Author Topic: OOps, always worrying!  (Read 4201 times)

Offline Otis

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OOps, always worrying!
« on: August 20, 2026, 12:08:09 PM »
In the recent thread about main fuse blowing I explained that after finding the broken wire I had to dismantle the air filter housing for access.

I was meticulous in photographing the components before hand and put everything in the air filter housing for safe keeping. Upon reassembly I now have a bolt without a home. I have spent half an hour looking to see where it might go but to no avail. Would anybody have any idea where this little bot and washer should be because for the life of me I can't see it.

Thank you
Graham

1972 Honda CB350F
1997 Ducati ST2

Offline McCabe-Thiele (Ted)

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Re: OOps, always worrying!
« Reply #1 on: August 20, 2026, 12:44:40 PM »
Is it the one inside the filter housing right at the bottom?
Honda CB400NA Superdream (current money puddle)
Honda CB500 K1 (second money pit)
https://www.sohc.co.uk/index.php/topic,28541.0.html
Honda CB400 four super sport (first money pit)
Link to my full restoration http://www.sohc.co.uk/index.php/topic,23291.0.html
This is a neat 500 restoration in the USA.
http://forums.sohc4.net/index.php/topic,151576.msg1731556.html#msg1731556

Offline Otis

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Re: OOps, always worrying!
« Reply #2 on: August 20, 2026, 12:51:40 PM »
Is it the one inside the filter housing right at the bottom?

OMG, thank you so much, I've been worried sick about it
Graham

1972 Honda CB350F
1997 Ducati ST2

Offline Otis

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Re: OOps, always worrying!
« Reply #3 on: August 20, 2026, 02:07:30 PM »
Is it the one inside the filter housing right at the bottom?

Notwithstanding my initial excitement I'm not sure that is correct. There is a hole at the bottom but smaller diameter plus there is a 4 inch void beneath so not sure what any bolt would achieve. Hmmm!
Graham

1972 Honda CB350F
1997 Ducati ST2

Offline Otis

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Re: OOps, always worrying!
« Reply #4 on: August 20, 2026, 03:19:48 PM »
For some unknown reason I am getting a message saying that I am not allowed to access these photos. 1st one OK but next two no good
Graham

1972 Honda CB350F
1997 Ducati ST2

Offline Athame57

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Re: OOps, always worrying!
« Reply #5 on: August 20, 2026, 03:24:38 PM »
Have you thought of looking at an exploded diagram of the area? Such an image you'll get on the CMSL site.
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1978 CB400F2 named Elen.

Offline Athame57

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Re: OOps, always worrying!
« Reply #6 on: August 20, 2026, 03:30:52 PM »
Looking at the size of that washer, could it be one of those bolts that have a rubber cushion beneath, and do you remember how many of those you fitted back?
« Last Edit: August 20, 2026, 03:38:03 PM by Athame57 »
I brake for animals!
1978 CB400F2 named Elen.

Offline McCabe-Thiele (Ted)

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Re: OOps, always worrying!
« Reply #7 on: August 20, 2026, 03:57:54 PM »
Is it the one inside the filter housing right at the bottom?

Notwithstanding my initial excitement I'm not sure that is correct. There is a hole at the bottom but smaller diameter plus there is a 4 inch void beneath so not sure what any bolt would achieve. Hmmm!

I might be confusing it with the 500.
There are similar bolts & washers in the steel frame for the battery box. Did you remove one of those perhaps?
« Last Edit: August 20, 2026, 03:59:27 PM by McCabe-Thiele (Ted) »
Honda CB400NA Superdream (current money puddle)
Honda CB500 K1 (second money pit)
https://www.sohc.co.uk/index.php/topic,28541.0.html
Honda CB400 four super sport (first money pit)
Link to my full restoration http://www.sohc.co.uk/index.php/topic,23291.0.html
This is a neat 500 restoration in the USA.
http://forums.sohc4.net/index.php/topic,151576.msg1731556.html#msg1731556

Online exvalvesetdabbler

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Re: OOps, always worrying!
« Reply #8 on: August 20, 2026, 05:17:08 PM »
There's two like that that holds the voltage regulator to the battery box

Offline Otis

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Re: OOps, always worrying!
« Reply #9 on: August 20, 2026, 05:29:24 PM »
Looking at the size of that washer, could it be one of those bolts that have a rubber cushion beneath, and do you remember how many of those you fitted back?

That's a really useful diagram and thanks for sharing. I can confirm that all appears to be present and correct so I guess I will just have to wait and see if something goes array at some stage. It's a small bolt so I guess nothing structural.
Graham

1972 Honda CB350F
1997 Ducati ST2

Offline Otis

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Re: OOps, always worrying!
« Reply #10 on: August 20, 2026, 05:30:12 PM »
There's two like that that holds the voltage regulator to the battery box

I will double check that because I did remove the regulator; thanks
Graham

1972 Honda CB350F
1997 Ducati ST2

Online exvalvesetdabbler

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Re: OOps, always worrying!
« Reply #11 on: August 20, 2026, 05:32:52 PM »
The hole in the bottom of the air filter housing is for a self tapping Phillips screw that holds the plastic oil separator from the  crankcase breather.

The only other mounting for the battery box is under the battery but that is a captive bolt on  the engine mounting bracket so only takes a nut and washer.

It's got me stumped.

Regards
Dave

Offline Athame57

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Re: OOps, always worrying!
« Reply #12 on: August 20, 2026, 05:40:15 PM »
Are you sure this bolt didn't come out of your pocket at some point, that would be me all over!  ;D
I brake for animals!
1978 CB400F2 named Elen.

Offline McCabe-Thiele (Ted)

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Re: OOps, always worrying!
« Reply #13 on: August 20, 2026, 05:57:53 PM »


The only other mounting for the battery box is under the battery but that is a captive bolt on  the engine mounting bracket so only takes a nut and washer.


Regards
Dave

Could that captive bolt have been changed to a nut & bolt for ease of removal in the past?

Do you have a spare nut as well?
Honda CB400NA Superdream (current money puddle)
Honda CB500 K1 (second money pit)
https://www.sohc.co.uk/index.php/topic,28541.0.html
Honda CB400 four super sport (first money pit)
Link to my full restoration http://www.sohc.co.uk/index.php/topic,23291.0.html
This is a neat 500 restoration in the USA.
http://forums.sohc4.net/index.php/topic,151576.msg1731556.html#msg1731556

Offline Otis

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Re: OOps, always worrying!
« Reply #14 on: August 20, 2026, 06:13:34 PM »
I can't believe how much of your kind and helpful time I have taken from you very generous gentlemen.

These forums are just fantastic and so often it is the simplest of tips and ideas that produce results. You have all been incredibly helpful but this will perhaps have to remain a mystery for the time being. I would love to admit that this bolt was just lurking in my pocket but sadly not. It also doesn't have an associated nut. The regulator is only held with a single nut but remains robust in its position.

When something drops off or fails I promise to eat humble pie and advise you of my findings.

Thank you all.
Graham

1972 Honda CB350F
1997 Ducati ST2