Honda-SOHC

SOHC.co.uk Forums => CB750 => Topic started by: Grewth on June 14, 2025, 12:45:17 PM

Title: Air filter box gasket
Post by: Grewth on June 14, 2025, 12:45:17 PM
I've just stripped down the air filter box on my F1.
I can see that Honda didn't spare any expense when they designed it.
The rubber gasket joining the three pieces together has degenerated into a nasty sticky mess.
I found a new one (I think) on ebay only £50 with the shipping
I'm just wondering if anyone has managed to substitute anything else for the gasket  ?
I'm thinking that a careful application of black silicone sealant (ie from a builders merchant rather than an auto factor), might do the trick at a fraction of the cost.
Any other suggestions welcome![attachimg=1]
Title: Re: Air filter box gasket
Post by: Martin6 on June 14, 2025, 02:12:11 PM
Personally, I wouldn't silicone it, as that would be a bit of a job for the next filter change. Here's
one for £33.:-
 https://www.ebay.co.uk/itm/365195286710

Also, try the part no. In the David Silver search tool on their website?

Failing that, I'd be thinking door draught excluder, those little rubbery strips that stick to the door frame. Might find one the right dimension.
Title: Re: Air filter box gasket
Post by: Grewth on June 14, 2025, 06:25:13 PM
Actually,  that's the same one that I found.
£16 postage from Germany to be added to that.
This is starting to turn into an expensive game
Title: Re: Air filter box gasket
Post by: Bryanj on June 14, 2025, 09:16:06 PM
It always was expensive game
Title: Re: Air filter box gasket
Post by: SteveW on June 14, 2025, 09:17:11 PM
Not tried it myself but look up Butyl tape.
The stuff they use to stick the plastic moisture barriers behind car door panels.
Might work.
Title: Re: Air filter box gasket
Post by: McCabe-Thiele (Ted) on June 15, 2025, 08:34:53 AM
If you search on e bay for sponge gasket strips there are quite a few that look like they might be suitable.
This is one I found comes in various profiles that you could use.
In the past I have use Hylomar Gasket Maker on car parts.

 www.ebay.co.uk/sch/i.html?_nkw=sponge+gasket+strips&_sacat=0&_from=R40&_trksid=p3519243.m570.l1313

www.ebay.co.uk/itm/226338105498?_skw=sponge+gasket+strips&itmmeta=01JXS7QJTHXDFN8YK802Q9SH67&hash=item34b2cd689a%3Ag%3AfnQAAOSwZ-RkjXiC&itmprp=enc%3AAQAKAAAA0FkggFvd1GGDu0w3yXCmi1fFLiDLb2SBvaDUm811JDm0gyRmBTlaT9x77ME4nBMoKEtCnyL5UHsryCxMHQP5FjY74%2B0JixQPVUcYvnj7uMe75FJDxNfcrHwiPa1Hun9%2BNjgrUlAw40M64ytnAge9qV1kx8mAXxovDlDU0zwSvseG6NPholqV2gyfdfSkct%2FOUagWsWzWetMSrexeiKfwS2ulcJ1DAqyrRBvGbP3C3ai%2BlFfErG6bdyia0LEdcIVQhm1S%2B2ksN4a0juOfm4b%2FqV8%3D%7Ctkp%3ABk9SR7at3qfuZQ&var=525530042411
Title: Re: Air filter box gasket
Post by: Grewth on June 15, 2025, 10:31:02 AM
If you search on e bay for sponge gasket strips there are quite a few that look like they might be suitable.
This is one I found comes in various profiles that you could use.
In the past I have use Hylomar Gasket Maker on car parts.

 www.ebay.co.uk/sch/i.html?_nkw=sponge+gasket+strips&_sacat=0&_from=R40&_trksid=p3519243.m570.l1313

www.ebay.co.uk/itm/226338105498?_skw=sponge+gasket+strips&itmmeta=01JXS7QJTHXDFN8YK802Q9SH67&hash=item34b2cd689a%3Ag%3AfnQAAOSwZ-RkjXiC&itmprp=enc%3AAQAKAAAA0FkggFvd1GGDu0w3yXCmi1fFLiDLb2SBvaDUm811JDm0gyRmBTlaT9x77ME4nBMoKEtCnyL5UHsryCxMHQP5FjY74%2B0JixQPVUcYvnj7uMe75FJDxNfcrHwiPa1Hun9%2BNjgrUlAw40M64ytnAge9qV1kx8mAXxovDlDU0zwSvseG6NPholqV2gyfdfSkct%2FOUagWsWzWetMSrexeiKfwS2ulcJ1DAqyrRBvGbP3C3ai%2BlFfErG6bdyia0LEdcIVQhm1S%2B2ksN4a0juOfm4b%2FqV8%3D%7Ctkp%3ABk9SR7at3qfuZQ&var=525530042411

Thanks for that.
Well you've just given me a solution for the damaged seal on the under seat tool box anyway.
And £2 a metre is the sort of price that my wallet likes.
Looks like it would be quite easy to cut this stuff and join it with contact adhesive to fit a complex shape
Title: Re: Air filter box gasket
Post by: Oddjob on June 15, 2025, 03:05:52 PM
Why not try using some of this stuff, proper ORing gasket material, most likely the same as Honda used, square section, so it should sit right. Just order a couple of metres and experiment. Fairly sure other models use the same type of stuff, wasn't there the same type of stuff around the black bomber air filter housing?

https://www.polymax.co.uk/rubber-cords/nbr-square-section-cord/nbr-square-rubber-cord
Title: Re: Air filter box gasket
Post by: Grewth on June 15, 2025, 04:04:29 PM
Why not try using some of this stuff, proper ORing gasket material, most likely the same as Honda used, square section, so it should sit right. Just order a couple of metres and experiment. Fairly sure other models use the same type of stuff, wasn't there the same type of stuff around the black bomber air filter housing?

https://www.polymax.co.uk/rubber-cords/nbr-square-section-cord/nbr-square-rubber-cord

Many thanks  !
Once again the price of the stuff is much to my liking.
I think I might just buy a bit of everything and start to experiment
Title: Re: Air filter box gasket
Post by: Oddjob on June 15, 2025, 07:26:52 PM
If you find one that works fine then you can let others know what worked, what size to order or even make a few and sell them yourself. I’d use some gel type glue to bond the stuff in place and probably some super glue to join the ends so it’s got no joint to leak past.