« previous next »
Pages: [1] 2 3   Go Down

Author Topic: Bike popping out of gear? Update!  (Read 6909 times)

0 Members and 3 Guests are viewing this topic.

Offline 75 super sport

  • Hot Shot
  • ***
  • Posts: 263
Bike popping out of gear? Update!
« on: April 03, 2016, 02:35:02 PM »
Well after 5 years of building this piggy (1975 cb750f) I took her for the first spin today. She is popping out ofgear. I only got up to 2nd but did it in both 1st and second. Any ideas would be amazing.  Thank you
« Last Edit: April 07, 2016, 06:31:27 PM by 75 super sport »
Logged
"Smoke em if ya got em"

Offline goldarrow

  • one day, i'll be an
  • Old Timer
  • ******
  • Posts: 3,361
Re: Bike popping out of gear?
« Reply #1 on: April 03, 2016, 02:49:36 PM »
Worn gear forks and drum


Sent from my iPhone using Tapatalk
Logged
Life Is Full Of Challenges - And My Backyard Is Full Of SOHC4's

CB550 K0
CB750 K0, K2, K23 JDM, K45, K5
And the little ones z50r, xr50r, st90


750k5 http://forums.sohc4.net/index.php?topic=114817.0

Offline 75 super sport

  • Hot Shot
  • ***
  • Posts: 263
Re: Bike popping out of gear?
« Reply #2 on: April 03, 2016, 03:08:14 PM »
Really? This is horrible news. It couldn't be something as simple as clutch adjustment?
Logged
"Smoke em if ya got em"

Offline 75 super sport

  • Hot Shot
  • ***
  • Posts: 263
Re: Bike popping out of gear?
« Reply #3 on: April 03, 2016, 03:14:57 PM »
The bike only has 13,000 original miles too
Logged
"Smoke em if ya got em"

Offline 75 super sport

  • Hot Shot
  • ***
  • Posts: 263
Re: Bike popping out of gear?
« Reply #4 on: April 03, 2016, 04:45:02 PM »
anyone who has been through an issue similar to this? How long would it take to replace shift forks and drum? What years will be compatible with the 75cb750f?
Logged
"Smoke em if ya got em"

Offline scottly

  • Global Moderator
  • Really Old Timer ...
  • *****
  • Posts: 16,269
  • Humboldt, AZ
Re: Bike popping out of gear?
« Reply #5 on: April 03, 2016, 05:59:49 PM »
More information is required. What is the history of the bike? Is this the first time you have ridden it? What has been taken apart? Did it pop out of gear when under hard acceleration? Don't panic yet.. ;)
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 75 super sport

  • Hot Shot
  • ***
  • Posts: 263
Re: Bike popping out of gear?
« Reply #6 on: April 03, 2016, 06:31:24 PM »
History of bike: the bike sat for 12 years. I purchased the bike 5 years ago. I have been building it ever since. It has 13,000 original mikes, and in the inside of the top end looked brand new. Did an 836 top end rebuild, did not mess with bottom end. This is the first time I have ridden it. It pops out of gear even at very light load. I took apart clutches to clean them and reassembled them. The clutch cable adjustment bolt on the clutch side is all the way out ( only a couple threads into clutch cover). Clutch actuator set screw is all the way in, 1/8th turn out. Let me know if you need any other information.
Logged
"Smoke em if ya got em"

Offline scottly

  • Global Moderator
  • Really Old Timer ...
  • *****
  • Posts: 16,269
  • Humboldt, AZ
Re: Bike popping out of gear?
« Reply #7 on: April 03, 2016, 06:35:35 PM »
Did you have the shifter cover removed?
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 scottly

  • Global Moderator
  • Really Old Timer ...
  • *****
  • Posts: 16,269
  • Humboldt, AZ
Re: Bike popping out of gear?
« Reply #8 on: April 03, 2016, 06:37:52 PM »
Does the neutral light work properly?
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 75 super sport

  • Hot Shot
  • ***
  • Posts: 263
Re: Bike popping out of gear?
« Reply #9 on: April 03, 2016, 06:44:57 PM »
I did have the cover off to replace the final drive sprocket. I am no longer utilting the neutral light
Logged
"Smoke em if ya got em"

Offline 75 super sport

  • Hot Shot
  • ***
  • Posts: 263
Re: Bike popping out of gear?
« Reply #10 on: April 03, 2016, 06:47:44 PM »
I guess that wouldnt be the cover you were referring to would it? Lol
Logged
"Smoke em if ya got em"

Offline madmtnmotors

  • When did I get to be a
  • Really Old Timer ...
  • *******
  • Posts: 6,090
  • Sunny Central Florida
Re: Bike popping out of gear?
« Reply #11 on: April 03, 2016, 06:48:18 PM »
Quote from: 75 super sport on April 03, 2016, 06:31:24 PM
Clutch actuator set screw is all the way in, 1/8th turn out.

