >:(

Yes you can.
CycleX sells a undercut tranny you can swap out or buy one on ebay.
Check your shift forks too.
Good luck :)
Logged
http://www.harvestclassic.org/

"The suspect had experienced a ballistic interlude earlier in the evening" Miss Pao said, "Regrettably not filmed, and relived himself of excess velocity by means of an ablative technique."         ......    ?    ........         "She say you have road rash."

Offline cbr954

  • Hot Shot
  • ***
  • Posts: 402
Re: Accessing the gear box
« Reply #2 on: March 06, 2012, 06:32:24 PM »
Yes with the engine out of the frame you can split the cases without doing anything to the top end.
Logged
03 CBR954RR, 72 750 chopper(970cc
F2 head), 2017 CRF450R, 2001 CR250R, 72 CB500, 79 XR250, 04 CRF50,70's soon to be rebuilt cb750 drag bike.

Offline Canucklehead

  • Full Member
  • *
  • Posts: 16
Re: Accessing the gear box
« Reply #3 on: March 06, 2012, 07:11:38 PM »
Thanks for the replies, I guess I'll turn it upside down and attack from the rear  ;)
Logged

Offline scottly

  • Global Moderator
  • Really Old Timer ...
  • *****
  • Posts: 16,389
  • Humboldt, AZ
Re: Accessing the gear box
« Reply #4 on: March 06, 2012, 07:29:27 PM »
Before you pull the motor and split the cases, you may want to pull the shifter cover off the left side of the motor, and check out the shift linkage and the end of the shift drum. ;)
Logged
Don't fix it if it ain't broke!
Helmets save brains. Always wear one and ride like everyone is trying to kill you....

Offline Canucklehead

  • Full Member
  • *
  • Posts: 16
Re: Accessing the gear box
« Reply #5 on: March 06, 2012, 08:57:01 PM »
Thanks Scotty, that was the first part of the plan, I'm just trying to think ahead a bit.  :)
Logged

Offline scottly

  • Global Moderator
  • Really Old Timer ...
  • *****
  • Posts: 16,389
  • Humboldt, AZ
Re: Accessing the gear box
« Reply #6 on: March 06, 2012, 09:04:15 PM »
Do the easy stuff first! ;) (just where in BC are you? You may be in close proximity to a real expert or two..)
Logged
Don't fix it if it ain't broke!
Helmets save brains. Always wear one and ride like everyone is trying to kill you....

Offline Canucklehead

  • Full Member
  • *
  • Posts: 16
Re: Accessing the gear box
« Reply #7 on: March 06, 2012, 10:07:04 PM »
I'm in Merritt, fairly close to Kelowna and Kamloops. Next to some of the best motorbike roads in BC  :)
Logged

Offline scottly

  • Global Moderator
  • Really Old Timer ...
  • *****
  • Posts: 16,389
  • Humboldt, AZ
Re: Accessing the gear box
« Reply #8 on: March 07, 2012, 08:23:17 PM »
Quote from: Canucklehead on March 06, 2012, 10:07:04 PM
I'm in Merritt, fairly close to Kelowna and Kamloops. Next to some of the best motorbike roads in BC  :)
Kelowna, huh? Seems I've heard of that place somewhere... ;)
Logged
Don't fix it if it ain't broke!
Helmets save brains. Always wear one and ride like everyone is trying to kill you....

Offline Canucklehead

  • Full Member
  • *
  • Posts: 16
Re: Accessing the gear box
« Reply #9 on: March 18, 2012, 05:01:01 PM »
Looks like my problem may be a worn stopper shift drum, it shows quite a lot of wear and doesn't lock into the gear detents well possible due to the wear creating a little less tension on the spring? I'll replace this first and see what happens. When I moved the drum and wiggled the rear tires the gears all moved nicely, no catch for now. Hopefully this is a cheap fix.
Canucklehead.
Logged
Pages: [1]   Go Up
« previous next »