Author Topic: How soft should new carb boots be ?  (Read 1126 times)

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Offline greenjeans

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How soft should new carb boots be ?
« on: March 12, 2008, 11:24:24 AM »
Got some new carb boots in from Z1 and was expecting them to be soft....They are about like my old ones.
They came in sealed Honda parts bags, and while they looked new, they aren't soft at all.  They aren't quite rock hard, but they aren't far behind what I had.  Still have a bear of a time putting the carbs on.

How soft should new ones be ?   What about the boots that go between the carbs & air cleaner ?

When I heat those with a heat gun, they are very soft and rubbery while hot....should new ones be soft?

Did I just get some boots that have been on the shelf for 30 years ?
Yep, I'm the kid that figured out how to put things back together...eventually.

Offline 750essess

  • Orleans Cycle Repair & Resto
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Re: How soft should new carb boots be ?
« Reply #1 on: March 12, 2008, 11:29:48 AM »
They should be fairly soft, I can squeeze mine about a 1/8 - 1/4 inch between thumb and finger at the ends.
Orleans Cycle Repair and Restoration
76CB750F
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XR650L

Offline andy750

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Re: How soft should new carb boots be ?
« Reply #2 on: March 12, 2008, 11:42:18 AM »
I assume you are talking about the carb-engine rubber  - when new its still fairly stiff but should be pliable enough to get carbs on....its not going to be super-easy to get them on but will make it ....WD-40 sprayed lightly around boot also helps.....ALSO very importantly....make sure the rubber is aligned properly!! All boots have to be in the same vertical position  -this makes a HUGE difference....DONT align by numbers on top of the boots.....do it by eye and you will see the difference....they each orientate slightly differently and make sure you have right boot on right intake port 1/4 v 2/3.......the advantage of new carb-engine rubber is minimizes air leaks as in theory seal should be better.

Been there and done that -see my old thread....

http://forums.sohc4.net/index.php?topic=20733.0


The carb-airbox rubber should be much softer and getting airbox on/off should be really easy! #2 and #3 are the ones to watch as they always seem to cause trouble...and make sure the rubber sits in the airbox correctly - there is a little groove that should line up with airbox ports.

cheers
Andy
« Last Edit: March 12, 2008, 11:55:13 AM by andy750 »
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