Mark on carb (insulator) boots

bdento59 · Post by **bdento59** » Mon Jul 21, 2008 4:52 pm

Hi guys,

I'm getting ready to install my carbs with a Staat board (Staat, S.; CBXpress, 2004, Fall, Vol 24, #3, p32) that I fashioned about a week ago, and I have one question before I pop 'em in. In the article referenced above, Steve mentions that, "... there is a mark (on the carb insulators) about 3/16" long and 1/16" wide that should be positioned at the top, otherwsie the spacing between the carbs is violated". I'm looking closely at my carb insulators and I see two "lines" that are 180Âº apart on the outside, but they look like lines from the molding process. There are also two other marks on each boot; a little diamond laying on it's side that's about the right size (3/16 x 1/16), and a two digit alphanumeric right next to it. Two of the boots have a "d3", two say "d5" and the last two say "d7". If these marks mean anything, the po paid no attention because they are not installed in any particular sequence or orientation. Some of the diamonds are facing the carbs and some are facing the head. Any idea what Steve Staat was refering to and if so pls advise, thanks.

alimey4u2 · Post by **alimey4u2** » Mon Jul 21, 2008 6:50 pm

I can't help you there bdento59 as I run none stock rubbers. I'm sure someone will come along soon with an answer.....

EMS · Post by **EMS** » Tue Jul 22, 2008 7:56 am

The marking of the boots only refers to the Prolinks. The rubbers on 81 and 82 bikes are wedge-shaped to allow the carbs to be installed in a more horizontal position. Therefore, the boots have a small oval mark on the wide side on the center raised ridge, which when positioned at the top will orient the boot correctly. If you don't have the marks and have a Prolink, you may have the wrong boots. This may give you a problem if you run a stock airbox. The carb intakes will not align properly with the airbox. If you run filter pods (which you shouldn't with CV carbs), forget about the mark. If you have a 79 or 80, forget about the marks.

Here is a picture: Prolink manifold on the left, 79/80 manifold on the right

bdento59 · Post by **bdento59** » Tue Jul 22, 2008 11:42 am

EMS wrote: If you have a 79 or 80, forget about the marks.

Here is a picture: Prolink manifold on the left, 79/80 manifold on the right

EMS, I have an '80, so no problem. Thanks for the insight.