Author Topic: Stiff carb rubber boots  (Read 1680 times)

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Offline gary p.

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Stiff carb rubber boots
« on: September 24, 2020, 05:19:08 PM »
I ordered carb air box rubber boots and carb holder set, expecting them to be somewhat flexible, as my old ones are hardened and probably beyond reuse.
The new ones are surprisingly stiff and difficult to bend.    I’m afraid they will make it a challenge to mount the carbs.
The last time I had the carbs off was in the 70s.   I think the original rubber boots were more pliable.

Am I remembering wrong?    Should the new boots be somewhat pliable?

Offline rb550four

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Re: Stiff carb rubber boots
« Reply #1 on: September 24, 2020, 05:47:03 PM »
  Yes. I run a hair dryer on them before removing them when everything is together to remove them easier. Heat them up again when applying them to the manifolds , then heating them all up before and when I push the rack of carbs back on . Hair dryer only ,not a heat gun they are too hot.
A few Honda 500's, a few Honda 550's, a few Honda 650's, '72 cb 450, a couple 500/550/650 hybrids, and 2001 750. 
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  http://forums.sohc4.net/index.php/topic,101678.0.html             
http://forums.sohc4.net/index.php/topic,137317.msg1550907.html#msg1550907

Offline BenelliSEI

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Re: Stiff carb rubber boots
« Reply #2 on: September 27, 2020, 05:58:17 AM »
If you set everything up and move quickly, I also find boiling them for heat works great. I have a large kettle in my shop. I hang them inside on bits of wire. Boiling for a few minutes gets them up over 200 degrees, but not too hot. They are also heated right through. If you are quick, carbs just pop on...

Offline Prospect

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Re: Stiff carb rubber boots
« Reply #3 on: September 27, 2020, 06:36:42 AM »
If you set everything up and move quickly, I also find boiling them for heat works great. I have a large kettle in my shop. I hang them inside on bits of wire. Boiling for a few minutes gets them up over 200 degrees, but not too hot. They are also heated right through. If you are quick, carbs just pop on...

That's a great trick. I'll have to try it next time.  I find getting them off the motor can be a challenge too. 
Current Bikes

1969 CB750  Sandcast #256
1971 CB750K1
1972 CB750K1
1975 CB400F
1975 GL1000 Goldwing
1954 Harley Davidson Panhead
1957 Harley Davidson Panhead

Toronto Canada

Offline gary p.

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Re: Stiff carb rubber boots
« Reply #4 on: September 27, 2020, 09:27:57 AM »
If you set everything up and move quickly, I also find boiling them for heat works great. I have a large kettle in my shop. I hang them inside on bits of wire. Boiling for a few minutes gets them up over 200 degrees, but not too hot. They are also heated right through. If you are quick, carbs just pop on...


Great idea, thanks for that.

Prospect, your going to need a larger kettle...

gp

Offline BenelliSEI

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Re: Stiff carb rubber boots
« Reply #5 on: September 27, 2020, 08:15:39 PM »
Taking them off is definitely option2: heat gun......

Offline ekpent

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Re: Stiff carb rubber boots
« Reply #6 on: September 28, 2020, 06:15:13 AM »
 Old hard 750 rubber manifolds can take quite a bit of heat from a gun and get somewhat pliable without damage but not sure on aftermarket possible Chinese rubber. Have quite a few 750's and have never replaced the manifolds but have upgraded the clamps.

Offline lash

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Re: Stiff carb rubber boots
« Reply #7 on: September 28, 2020, 06:24:48 AM »
I used a Sawzall once...carbs came off pretty easy!
Analog mind in a digital world..

Offline ekpent

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Re: Stiff carb rubber boots
« Reply #8 on: September 28, 2020, 06:39:47 AM »
I used a Sawzall once...carbs came off pretty easy!
That will get'er done   ;D ;D

Offline BenelliSEI

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Re: Stiff carb rubber boots
« Reply #9 on: September 28, 2020, 04:16:25 PM »
Dwayne...... I laughed even harder when I saw that was the “scrapper you have to take” you got from my barn! Still chuckling......

Offline lash

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Re: Stiff carb rubber boots
« Reply #10 on: September 28, 2020, 04:40:27 PM »
Little different now..
Analog mind in a digital world..

Offline BenelliSEI

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Re: Stiff carb rubber boots
« Reply #11 on: September 28, 2020, 04:57:37 PM »
Looking fine! I like that silver combo!

Offline lash

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Re: Stiff carb rubber boots
« Reply #12 on: September 28, 2020, 05:11:39 PM »
Im going to ride it over if it warms up again after this week..
Analog mind in a digital world..