Author Topic: 1978 CB750 K8 fuel flap query  (Read 2932 times)

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Offline martin_uk

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1978 CB750 K8 fuel flap query
« on: March 14, 2015, 03:31:21 AM »
Starting to fit up my tank and noticed that in parts book a 23 O ring is shown, but is not clear where it fits,

Any ideas?

No. 23 in diagram.

http://www.cmsnl.com/honda-cb750k-750-four-k-1978-usa_model7244/partslist/F++12.html#results

Also, does anyone know where the locks may be available No 18 pn 372203900007 or just the metal cap/cover as mine has been mangled.

I assume Honda bought in from another supplier?
CB750F1, CB750K8,  Triumph Street Triple R, AJS 350, Triumph 3TA

Offline madmtnmotors

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Re: 1978 CB750 K8 fuel flap query
« Reply #1 on: March 14, 2015, 05:14:26 AM »
Don't know about item number 23, can't imagine where that goes. Can't remember ever seeing that on mine.

As for the metal cap on the (pseudo) flap lock, I had one that was pretty mangled too. The lock can be carefully disassembled by pressing out the tiny rolled pin near the bottom of the lock assembly. Everything will slide apart at that point and the lock cylinder can be removed from the bottom of the bezel then the cap can be pulled off the top of the cylinder. Don't lose any of the little parts! I used a steel punch that very closely fit the inside diameter of this cap and a few taps on the punch with the cap face down on a vise/anvil/or any flat smooth hard surface and you'll be surprised how well it can turn out. The cap is stainless steel and much more forgiving than chrome.

Reassemble and enjoy!
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 martin_uk

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Re: 1978 CB750 K8 fuel flap query
« Reply #2 on: March 14, 2015, 05:29:15 AM »
Don't know about item number 23, can't imagine where that goes. Can't remember ever seeing that on mine.

As for the metal cap on the (pseudo) flap lock, I had one that was pretty mangled too. The lock can be carefully disassembled by pressing out the tiny rolled pin near the bottom of the lock assembly. Everything will slide apart at that point and the lock cylinder can be removed from the bottom of the bezel then the cap can be pulled off the top of the cylinder. Don't lose any of the little parts! I used a steel punch that very closely fit the inside diameter of this cap and a few taps on the punch with the cap face down on a vise/anvil/or any flat smooth hard surface and you'll be surprised how well it can turn out. The cap is stainless steel and much more forgiving than chrome.

Reassemble and enjoy!

Thanks Wilbur, that great.

Now to solve the mystery of 23mm O ring :)
CB750F1, CB750K8,  Triumph Street Triple R, AJS 350, Triumph 3TA

Offline madmtnmotors

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Re: 1978 CB750 K8 fuel flap query
« Reply #3 on: March 14, 2015, 05:46:28 AM »
Your quite welcome. I was experimenting with mine when I did this repair and was pleasantly surprised with the results. Use care when pressing on the rolled pin, plastic gets brittle with age. Make sure whatever you use to press it out is ever so slightly smaller in diameter so you don't stress the plastic by trying to push a larger pin through the hole. Try to support the backside as well while pushing on the pin. If I recall correctly it does not require a great deal of force since the pin is just pushed into plastic. No hammers!

The little key flap is separate from the cap and it has a little spring behind it. If you can leave the key flap an spring undisturbed when you pull the cap off it makes it a little easier to put back together.

I've seen at least one other post about that o-ring #23, but it's been a while and I don't know if there was ever an answer for it or if I could even find the thread even using the search function. I'm wondering if it wraps around one side of the latch bracket to suppress vibration of the fuel door? I know there's been times when I can get some buzzing from mine.
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 Restoration Fan

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Re: 1978 CB750 K8 fuel flap query
« Reply #4 on: March 14, 2015, 11:22:49 AM »
Martin, I bought a new fuel lock several months ago but I don't remember where I got it.  When I get back to the house, I'll see if I can find it on one of the invoices.
Ron

Stella - Logan's Senior Project    78 750K http://forums.sohc4.net/index.php?topic=141761.0

Logan's Reward - CB500 and CB550 Cafes    http://forums.sohc4.net/index.php/topic,147787.0.html

Offline Stev-o

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Re: 1978 CB750 K8 fuel flap query
« Reply #5 on: March 15, 2015, 12:16:37 PM »
Martin, I bought a new fuel lock several months ago but I don't remember where I got it.  When I get back to the house, I'll see if I can find it on one of the invoices.


I could not find a new one last year.  I bought the whole door on eBay just to get the lock.
'74 "Big Bang" Honda 750K [836].....'76 Honda 550F.....K3 Park Racer!......and a Bomber!............plus plus plus.........

