Topic: Looking for Airbox Assembly for 78 cb550k

[mkmob]

Hi folks,

This is my first post on these forums. I recently purchased a 1978 cb550k and i'm in the process of restoring it. This is also my first bike and I'm completely new to the art of motorcycle repair/maintenance. But it's something I've wanted to do pretty much my whole life and I've already learned a lot.

Anyway, to the point... The person I bought the bike from replaced the original airbox assembly with pod filters and either sold or lost it. So now I'm trying to track down a replacement and I'm having some trouble finding one. I know that the 77 and 78 550's have different carbs than the other 4's and so I've been searching online for the assemblies from those. There's very few original airboxes online for any of the 550's and I have yet to find one for either a 77 or 78.

Anyone have any suggestions on where I might be able to find one of these?

Thanks!

[flybox1]

Welcome.  Use a site like CMSNL.com and their parts fiche to locate the part(s) number(s). 
In your case, you'll need most of the parts listed.   

https://www.cmsnl.com/honda-cb550k-1978-usa_model7222/partslist/F++16.html#.XC1AatTwYdV

[flybox1]

how 'bout this...
https://www.ebay.com/itm/77-78-Honda-CB-550-F-K-Four-Supersport-used-Airbox-Filter-Housing-17313-390-780/132803063291?hash=item1eebadedfb:g:UDkAAOSwksBbYY5w

[bryanj]

That is the hardest part to find, or rather the rubbers between box and carbs are.

[Scott S]

 The air box itself is the same on all 550's. The rubber intake boots are different for '77-78 and new replacements are available.

[AlekStooge]

I have a 1978 air box that I won't be using.

[bryanj]

Scott, i regularly see the rubbers for the 500/550 with none PD carbs but i cannot find any for the 77/78K WITH PD carbs as they are different. Airbox is a different part number as well.

[Scott S]

 For the rubbers, email Paul at Classic Motorcycle Solutions.

  mybluebike2004@yahoo.com

 The plenum for the air box is the same. It just uses different intake rubbers. The air filter section only changed as far as EPA stuff; where breather hoses went, crankcase recovery system,  etc. Any 500/550 air box will work if you're not concerned about the exact vapor recovery system for your particular year.

[Deltarider]

The CB550K3/4 had somewhat longer intake runners as these models were marketed for cruising and less for sportive riding.

[Scott S]

 They used shorter rubbers on the intake manifolds and longer rubbers on the plenum, to fit the PD series carbs and use the same manifolds and air box parts.

[TwoTired]

They used shorter rubbers on the intake manifolds and longer rubbers on the plenum, to fit the PD series carbs and use the same manifolds and air box parts.

+1   
...Except the intake manifolds were different than the early models with elimination of the vacuum test ports, as the PD carbs have them incorporated into the carb bodies.

The rubber bits were different because of mechanical size fitment of the PD carbs.  Absolutely nothing to do with the Delta's fictional storytelling.

[mkmob]

Wow, I didn't expect this many replies so quickly! Thanks everyone for all the helpful information! I was starting to feel a little discouraged but I think I'm now pointed in the right direction.

Good to know that the air boxes are essentially the same aside from the boots. I'm now wondering if the the previous owner attempted to rejet the carbs when they installed the pod filters. Although it seems from what I read, retuning it with the original air box should be relatively straightforward.

Anyway, I'm glad to see that this community is still so active and helpful. Hopefully I'll be able to pay it forward once I get some more experience under my belt.

[Deltarider]

In reply #8 I passed on the info briefed by Honda back then. These models were marketed in continental Europe as cruisers opposed to the somewhat sportier F models. Honda also explained that that's why the K3 had a rear sprocket of 34 teeth fitted and not the 37 teeth sprocket the sportier F models had. If that's fictional storytelling, at least I did it in conjuction with Honda.

[05c50]

Wow, I didn't expect this many replies so quickly! Thanks everyone for all the helpful information! I was starting to feel a little discouraged but I think I'm now pointed in the right direction.
Anyway, I'm glad to see that this community is still so active and helpful.

"still active" haha, it's a full time job trying to keep up with all the daily posts.

.........Paul

[754]

I have one, less the rubber boots in 4 sale.  In the last 2 or 3 weeks.
 Take a look, I be back on here in a few hours.

