Author Topic: 500/550 airbox compatibility?  (Read 145 times)

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Offline kerryb

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500/550 airbox compatibility?
« on: November 12, 2024, 08:43:27 PM »
Hi, I did some searching and part numbers don’t match, but the photos look identical for an air box from a 77 cb550k to fit into a 71 cb500.  Even the goofy hardware is the same.  Can anyone confirm or deny it will fit close enough to run well?
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Offline bryanj

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Re: 500/550 airbox compatibility?
« Reply #1 on: November 12, 2024, 09:57:40 PM »
No they wont swop, the 500 does not have the oil mist recirc bits below the filter and the K3 has different carbs so the rubber inlets are different
Semi Geriatric ex-Honda mechanic and MOT tester (UK version of annual inspection). Garage full of "projects" mostly 500/4 from pre 73 (no road tax in UK).

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Offline kerryb

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Re: 500/550 airbox compatibility?
« Reply #2 on: November 13, 2024, 04:51:01 AM »
Thank you, that’s unfortunate.
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Offline bryanj

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Re: 500/550 airbox compatibility?
« Reply #3 on: November 13, 2024, 05:10:24 AM »
BUT all the 500 and the 550K up to and including K2 will fit even with the oil mist seperator which you can just leave out and fit the 500 element with breathers disconnected.
Plus you can get aftermarket carb to airbox rubbers.

Sorry didnt give that info before but had limited connection as on vacation
Semi Geriatric ex-Honda mechanic and MOT tester (UK version of annual inspection). Garage full of "projects" mostly 500/4 from pre 73 (no road tax in UK).

Remember "Its always in the last place you look" COURSE IT IS YOU STOP LOOKIN THEN!

Offline kerryb

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Re: 500/550 airbox compatibility?
« Reply #4 on: November 13, 2024, 05:33:35 AM »
Thank you again, that widens the search quite a bit.
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Offline Gurp

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Re: 500/550 airbox compatibility?
« Reply #5 on: November 13, 2024, 05:35:14 AM »
I've got a box of air box stuff in the garage. I'll try to remember to shoot you some pictures soon

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Offline kerryb

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Re: 500/550 airbox compatibility?
« Reply #6 on: November 13, 2024, 05:58:23 AM »
Ok, but put a ruler across the carb side of the distribution box to see carb spacing.   Maybe we can trade, what are you looking for?
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Offline Little_Phil

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Re: 500/550 airbox compatibility?
« Reply #7 on: November 13, 2024, 11:31:27 AM »
You want to take the bits off the 77/78 K3 in the pic and use them on the 500? I think the box for the filter will be ok. You don't need the oil mist collection bits in the bottom and can be discarded as the 500 vented to air. The forward box is also probably ok as I think the difference in spacing of the carbs is taken care of by the rubbers connecting this to the carbs. But you will need a new air filter and the 8 new rubber connectors that go both ends of the carbs.