Offline madmtnmotors

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Re: 1978 CB750 K8 fuel flap query
« Reply #6 on: March 19, 2015, 05:49:46 PM »
Okay, had to come back and post an update. It had been so long since I had worked on mine that there is one important piece of information that I had apparently forgotten. I turned my attention to my current "Evolution" project this evening and noticed the fuel door latch would benefit from the treatment described above. Looking at the latch, and the aforementioned rolled pin, it became obvious that the hole for this rolled pin does not go all the way through! Evidently I had come to the same conclusion when I did the first one that the other side of the housing would require a small hole to be able to push the pin out. Obviously Honda never expected this to be a serviceable part. Just open a small hole on the opposite side of the rolled pin, with a Dremel bit or a very small drill bit. I was able to do this by hand since the blind hole stops just short of the outside of the casing and we're only dealing with plastic here.

So if you're looking at the rolled pin near the very bottom of the latch, asking yourself "How the heck does that come out?". Now you (and me too) know!


 8)
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 madmtnmotors

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Re: 1978 CB750 K8 fuel flap query
« Reply #7 on: March 19, 2015, 08:03:17 PM »
And of course, no teaching post is complete without pictures!



Seen better days:




The rolled pin approaching freedom (oh, and a hammer may be required, just be sure to properly support the opposite side):




Once the rolled pin is freed, then the bottom "cone" can be liberated. I used my thumbnail around the base of it to work it free, then the cylinder slides out the top:




There are a total of nine ten parts (there's a little plastic washer under the collar/bezel that rests on the tank lid). I recommend doing this over a large tray while sitting at a table. See the little key "door"? I dropped that on the garage floor and had a heck of a time spotting it. See the little key door spring next to it? Glad I didn't drop that! The outer "cap" is secured by two tabs that are bent over to hold it in place. Be careful not to bend those tabs too far down when reinstalling or they can interfere with the key door. Insert and remove a key after putting the cap on to verify freedom of movement of the key door. The picture below is an "after" shot after I had already treated the cap to a hammer and punch on the anvil:




VIOLA'!




and TA-DA!





I did this this evening after making the previous post. Took all of about 45 minutes, with most of that being painstaking care removing the rolled pin. That is probably the most critical step and the most likely to break something.
« Last Edit: March 19, 2015, 08:17:10 PM by madmtnmotors »
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 Stev-o

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Re: 1978 CB750 K8 fuel flap query
« Reply #8 on: March 19, 2015, 09:07:15 PM »
Nice job, Wlbur.  Do you happen to have a spare lock?
'74 "Big Bang" Honda 750K [836].....'76 Honda 550F.....K3 Park Racer!......and a Bomber!............plus plus plus.........

Offline martin_uk

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Re: 1978 CB750 K8 fuel flap query
« Reply #9 on: March 20, 2015, 02:30:48 AM »
And of course, no teaching post is complete without pictures!





I did this this evening after making the previous post. Took all of about 45 minutes, with most of that being painstaking care removing the rolled pin. That is probably the most critical step and the most likely to break something.

Great job, thanks for sharing, did look to see if pin could be pushed out, but managed to pry mine off from top, but have 2 more without top metal parts.
CB750F1, CB750K8,  Triumph Street Triple R, AJS 350, Triumph 3TA

Offline madmtnmotors

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  • Sunny Central Florida
Re: 1978 CB750 K8 fuel flap query
« Reply #10 on: March 20, 2015, 04:01:17 AM »
Nice job, Wlbur.  Do you happen to have a spare lock?

Wish I did... then I wouldn't have to work so hard to save an abused one!



Great job, thanks for sharing, did look to see if pin could be pushed out, but managed to pry mine off from top, but have 2 more without top metal parts.

After I realized the pin was in a blind bore (one sided) I knew I had to post my results. Opening up the opposite side is pretty easy, the hole stops just below the surface and does not require much effort to expose. You will have to take one apart in order to reinstall the cap since the tabs need to be bent in from the back side.
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 Restoration Fan

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Re: 1978 CB750 K8 fuel flap query
« Reply #11 on: March 20, 2015, 06:31:08 AM »
Hmmm...the lock I purchased as a fuel lock doesn't seem to the be same.  I'm wondering if I have the wrong thing?  (By the way, I went through all my receipts but cannot find where I purchased this)



« Last Edit: March 20, 2015, 06:39:41 AM by Restoration Fan »
Ron

Stella - Logan's Senior Project    78 750K http://forums.sohc4.net/index.php?topic=141761.0

Logan's Reward - CB500 and CB550 Cafes    http://forums.sohc4.net/index.php/topic,147787.0.html

Offline martin_uk

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Re: 1978 CB750 K8 fuel flap query
« Reply #12 on: March 20, 2015, 09:58:23 AM »
Hmmm...the lock I purchased as a fuel lock doesn't seem to the be same.  I'm wondering if I have the wrong thing?  (By the way, I went through all my receipts but cannot find where I purchased this)

Hi Ron, doesnt look correct for K8, which looks like the same as F1.

