Honda CB750 Sandcast

The Restoration Shop => Fuel (gas - petrol) Tanks, Side Covers and Air Box => Topic started by: ashimotok0 on February 22, 2015, 07:04:28 am

Title: Carb inlet Rubber Treatment to soften with Reofos 508
Post by: ashimotok0 on February 22, 2015, 07:04:28 am

My video here: Works on nitrile rubber (ie Sandcast/K0 inlet rubbers ) don't believe it will work on PU (Sandcast/K0 Air box 'trumpets').


Immersion 18 hours at 70 degC in Refos 508 in a waterbath heated by a 'slow' cooker on top heat


https://www.youtube.com/watch?v=Y1kVSlLnR8k&feature=youtu.be (https://www.youtube.com/watch?v=Y1kVSlLnR8k&feature=youtu.be)

Title: Re: Carb inlet Rubber Treatment to soften with Reofos 508
Post by: Steve Swan on February 22, 2015, 10:40:33 am

Ash, is your prolonged treatment lasting ?  i've tried heating in past, certainly softens, but does not last.  BUT then, i have only soaked in hot water long enough to soften, not 18 hours.....

at the shop i worked at, we soaked 'em in "corn gas" here (ethanol) it lasts long enough to get them installed.

Title: Re: Carb inlet Rubber Treatment to soften with Reofos 508
Post by: kp on February 22, 2015, 05:15:24 pm

Try glycerol

Title: Re: Carb inlet Rubber Treatment to soften with Reofos 508
Post by: Steve Swan on February 22, 2015, 09:28:49 pm

Where do you get glycerol

Title: Re: Carb inlet Rubber Treatment to soften with Reofos 508
Post by: kp on February 22, 2015, 11:37:23 pm

In Oz it is a pharmacy product so maybe try your drug store. I believe Glycerin is the same thing which is sold in supermarkets but not in big quantities. I bought a set of rubbers treated with Glycerol and they are soft and reasonably pliable but I don't know what they were like before the Glycerol treatment. Rubber based items also have a much extended shelf life if stored in the freezer

Title: Re: Carb inlet Rubber Treatment to soften with Reofos 508
Post by: DW69K0 on February 23, 2015, 05:38:28 am

Here you go Steve-

http://www.ebay.com/itm/500mL-Bottle-Glycerol-Ultrapure-MB-Grade-99-5-Purity-Brand-NEW-Sealed-/161296902779?pt=LH_DefaultDomain_0&hash=item258e0b6a7b (http://www.ebay.com/itm/500mL-Bottle-Glycerol-Ultrapure-MB-Grade-99-5-Purity-Brand-NEW-Sealed-/161296902779?pt=LH_DefaultDomain_0&hash=item258e0b6a7b)

500 ml bottle.

Best,
Daw

Title: Re: Carb inlet Rubber Treatment to soften with Reofos 508
Post by: ashimotok0 on February 23, 2015, 08:49:39 am

The Reofos is used in the rubber processing Industry and re- plasticizes the rubber. I treated some K0 inlet rubbers in 2010 and they are still as supple today as when treated. BUT you need the long immersion at 70 degrees C. I gave ChrisR some and he did not have success but I think he tried it at room temperature and it definitively needs the heat. will post a video of the 2010 treated ones. To be fair the cost of new ones isn't too bad but a set for the K7/F2 are mega money

Ash

Title: Re: Carb inlet Rubber Treatment to soften with Reofos 508
Post by: Steve Swan on February 23, 2015, 10:16:12 am

Quote from: ashimotok0 on February 23, 2015, 08:49:39 am

The Reofos is used in the rubber processing Industry and re- plasticizes the rubber. I treated some K0 inlet rubbers in 2010 and they are still as supple today as when treated. BUT you need the long immersion at 70 degrees C. I gave ChrisR some and he did not have success but I think he tried it at room temperature and it definitively needs the heat. will post a video of the 2010 treated ones. To be fair the cost of new ones isn't too bad but a set for the K7 are mega money

Ash

Great stuff, Ash !