This sounds disturbing. The clutch "actuator", or "lifter" should be adjusted as follows:

>Loosen the locknut and turn the actuator adjustment out until there is no load
>Slowly turn the adjuster screw in until it just touches the throwout bearing. Then back off 1/8 to 1/4 turn. If you go past the point of engagement then you are disengaging the clutch. I have done this more than once, it is easy to go too far.
>Then adjust cable slack.
Logged
TAMTF...


Wilbur



Projects:
"Evolution": http://forums.sohc4.net/index.php?topic=100352.0
"P.O. Debacle": http://forums.sohc4.net/index.php/topic,126692.msg1441661.html#msg1441661
F2/F3 O-rings: http://forums.sohc4.net/index.php?topic=113672.msg1300721#msg1300721
Cam Tower Studs: https://www.mcmaster.com/#93210a017/=t19sgp
Clean up that nasty harness: http://forums.sohc4.net/index.php?topic=137351.msg1549191#msg1549191
http://forums.sohc4.net/index.php/topic,148188.msg1688494.html#msg1688494
http://forums.sohc4.net/index.php/topic,139544.msg1579364.html#msg1579364
                                          
Charging system diagnosis: http://forums.sohc4.net/index.php?topic=1012.msg8345#msg8345
Get the manuals: http://manuals.sohc4.net/cb750k/
The Dragon: http://forums.sohc4.net/index.php?topic=45183.msg1571675#msg1571675
Headlight Switch: http://forums.sohc4.net/index.php?topic=113986.msg1283236#msg1283236
Branden's leak free top end thread: http://forums.sohc4.net/index.php?topic=107040.0
Engine Lifting Made Easy: http://forums.sohc4.net/index.php/topic,58210.msg1684742.html#msg1684742
                                      http://forums.sohc4.net/index.php/topic,100352.msg1675840.html#msg1675840
Static and Dynamic Timing: http://www.hondachopper.com/garage/carb_info/timing/timing1.html
Airbox Gasket Replacement: http://forums.sohc4.net/index.php/topic,114485.msg1290000.html#msg1290000
"Café" : http://forums.sohc4.net/index.php/topic,84697.msg953814.html#msg953814
PD Carb Choke Linkage: http://forums.sohc4.net/index.php/topic,100352.msg1669248.html#msg1669248
                                    http://forums.sohc4.net/index.php/topic,110931.msg1248354.html#msg1248354
                                    http://forums.sohc4.net/index.php/topic,48858.msg515204.html#msg515204
Follow up on your damn posts: http://forums.sohc4.net/index.php/topic,144305.msg1791605.html#msg1791605
Taiwanese Cam Chain Tensioners:  http://forums.sohc4.net/index.php/topic,155043.msg1774841.html#msg1774841
Gumtwo Seat Cover: http://forums.sohc4.net/index.php/topic,164440.msg1897366.html#msg1897366
Primary Drive: http://forums.sohc4.net/index.php/topic,166063.msg1919278.html#msg1919278
Tank Latch: http://forums.sohc4.net/index.php/topic,165975.msg1919495.html#msg1919495
Shorten your forks: http://vintage-and-classic-honda-s.456789.n3.nabble.com/How-to-shorten-forks-td4042465.html DO NOT CUT THE SPRINGS!
Clutch How To: http://vintage-and-classic-honda-s.456789.n3.nabble.com/How-to-change-and-adjust-a-clutch-SOHC-td4040391.html
Late model K7/K8/F2/F3 front sprocket cover removal: http://forums.sohc4.net/index.php/topic,178428.msg2072279.html#msg2072279
630 to 530 conversion: http://forums.sohc4.net/index.php/topic,180710.msg2094423.html#msg2094423

Sent from my Tandy TRS-80!

Offline scottly

  • Global Moderator
  • Really Old Timer ...
  • *****
  • Posts: 16,269
  • Humboldt, AZ
Re: Bike popping out of gear?
« Reply #12 on: April 03, 2016, 06:52:55 PM »
Did you try to shift to 3rd?
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 75 super sport

  • Hot Shot
  • ***
  • Posts: 263
Re: Bike popping out of gear?
« Reply #13 on: April 03, 2016, 06:53:42 PM »
That's what I meant, I apologize. The set screw was all the way out, screwed in until it just touches the throwout bearing, then back out 1/8 - 1/4 turn
Logged
"Smoke em if ya got em"