Thanks for checking, sounds like you have been added to the queue :(
CB750F1, CB750K8,  Triumph Street Triple R, AJS 350, Triumph 3TA

Offline Restoration Fan

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Re: 1978 CB750 K8 fuel flap query
« Reply #13 on: March 20, 2015, 10:01:08 AM »
Hi Ron, doesnt look correct for K8, which looks like the same as F1.

Thanks for checking, sounds like you have been added to the queue :(

LOL, well that would explain why I couldn't figure out how to get it to fit through the hole in the slot :)
Ron

Stella - Logan's Senior Project    78 750K http://forums.sohc4.net/index.php?topic=141761.0

Logan's Reward - CB500 and CB550 Cafes    http://forums.sohc4.net/index.php/topic,147787.0.html

Offline Stev-o

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Re: 1978 CB750 K8 fuel flap query
« Reply #14 on: March 20, 2015, 02:21:45 PM »
Hmmm...the lock I purchased as a fuel lock doesn't seem to the be same.  I'm wondering if I have the wrong thing?  (By the way, I went through all my receipts but cannot find where I purchased this)


Def not the right one.  When you said you bought one, that surprised me as they are NLA.

Let me know if Bill doesnt have one, I may have a spare in the Batcave.
'74 "Big Bang" Honda 750K [836].....'76 Honda 550F.....K3 Park Racer!......and a Bomber!............plus plus plus.........

Offline madmtnmotors

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Re: 1978 CB750 K8 fuel flap query
« Reply #15 on: March 20, 2015, 02:31:59 PM »
Hi Ron, doesnt look correct for K8, which looks like the same as F1.

Thanks for checking, sounds like you have been added to the queue :(

LOL, well that would explain why I couldn't figure out how to get it to fit through the hole in the slot :)

If you have the old one, and it is complete (but just buggered up), then I know a guy that can refurbish them...  ;)  ;D


If they're not buggered too badly!  :o
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 Stev-o

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Re: 1978 CB750 K8 fuel flap query
« Reply #16 on: March 20, 2015, 02:35:20 PM »
Hi Ron, doesnt look correct for K8, which looks like the same as F1.

Thanks for checking, sounds like you have been added to the queue :(

LOL, well that would explain why I couldn't figure out how to get it to fit through the hole in the slot :)

If you have the old one, and it is complete (but just buggered up), then I know a guy that can refurbish them...  ;)  ;D



Sounds like a new business venture!
'74 "Big Bang" Honda 750K [836].....'76 Honda 550F.....K3 Park Racer!......and a Bomber!............plus plus plus.........

Offline Restoration Fan

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Re: 1978 CB750 K8 fuel flap query
« Reply #17 on: March 20, 2015, 05:36:00 PM »
Unfortunately, I have two tanks and both of them came with no tank lock in them. 
Ron

Stella - Logan's Senior Project    78 750K http://forums.sohc4.net/index.php?topic=141761.0

Logan's Reward - CB500 and CB550 Cafes    http://forums.sohc4.net/index.php/topic,147787.0.html

Offline Restoration Fan

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Re: 1978 CB750 K8 fuel flap query
« Reply #18 on: March 22, 2015, 04:18:37 AM »
Martin,
I was looking through the 78/F3 manual today, looking for something else and saw what appears to be the infamous part #23 in another photo diagram.  It looks like maybe that O-ring is intended to go around the little clip that holds the fuel lock into the upper lid?


Ron

Stella - Logan's Senior Project    78 750K http://forums.sohc4.net/index.php?topic=141761.0

Logan's Reward - CB500 and CB550 Cafes    http://forums.sohc4.net/index.php/topic,147787.0.html

Offline martin_uk

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Re: 1978 CB750 K8 fuel flap query
« Reply #19 on: March 22, 2015, 05:09:14 AM »
Martin,
I was looking through the 78/F3 manual today, looking for something else and saw what appears to be the infamous part #23 in another photo diagram.  It looks like maybe that O-ring is intended to go around the little clip that holds the fuel lock into the upper lid?



Great detective work, sounds quite likely.

I have also noticed a thin washer on one of the locks I have, so could be used to take up clearance when lock used without washer?
CB750F1, CB750K8,  Triumph Street Triple R, AJS 350, Triumph 3TA