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Induction Boots

Wez_

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FYI, the boots are different for the 750 as vs. the 900 and larger. On BOTH ends of carbs. They WILL interchange though. The intake manifolds up front are bigger for the bigger carbs and the backs are slightly different to reflect the different induction overall tuning in the airbox. ALL of the engines are somewhat touchy about the length after the carb to airbox, one reason why the airbox is better than pods. The engines like around a 50 mm. length on the end of the carbs. It seems to sharpen up the carb jetting spec.

Anything from '79-'83.
 
For a couple dollars more you can get new aftermarket boots that will be much more pliable and less prone to leaks than any 35 year old rubber parts you will find:

http://www.vintagecb750.com/products/6/fuel-system/54/carb-holders-air-box-rubber-boots-clamps

The ebay parts you linked to add up to $112.45 (with shipping)

The aftermarket ones I linked to will run you 131.90 (plus shipping)

New ones straight from Honda will set you back $127.04 (plus shipping):

http://www.hondapartsnation.com/oemparts/p/honda/16211-425-000/insulator-1-carburetor
http://www.hondapartsnation.com/oemparts/p/honda/16212-425-000/insulator-2-carburetor
http://www.hondapartsnation.com/oemparts/p/honda/16213-425-000/insulator-3-carburetor
http://www.hondapartsnation.com/oemparts/p/honda/16214-425-000/insulator-4-carburetor
http://www.hondapartsnation.com/oemparts/p/honda/17253-425-000/tube-a-air-cleaner-connecting (you'll need two)
http://www.hondapartsnation.com/oemparts/p/honda/17254-425-000/tube-b-air-cleaner-connecting (you'll need two)


Even if the aftermarket or OEM shipping cost were $20 I think used ones would be a bad idea. Vacuum leaks can cause all sorts of problems that are difficult to diagnose and old hard rubber boots are more inclined to leak.

:thumbsup:
 
Hi guys
Also have issues of hardened carb rubbers, from head to carbs.
Is there not a way we can soften them up somehow to reuse them?
We're a little out of the way here, and we take ages to source and land parts here. We in
Newcastle, South Africa.
Thanks in advance guys
 
Hi guys
Also have issues of hardened carb rubbers, from head to carbs.
Is there not a way we can soften them up somehow to reuse them?
We're a little out of the way here, and we take ages to source and land parts here. We in
Newcastle, South Africa.
Thanks in advance guys

Heat is the best way.

Have everything ready for a quick install (I'd even do a test run to make sure everything was ready and in a good place to be reached easily) Stick em in the oven on about 175 until hot then install them as quick as possible before they cool off. The moment they contact the head the heat will start transferring out (while wearing some nice gloves that allow you to pick up hot stuff without getting burned but also allow you to feel wtf your doing).

There are several other Home Remedies for this. Soaking them in ATF, Xylene, Wintergreen Oil, etc etc etc. The problem with all of them including heat (which does the least damage to the rubber IMO) is that the rubber will quickly return to it's hardened state and if they aren't sealed before they do, they won't seal after.

Myself, I prefer the "tons of WD-40" plus a few 2x4's and 2 big ass C-Clamps to press the carb rack into place without softening anything.
 
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