Offline 75 super sport

  • Hot Shot
  • ***
  • Posts: 263
Re: Bike popping out of gear?
« Reply #14 on: April 03, 2016, 06:54:30 PM »
I did not try to shift it to 3rd
Logged
"Smoke em if ya got em"

Offline scottly

  • Global Moderator
  • Really Old Timer ...
  • *****
  • Posts: 16,269
  • Humboldt, AZ
Re: Bike popping out of gear?
« Reply #15 on: April 03, 2016, 07:04:36 PM »
So, as far as you know, the shifter cover and the neutral switch haven't been messed with?
Can you take a pic of the external shifter lever?
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 75 super sport

  • Hot Shot
  • ***
  • Posts: 263
Re: Bike popping out of gear?
« Reply #16 on: April 03, 2016, 07:08:50 PM »
Yes, as far as I know they have not been messed with. The bike is in a friend's garage so I am not able to take a picture of the external shift lever at the moment. I did use a shift lever from a 1978 cb750f, I don't know if that makes any difference
Logged
"Smoke em if ya got em"

Offline scottly

  • Global Moderator
  • Really Old Timer ...
  • *****
  • Posts: 16,269
  • Humboldt, AZ
Re: Bike popping out of gear?
« Reply #17 on: April 03, 2016, 07:15:03 PM »
I don't know the difference, if any, but at this point it's something to keep in mind...
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 75 super sport

  • Hot Shot
  • ***
  • Posts: 263
Re: Bike popping out of gear?
« Reply #18 on: April 03, 2016, 07:17:47 PM »
The only thing I noticed when installing that shift lever was that if I pushed the lever all the way to the case, the bolt that screws through the lever wouldn't clear the shaft, so I had to back the lever off just a bit so the bolt would go all the way through
Logged
"Smoke em if ya got em"

Offline 75 super sport

  • Hot Shot
  • ***
  • Posts: 263
Re: Bike popping out of gear?
« Reply #19 on: April 03, 2016, 08:07:34 PM »
Is anything coming to your head scottly?
Logged
"Smoke em if ya got em"

Offline Kickstart

  • Expert
  • ****
  • Posts: 796
Re: Bike popping out of gear?
« Reply #20 on: April 03, 2016, 08:15:29 PM »
Can you provide a detailed description of the popping out of gear situation?

i.e., does it shift fine into gear and you can drive for a few minutes and then it pops out, or does it pop out of gear immediately?  Popping out under heavy throttle, or any time, etc.

Logged
- Chris
75' CB750F Orange flake (rider)
75' CB750F Blue (Project)
75' CB750F Painted black (Project)
No Reserve Racing #171 AHRMA

Offline goldarrow

  • one day, i'll be an
  • Old Timer
  • ******
  • Posts: 3,361
Re: Bike popping out of gear?
« Reply #21 on: April 03, 2016, 08:19:04 PM »
Only split the cases to Change the shift forks and drum, top end doesn't have to come apart. 


Sent from my iPhone using Tapatalk
Logged
Life Is Full Of Challenges - And My Backyard Is Full Of SOHC4's

CB550 K0
CB750 K0, K2, K23 JDM, K45, K5
And the little ones z50r, xr50r, st90


750k5 http://forums.sohc4.net/index.php?topic=114817.0

Offline 75 super sport

  • Hot Shot
  • ***
  • Posts: 263
Re: Bike popping out of gear?
« Reply #22 on: April 03, 2016, 08:26:55 PM »
It pops out almost immediately, under any throttle condition.
Logged
"Smoke em if ya got em"

Offline 75 super sport

  • Hot Shot
  • ***
  • Posts: 263
Re: Bike popping out of gear?
« Reply #23 on: April 03, 2016, 08:28:30 PM »
It seems to shift fine into gear, can find neutral easy. I tried holding the lever down into first while acceleration and it still popped out
Logged
"Smoke em if ya got em"

Offline scottly

  • Global Moderator
  • Really Old Timer ...
  • *****
  • Posts: 16,269
  • Humboldt, AZ
Re: Bike popping out of gear?
« Reply #24 on: April 03, 2016, 08:40:29 PM »
Quote from: 75 super sport on April 03, 2016, 08:07:34 PM
Is anything coming to your head scottly?
Two things come to mind:
1. You are not fully shifting the bike into gear.
2. I hesitate to post this, but perhaps the reason the bike sat unused for so long was due to the same shifting problem. Some bikes came from Honda with improperly installed snap rings on the transmission shafts, which could pop out of their grooves and allow erratic transmission operation. I was unfortunate to have one of these, which decided to shift into gear by itself while cranking the motor, folding up the kick-stand and falling on top of me. The fix was to split the cases and re-install the snap rings in the proper direction. Hopefully your problem is #1.  ;)
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....
Pages: [1] 2 3   Go Up
« previous next »