[trigger]

Scott, i regularly see the rubbers for the 500/550 with none PD carbs but i cannot find any for the 77/78K WITH PD carbs as they are different. Airbox is a different part number as well.

These are the ones for the PD carbs Bryan >>> https://www.ebay.co.uk/itm/77-78-HONDA-CB550K-K3-CARB-INTAKE-SET-INSULATOR-4-INTAKES-INCLUDE-CI-CB550K3INBT/251544929658?hash=item3a913f057a:g:xVYAAOxyF0pTiW5r:rk:3:pf:0

[TwoTired]

In reply #8 I passed on the info briefed by Honda back then. These models were marketed in continental Europe as cruisers opposed to the somewhat sportier F models. Honda also explained that that's why the K3 had a rear sprocket of 34 teeth fitted and not the 37 teeth sprocket the sportier F models had. If that's fictional storytelling, at least I did it in conjuction with Honda.

My K3 had/has a 37 tooth rear sprocket  In fact, all my CB550 do, along with the same size front sprocket.  Please show the part number difference between the F model and the K model to back up your story.
The CB500s here in the US had 34 tooth rear sprockets.  They also had different primary chain gearing to offset the final ratio gearing.

[Deltarider]

In reply #8 I passed on the info briefed by Honda back then. These models were marketed in continental Europe as cruisers opposed to the somewhat sportier F models. Honda also explained that that's why the K3 had a rear sprocket of 34 teeth fitted and not the 37 teeth sprocket the sportier F models had. If that's fictional storytelling, at least I did it in conjuction with Honda.

My K3 had/has a 37 tooth rear sprocket  In fact, all my CB550 do, along with the same size front sprocket.  Please show the part number difference between the F model and the K model to back up your story.
The CB500s here in the US had 34 tooth rear sprockets.  They also had different primary chain gearing to offset the final ratio gearing.

It's on p.62 of the appropiate Parts List which you can study here: http://www.honda4fun.com/pdf_parts_list/pdf_spac500-550/CB500-550_K3-K4.pdf At your service.

[Tracksnblades1]

Good info, possibly can clear up any little anecdotals.
Thanks for the Part numbers Delta, sometime them pesty specifics can be hard to produce.

Good Health and a prosperous 2019

[TwoTired]

In reply #8 I passed on the info briefed by Honda back then. These models were marketed in continental Europe as cruisers opposed to the somewhat sportier F models. Honda also explained that that's why the K3 had a rear sprocket of 34 teeth fitted and not the 37 teeth sprocket the sportier F models had. If that's fictional storytelling, at least I did it in conjuction with Honda.

My K3 had/has a 37 tooth rear sprocket  In fact, all my CB550 do, along with the same size front sprocket.  Please show the part number difference between the F model and the K model to back up your story.
The CB500s here in the US had 34 tooth rear sprockets.  They also had different primary chain gearing to offset the final ratio gearing.

It's on p.62 of the appropiate Parts List which you can study here: http://www.honda4fun.com/pdf_parts_list/pdf_spac500-550/CB500-550_K3-K4.pdf At your service.

All of which has nothing to do with intake runner/rubber differences.  But something to do with euro and US marketing differences.
Or, are you now saying the intake rubbers are different for US and euro markets, too?

[Deltarider]

I've been quite specific in reply #12, sir. Now, this may have been spinned by Honda but that's how it was brought by them when the K3 was released to the German market. Please see my reply #8 where I specifically used the word 'marketed'.

[b1jackson]

For the rubbers, email Paul at Classic Motorcycle Solutions.

  mybluebike2004@yahoo.com

Exactly what I was looking for.  My boots are cracked and crusty!

[bryanj]

The person who posted the ebay link, those are carb to head rubbers that all Honda dealers can get if they wish to try and help. Its the plenum to carb rubbers that only exist when made by a member on here.

[Tom in Newcastle......Ontario]

https://www.ebay.ca/itm/77-78-Honda-CB550-CB-550-K-Air-Cleaner-Box-Airbox-Intake-Boot-Tube-Snorkel-Set/183501651148?hash=item2ab98cfccc:g:8ocAAOSwNcBahGE1&vxp=mtr

[Scott S]

 I haven't bought any in a while but the ones Paul sells are (were) WAY less expensive.