Carb to airbox fitting

Ran into a new problem today, I got the carb slipped into the head boots, then discovered I couldn't get the airbox to slide on the back side. As near as I can tell the diameter of the intakes are 54mm but the airbox only seems to have about 51mm openings in the boots. Is it possible the boots could have shrunk after many years of sitting around? I'm not sure if the airbox boots are supposed to be rubber, but they feel more like a flexible plastic.

I ended up pulled the carb and airbox off the bike to check measurements. The only thing I can think of at this point is to make up a taper and use the heat gun to open up the boots a little more. The good news is that the rubber boots on the head have more flexibility than I initially thought, and working them from putting the carb on the first time seemed to make them a lot more flexible.

Considering the stiffness of the airbox boots, I'm not really sure how that spring is supposed to hold them in place? Seems like I should just throw some hose clamps on there to keep everything solid. Has anyone else done that?

Oh sorry... this is a 1981 KZ1000J.

The ducts become hard over time. They should be very flexible & pliable. Get a new set.
From the diagrams at Partzilla the 1000J ducts are still available at the dealer.
Z1Enteprises.com probably has them (oem).

I had similar troubles when trying to refit the air box rubbers on my kz900 as they had hardened a little and with your hand down inside the airbox like a gynacologist you really need these to slip on easily.
I first tried leaving them in just off boiling water for a minute which made them very soft and pliable but by the time I had dried them off and got them in place they were soon hardening up again.
I found the best result from getting them in the air box and then carefully blowing a hairdrier over the ends and in the airbox until supple then they simply slipped on with no trouble. Saved me £75 for a new set.

Part # 14073-1048 DUCT, AIR FILTER - $11.22 each

www.partzilla.com/parts/detail/kawasaki/KP-14073-1048.html

Forcing the parts together using heat and what have you may work for a while, but long term you are better off just getting new parts.

Yeah I dug up the partzilla listing last night, with shipping it comes out to just under $53. Unfortunately I got slammed with an unexpected $500 bill this week (god I hate having to pay for parking at my office), so I probably won't be buying any new parts this month. I had previously read some other discussions about problems with airflow when the rubber gets hard, so I'll just go ahead and get new ones when I can. In the meantime, lots of work left to prep the tank for painting and getting the wiring harness back in place, so the time won't be wasted.

Anyway thanks for the confirmation on what I *should* be seeing here. The way they feel, I really thought those ducts were plastic!

I just purchased a set for my J3 from my local Kawasaki dealer. $16.00 ea. Canadian

If the parts prices in the U.K. were the same as the other side of the pond then opting for new parts every time wouldnt be an issue.
The availability and pricing unfortunately is very different.
What is $44 for a set on the partzilla site is £75 in the U.K. around $97

@zak900 -- yeah I've noticed that on a lot of things. Really sucks for you you guys. Might be worth checking ebay though, I see a lot of folks like Partzilla selling there, maybe they have decent shipping rates? Too bad you still have to pay VAT though.

Shdwdrgn wrote: @zak900 -- yeah I've noticed that on a lot of things. Really sucks for you you guys. Might be worth checking ebay though, I see a lot of folks like Partzilla selling there, maybe they have decent shipping rates? Too bad you still have to pay VAT though.

Unfortunately most shipping prices add so much to make it not wothwhile. Ive often seen small cheaper parts on ebay where the shipping is two or three times the cost of the part.
Might be a business opening there for some of you guys forwarding parts.