CB450K5 Engine makeover, Transmission Redux Help!
Close

CB450K5 Engine makeover, Transmission Redux Help!

This is a discussion on CB450K5 Engine makeover, Transmission Redux Help! within the Technical forums, part of the Caferacer.net Forums category; I bought this bike assembled, but not really running. The carbs were filthy. The previous owner told me that it was not shifting well. He ...

Page 1 of 2 12 LastLast
Results 1 to 10 of 11
  1. #1
    WhiteFox50's Avatar
    Join Date
    Jun 2008
    Posts
    25

    CB450K5 Engine makeover, Transmission Redux Help!

    I bought this bike assembled, but not really running. The carbs were filthy. The previous owner told me that it was not shifting well. He said it would grind gears, and maybe even pop out of gear? I forget. Anyways I took apart the cases to inspect the transmission and everything looks OK from what I see. The shift forks are the only thing I could see that would cause a shifting problem.

    How do they look? What should I be looking for as far as these forks go, or anything else inside the case?



  2. #2
    Senior Member pampadori's Avatar
    Join Date
    May 2007
    Location
    Richmond, Va., USA.
    Posts
    1,523
    i thought the 5 speeds were good to go. maybe clutch causing it? do the forks look bent at all to you?
    http://www.slingshotcycles.com
    Stainless braided brake lines and other odds and ends.
    Enter coupon code "caferacer" during checkout for 15% off

  3. #3
    WhiteFox50's Avatar
    Join Date
    Jun 2008
    Posts
    25
    they do not look bent, all i see is normal wear. the clutch cable is original, maybe not fully disengaging from a stretched cable, and lack of knowledge to know that?

  4. Remove Advertisements
    CafeRacer.net
    Advertisements
     

  5. #4
    FR
    FR is offline
    Senior Member FR's Avatar
    Join Date
    Nov 2004
    Location
    Essex Jct, VT, USA.
    Posts
    2,595
    Not to sound smarmy or righteous, but the cardinal rule when trying to repair something that someone else is experiencing is to verify the complaint! You've done a lot of work to not know what you're looking for. If you had planned on splitting the cases anyway, you still should have tried to get the engine running and checked for any other issues, noises etc.
    FR


    http://sidewaysnortheast.blogspot.com/

  6. #5
    WhiteFox50's Avatar
    Join Date
    Jun 2008
    Posts
    25
    I did have it running, however it wouldn't rev up when given throttle. The carbs need a lot of work. The engine sounded and seemed to run fine while it could. I wanted to take it apart and make sure everything is nice and clean. It looks like theres some water and oil sludge at the bottom of the case too. I want to get this bike running perfectly.

  7. #6
    Senior Member craig641's Avatar
    Join Date
    Oct 2005
    Location
    Newark Valley, NY, Burkina Faso (Upper.
    Posts
    4,508
    You see those circular wear pattern on the base of the open area of the shift fork? Those are caused by the gears either not engaging completely or trying to disengage from the mating gear. The forks are only part of the problem, or the result of the real problem which most likely is worn dogs on the gears themselves. You need to remove the gear sets and replace gears with worn dogs.

    Craig

  8. #7
    buckandaquarter's Avatar
    Join Date
    Sep 2008
    Posts
    720
    Check the gear dogs to see if they are perfectly square or if they have ramps or rounds worn on them. Check your shift drum for worn tracks. Check your shift forks for bends on a flat surface. Check your shift star, springs, and follower for wear. Hope you are not new to working on stuff and have lots of time. Basically your choices are to check every single part or replce them all.

  9. #8
    WhiteFox50's Avatar
    Join Date
    Jun 2008
    Posts
    25
    Thanks guys! I do have time to work on it, the engines are just sitting in my bedroom and when I have time I work on them. I will look at everything more closely. I don't know if I will get this bike on the road this year. No rush though because I have another.

  10. #9
    Moderator jbranson's Avatar
    Join Date
    Feb 2004
    Location
    , , South Sandwich Islan.
    Posts
    11,267
    Also check the pins that locate the forks into the shift drum grooves. If they show any ridges at all then the forks probably have significant wear too. Sometimes it's hard to spot simple wear on the forks without a new one to compare it with.
    Worn/rounded dogs can usually be cleaned up with a hand file and some patience.
    JohnnyB

    PS. the fork in the last photo looks iffy. Looks like the pad that contacts the gear is quite worn, and there looks to be some signs of heat on that fork. Usually the pads should stand off from the forks a bit...those look worn down almost to the fork leg.

    PSS. BuckandaQuarter mentions something very important..the shift detent "star" and detent mechanism...most shift problems I've found on Hondas come from this area of the gear box. Roller slipped off the star, weak spring, worn pin in the detent roller (if it has one). etc.


  11. #10
    WhiteFox50's Avatar
    Join Date
    Jun 2008
    Posts
    25
    Would it be a bad idea to spot weld the tabs and file/polish them flat till they fit between the gears? I don't think I'm going to find a new set. I have another engine im waiting to open up because I was told it shifted better than this one, in fact I think he said it had no shifting problems, it just didn't run good. I was planning on swapping the transmissinos, but I could probably just take the best parts from both and make one good one.

Page 1 of 2 12 LastLast

Sponsored Links

Posting Permissions

  • You may not post new threads
  • You may not post replies
  • You may not post attachments
  • You may not edit your posts
  •  

Similar Threads

  1. Transmission question...
    By TheGreg in forum General
    Replies: 28
    Last Post: 08-22-2012, 11:56 AM
  2. CB450K5 wrist pin diameter.....
    By Swagger in forum General
    Replies: 3
    Last Post: 08-12-2009, 06:49 PM
  3. Manx Vintage GP redux w/ photos
    By ROSKO in forum Vintage Motorcycle Racing
    Replies: 1
    Last Post: 09-18-2007, 12:07 AM
  4. Electronic Ignition for '73 CB450K5?
    By teighlor in forum Technical
    Replies: 5
    Last Post: 06-23-2007, 12:17 AM
  5. RS 125 transmission oil
    By aaron in forum Technical
    Replies: 12
    Last Post: 05-10-2005, 09:40 PM

Search tags for this page

cb 450 shift drum follower

,

cb450 k5 tranny problems

Click on a term to search for related topics.