Cafe Racer Forum banner

1 - 15 of 15 Posts

·
Registered
Joined
·
119 Posts
Discussion Starter #1 (Edited)
Restoring rubber airbox ducts?

I'm looking to make the old, dried out intake boots (actually air cleaner ducts)a little less rock hard. Read on the SOHC4 forum that people are getting good results from a soak in 30% wintergreen oil, 70% Xylene.

Anyone try that and get results?

What else could I do to make the rubber pliable without heating it to almost melting?

Thanks.
 

·
Registered
Joined
·
2,087 Posts
search the rd400 thread - something like what to do with rd400 - its pretty amazing restoration level stuff and if I recall right rubber was covered in the discussion. Was it dean's bike? I am bad with names.
 

·
Registered
Joined
·
1,126 Posts
Heikki .. I think you are right about me posting a rubber restoration thread somewhere ( well, more of test actually ) . I just searched the site and can not find it (??)

So here is what I thought I posted some time back.... Intake boots are not "rubber" , they are made from a fuel safe pliable "rubber like" (poly) compound using (and/or) nitrile or fluorosilicone or urethane in combination with who knows what. So not really knowing for sure what you are trying to "restore" is a flaw in any garage tests...

The nos 40 year old boots I have seen/ used, are good, so it's not the time that degrades them like actual rubber , it is the cycle of ambient conditions, cylinder head heat , fuel, chemicals etc that age them . ( my theory anyway)

If boots are cracked .. or crumbly, they are doa .. just throw them away.

If they are less that pliable, yet not cracked or otherwise degrading- PB Blaster does soften them without "eating them" long term effects are unknown. The nasty stuff I use on plastic, the vintage can of color back works on intake boots

note on plastics:
I use a can of what I assume is a banned toxic chemical today. I have had the same can for 30+ years and still use it ! It's what turtle called color back, vinyl and plastic restorer ( they make another version today for oxidized paint- not the same stuff ) When I run out of the stuff I have, I will buy some Autoglym that UKTony uses ( where has Tony been? .. business must be good or maybe Jules is more interesting that us ! )
 

·
Registered
Joined
·
119 Posts
Discussion Starter #8
Kero, I searched my ass off but only found Tony's method of making things shiny again.

Just to be clear, I'm talking the intake boots for the carbs coming from the airbox. I think they're called air cleaner ducts or something.


Dean, pure gold on the PB blaster idea. I'll try it out before spending the money on these:
Airbox Hoses (4) KZ550 KZ650 | 11015-057-K | www.z1enterprises.com
Pricing out the xylene and wintergreen oil, ^^ is only slightly more.

TCed, I geeked out hardcore on that article. Many thanks.
 

·
Registered
Joined
·
23,303 Posts
I have used wintergreen oil and water. It works but it isn't permanent. You'll have to do it again the next time you remove them.
 

·
Registered
Joined
·
3,459 Posts
In my experience, early 80's Kawasaki and Suzuki use different materials for intake parts compared to most Yamaha and all Honda
Xylene alone doesn't work (tried it)
Except for the cost, the best thing to do would get new ones from Kawasaki (in all probability they still have them)
I've tried most things to soften up intake boots/air box connectors over the years, sometimes just boiling parts in water with a little detergent may work as some of the chemicals absorbed into the pieces may 'come out' and change structure (followed by spray down with WD40)
Suzuki air box to carb connectors just get glass hard, anything that will soften them generally will dissolve them, it got to the point where we (the shop) wouldn't take on carb re-build/cleaning on 5 yr old Suzuki's unless customer was also willing to buy new airbox to carb boots
 

·
Registered
Joined
·
31 Posts
I've tried most things to soften up intake boots/air box connectors over the years, sometimes just boiling parts in water with a little detergent may work as some of the chemicals absorbed into the pieces may 'come out' and change structure
this
I've done this to get one more use out of otherwise petrified airbox to carb boots. Just drop them in boiling water until they are pliable again, doesn't take long, maybe a minute. You can keep the hot water in a large pyrex measuring cup at the workbench to cut down on travel time. The boots will come out nicely pliable and you should be able to get them stretched out and installed before they cool down again. I've used a pipe spreader on them while hot to get a more permanent result but they will get petrified again. Work fast, don't scald yourself.
At some point you're gonna need new ones.

Mark
 

·
Registered
Joined
·
6,586 Posts
I've used a heat gun on XJ carb boots with good success. Put the carbs and airbox on, then heat each individual boot and squish it into place. Welding gloves are handy here.
 

·
Registered
Joined
·
658 Posts
303 aerospace protectant.
Amazon.com: 303 aerospace protectant


In what ever size container you want. If you have an Outdoor Store around (like REI) you can find it there. I have soaked old stiff ropes in the stuff and they have become pliant and useable again. It acts as sunscrene for plastics without damaging the material it means to protect. You can even drink the stuff, it's that mild.
 

·
Registered
Joined
·
2,740 Posts
Most likely if your intake rubbers are harden they will have air leak cracks in them - I'd recommend just replacing them. If your trying to recondition the rubbers on the intake side of the carbs (between the airbox and carb, I've had good luck with soaking them in armor all to soften them up a little. You can use a small coffee can with a cover, put the rubber items in the can and spray the crap out of them. Close the lid and shake them up a little and leave it covered for a day or so. Pull the rubber items out and wipe them down before putting them back into service.
 
1 - 15 of 15 Posts
Top