Topic: NEWBIE - '76 CB75F Airbox

[Superfly44]

Stumped - it seems the top bolt and bottom hex-head are attached, and the bottom is only "locked" with the blasting molded hex.  I am trying to simply take the airbox apart, but loosening the top only turns and strips the bottom "bolt" in the hex mold, and I can't get anything on it to stop it from turning.  I see the simple explanation of "remove the wing nut", but this is not the case as it's only held in the plastic molded hex..... make sense?

any suggestions?

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[Jerry Rxman Griffin aka MuthaF'er]

I have been known to jam a flat blade screwdriver into the turning bottom. Or you can cut out around the nut to insert a socket

[seanbarney41]

Yup 75 750f was the first model to not have the good old wing nut.  When those nuts start rotating in the hex, it is a real pita.  Jerry has suggestions that worked for me.  Then get on ebay and buy the earlier airbox with the wing nuts...it will swap right on.

[goodtryer]

I had a similar situation with my 78 750k. The lower nuts were missing form the air box when I got the bike. I bought some coupling nuts, hex head bolts and some fender washers to make my own replacements.

It has worked out really well and only cost a few bucks. Easy to see and reach with a wrench.

The first pic is the packing list of parts I bought. The ones I used are line item #1. Line item #2 didn’t fit as well as the others. The last pic shows the coupling nuts fitting in the air box lower.

Once I figured out the right depth to place the coupling nut on the bolt so that the air box was sealed (but not too tight) I used a small amount of threadlocker on the new bolt to keep it set.
 
I would definitely do it again if faced with the same situation.

Cheers

[scottly]

Someone here once suggested heating up an appropriate size socket, and pressing it into the plastic until it would engage the hex? 

[Superfly44]

Thanks All.... great points and suggestions.
Tomorrow afternoon I'll share the "solve" and results!
Wish me luck.

[Don R]

Someone here once suggested heating up an appropriate size socket, and pressing it into the plastic until it would engage the hex? 

 I have done this, it does minimum damage and works. I used a hot air gun to heat the socket so it's not ruined either.

[HondaMan]

I filled in some of the damaged nicks and bruises with JB Weld on one many years ago, it's still working fine, too.

[Superfly44]

All great suggestions.
I used all of them.
1) used a 2 size up socket (12mm)
2) scribed an outline
3) pried the screwdriver in to create space
4) knifed a gouge around the hex nut (careful to not go too deep) out to the scribe
5) used a heart gun top heat both the box plastic and sockets until i could get bit on the hex head
6) looks a bit rough, but hidden with the washer used from the packing list @goodtryer sent

Thanks all.... and best of luck.

[johans]

 ++   goodtryer   , did the same fix . Mark the bolt(s) with a red paint marker to remind you in the future .