[Stevie Fierce]

i was screwing around with my 87 tecate today. i was able to locate a factory airbox a while back and today i wanted to mount it on the bike. it seems very clear that this aftermarket Keihin 39mm PWK carb that i have has a larger intake side than a stocker because that airbox was not fitting on there!!!! if this is the case what is my best bet with an airbox?? it seems i may just want to go with a stock carb. thanks for the help.
steve

 

[ezjman]

I know some guys take the intake for the airbox and put it in boiling water and stretch it around the intake bell of a bigger carb. It did not work for me. I run a 38mm mikuni right now and I got a piece of heater hose that was the same diameter of the carb and it would slide over the airbox intake boot. I had to make a ring that would go inside the airbox intake boot so when you tighten down with a hose clamp it would not crush the airbox boot. i am also able to use this set up when going back to the stock carb. I can post pics of it if you want. let me know

 

[tecates4ever]

im not sure what size carb i have on my 87 but i just forced it on there and tightened the clamp before the airbox boot poped off :tup:

 

[brose434]

putting it in boiling water to soften it up works. i've got 39mm pwk's on both of my t4s and this is how i got the boot to stretch over the inlet on the carb. it is helpful if you have someone helping to tighten the clamp while you have it forced on all the way otherwise it's hard to get the boot to stay on good enough to tighten the clamp.

 

[d'stecate4]

So the box and carb have to be installed as 1 unit? :hmm:

 

[Racerguy381]

So the box and carb have to be installed as 1 unit? :hmm:

You can take the boot out of the box an install it on the carb then bolt it back in the box with out much trouble. Just a pain getting to some of the nuts to take it in and out of the box.

 

[Stevie Fierce]

what about removing some of the excess rubber from the inside diameter of the airbox boot with a dremel and then heating it up to get it over the carb inlet? my airbox is no cream puff so I wouldn't mind doing this.

 

[Racerguy381]

what about removing some of the excess rubber from the inside diameter of the airbox boot with a dremel and then heating it up to get it over the carb inlet? my airbox is no cream puff so I wouldn't mind doing this.

I would be carefull with that one if you take to much it might tear rather than strech. If you want to try that find a replacement boot first incase you accidently destroy it. I thing the boiling water trick is your best bet. I have a 250R that had a PJ34 keihin on it stock and managed to strech the stock boots to fit a PWK 39 air stryker on it.

 

[370]

if the boot is old and dried out the boilig it trick probably won't work.. i'm nto sure how mine got stretched for a 39mm carb... but it wasn't the greatest plan whoever did it.. i like the ruber hose and support ring idea myself.

 

[rockhound]

I use a harbor freight exhaust tubing stretcher and a heat gun. i am sure to leave the stretcher in the boot until it cools completely so it doesn't shrink

 

[d'stecate4]

I have always just put a little wheel bearing grease inside the boot, helps it slide on and provides a better seal, I also put a little bit inside the air filter to.

 

[David Roberts]

The air horn (intake side of the carb) on the stock 35mm PWK is the same size as the air horn on a 39 PWK.
The intake boot shrinks with time and from fuel damage. Heat the boot up in boiling water as noted above or cut it and add a new piece of tubing.It's just what has to be done to cause these quads ate 25 yrs old.
We have the same problem on 20R's, LT250's and Banshee's.