Questions on bigger carb

[crackshot]

What bigger carb will fit an 85 R ? Does the boot need to be changed to fit?

[TeamGeek6]

The boot is the main part. A larger carb needs a larger boot because the outlet is larger diameter. You can have a machine shop bore the old one, mine is bored +2.

Id suppose that engine would take a 40 or 42 at least. Try Pro-Flo on the Internet, they sell Keihin and had good prices last time I looked. http://www.pro-flo.com/

A swap would get rid of the problems with that stock PJ (piece o junk). Throw it under a pavement roller- thats where I wish mine was.

[crackshot]

Actually its a PE carb. I checked it when I rebuilt it.
BTW - You sig shows you have an 1986 R and a 140 degree thermostat?
I did not know they put thermostats in those years did they?

[Mr. Sandman]

What bigger carb will fit an 85 R ? Does the boot need to be changed to fit?
You can go up to a 38 or 39 mm carb and still get the stock intake and air filter boots on but they will be tight, and anything larger would require oversized boots and major motor mods for it to run right (a 38 or 39 would be way too much as well unless you're running major mods or you jet it way down). But, if the boots are in good condition with supple rubber and no cracks you can heat them in boiling water so they'll stretch and slip on easier. Or you can do the beer bottle trick. Heat the boot in boiling water and insert a beer bottle into the end of the boot. Let it cool, and repeat the processes 2-3times. Eventually, the boot will be stretched enough to make the carb install go quicker, easier and without multiple cuss words and pinched fingers.

[88 Turbo Coupe]

Rather than do the stretch thing where can I get an intake that fits a 38mm carb for my 250r???

[Bryan Raffa]

i used heat on my z boot went from a 32 to a 38 no problem after it was on for a couple days it kept its shape , it goes right on and off now.