Air Filter box woes

[chasingmytail]

Hey all, I've been lurking around the forum for a couple months now, figured I'd introduce myself and Lucille.


Now to my question about the airbox...

I have a fairly clean 78 cb750k here... In the middle of a tapered bearing conversion/fork seals/progressive springs overhaul and getting everything ready for the parts to arrive I decided I'd check the condition of the airfilter and had a helluva time getting the lower portion of the box off. These pics will show you why.  
The top portion of the airbox... Notice the print on the box? Is this thing from a supersport?
 
The lower portion of the airbox, bottom side. Notice the sunlight coming through? The carving around the bolts?

Close up of the bottom.

Wondering if this explains some of the Air/fuel issues... Though the holes are awfully small to be causing anything dramatic... right?

What do you all think?

[Piute]

   Those are the same #'s N letters as mine,i noticed mine was cracked when 1st took off and used some fiberglass res. to glue it (hand 80 grt./clean)I've always put mine in as 1 unit (top/filter/bottom).
  As touchy as it seems these are MayBe(bigg hole)

[TOOLS1]

Welcome to the forum. All the later box's have 750 F on them. You do need a new bottom though. Also they are a little tight to get on, and off. Your air/fuel problem are the keyhole carbs. They are prone to the pilot jets plugging up.
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[chasingmytail]

I was hoping you two would chime in!

Any tips on hunting one of those bottoms down? It looks as though the bolts from the bottom (the long cylindrical type) were too short, hence the PO carving into the box and making due... Weird.

Any quick way to unclog that pilot? The carbs were allegedly just redone a little under two thousand miles ago(PO)...

At any rate, thanks for the quick response fellas. Can't tell you how much I've learned from you guys digging around on this site!

[shinyribs]

I have 3 airboxes. One off a '76F,another off a '78K and another I'm not sure about. I'll try and get some pics up and see if one of them matches yours.I want be using any of them.

[shinyribs]

Oh yeah....sweet ride! "Fairly clean" is an understatement!

[chasingmytail]

Lucille is blushing. She says thanks

I'll be waiting for those pics! You'd certainly be saving a whole heap of trouble.

I've been drooling over the ride you have posted, the silver 78k, I think. Wish I had the space you have!

[shinyribs]

My brain kicked in and I remembered you posting about your air box woes. Yours looks similar to mine,but honestly I cant say for sure. I do see your holes,but they do not seem severe to me. They will leak past the filter,possibly letting junk or whatever into the engine/carbs,but they dont seem to me to be big enough to cause serious tuning issues.It would be a good idea to get that sealed up,but your tuning issues are likely unrelated.JMO,of course.

[chasingmytail]

I'm willing to bet your correct, but it seems like a weak link that needs fixing anyway. You still didn't give me a price! Worse comes to worse I can resell it.

[Re-run]

Nice bike, wish mine were that clean! Maybe someday...
Anyways, Those holes in the bottom will not be enough to seriously throw anything off. They were caused by 1 of 2 things though. Some dumbass tightening the bolts WAY too much or by a person who cross threaded the bolts and kept trying to tighten.
See these bottoms are not meant to turn, the plastic holds them so you do not need a second wrench. People end up stripping them cause they think they need to be super tight and that isn't the case.
I ALWAYS split my airbox when I take it out. It is so much easier than as 1 unit. I used to do that so, I know.
Use a resin of some sort to fill the holes and hold the bolts and you should be fine there.

What sort of fuel issues are you having? I assume this isn't your first bike so we would need to know what your other bike was for comparison purposes.

[2slow4u]

Hey SOHC riders! I sent a set of OEM carbs from my 1978 Honda SS750 to Mike Nixon including shipping time about 2 weeks I had my carbs back installed them bike runs great! The cost was $412.00 add my shipping cost to Mike $430.00 I can't tell you how pleased I am. I'd sent then to a guy in Hazleton WI. no service bike wouldn't run it may have been my fault I may of had the fuel line hooked to the wrong nipple. IDK if the Hazleton WI guy would have listened to me not blown me off it would have saved me time & lots of money. Need carb work see Mike at just carbs in AZ.

[TOOLS1]

I had a guy call me the other day about a running problem on an old 305 Super Hawk the other day (he had been referred to me by the President of the Local VJMC.) He told me the names of several people he had spoken to about this, including Mike Nixon. I told him what the problem was, incorrect O-ring on the air screw, and he said that I was the only person he spoke with that had said that was the problem. He said that was the only new idea and everything else had been done/redone. I charge $35.00 a carb to rebuild a single carb, so that makes it $140.00 plus parts to rebuild a set of 4 carbs. I would be happy to rebuild a set of carbs mail order. However I prefer to install the carbs and get the bike running myself. That way I can sync and adjust, or rejet accordingly.
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