One man's musing about intake boots

Okay, I'm just going to throw this out there, being that the internet provides some anonymity.

Aren't the intake boots a rubber connector that's sort of vulcanized on to an aluminum flange? Couldn't we find a suitable thick rubber hose that would fit over the carb and slip over an old oem intake boot that's stripped down to the aluminum flange part that bolts to the head? In other words what if you cut off all the rubber from it and found a way to adapt it to the carb opening? Has anyone ever tried cutting one apart to see what it looks like without the rubber?

It's probably crazy talk. Go easy on me.
scott

 

I don't think anyone has. Most likely would work as long as your using fuel resistant rubber like a gas filler hose on a car.
Thing is, the original intake boots have a lip that fits into a recess on the carb throat to help hold the carb in place.
TCBrothers has something like your talking about for the XS650, don't know if they will work on the XJ's.
http://www.tcbroschoppers.com/xs650-bil ... folds.html

 

How about a catylised polyurethane or silicone molding? Both materials are up to the job. Any color you want too.

A lost wax or a three part permanent aluminum mold.

Are all four intake tubes different?

 

Well, yeah.......they are different-----

Each bike has different shapes,length, angles for them. Plus, on the 80/81 they were non-YICS, the 82/83 were YICS.....that means that the later ones were this configuration: //\\ rather than the //// of the earlier ones.

Also, you have to keep in mind that the vacuum port comes out the top. So, you'd have the flange, the rubber part, the port.

Seems to me the easiest thing would be to just order some new ones from Len........

Dave Fox

 

hell yeah!

 

On some models, yes, all four are different. On most models, it's a LH/RH type of arrangement.

The real issue is that the rubber sections....besides the internal lips to secure the throats....also have compound bends to them. If you have one off the engine, you can easily see what I'm talking about by laying the flange on a flat surface (tabletop, etc.) and then looking straight down onto/into it. The flanges start out straight/perpendicular to the tabletop (cylinder head), but then curve "up" and "inward" (towards the centerline of the bike") throughout their length. This is to insure proper mating alignment with the carb throats, and thus a leakless seal.

In other words, the centerlines of the intake ports (in the head) are NOT the centerlines of the carb throats. This situation may not be true for the XS models (which is why they can get away with the (perpendicular) billet manifolds and straight hose sections).

 

Wow! I'm glad I raised this although, now I think the point that Chacal raised is the one that makes it seem like it's not practical. It's such a short distance to be able to make bends in two different directions and still be able to get an airtight seal. Anyway - fun to muse.
Scott