VonCarlos

I think I have been successful at rejuvenating and renewing my original Mafac gum hoods.

I recently bought a 1972 Motobecane Grand Record that I believe was untouched.
I have just finished a complete disassemble/clean/touch-up/lube and replacement of critical parts like cables and bearings.

The only part that was a sore thumb, was the Mafac half-Hoods. They were getting old, dried out, cracked and a non-matching white (now aged tan) color. See what i mean?



I looked at replacing them with something from eBay, . . . but to expensive for my blood.
So, I took a gamble and decided to repair the cracks with a flexible and paintable caulking that I'm familiar with, DAP's Kwik-Seal. I applied it in several applications until it filled the cracks, let it cure for 24 hours in a 90+ degree garage and then started spraying them with a black colored, Performix "Plastic Dip" rubber spray coating. I probably applied at least 10 to 15 coats. Here are the results:







The caulking goes on rough and it's difficult to smooth out. I should have tried misting it with some water to smooth it out more, but I didn't want to invest too much time in this. The many applications of rubber paint eventually filled-in any rough texture. The rubber coating is quite durable . . . so far.
I was very rough with installing the hoods, brake-levers and handlebar wrap with no ill effect on the rubber coating. In fact, I sprayed these hoods over a piece of cardboard, and after all was dried, I pulled on the dried cardboard over-spray and it all pulled up as one piece!!! Here's a photo of the products I used:



I'm just about to take this Motobecane on a shake-down ride, so I'll follow-up on the durability of this experiment.

oggypop

I like this. I've been hoping for an advancement in gum hood surgery practices for some time now. Thanks for sharing.

scozim 

Quite industrious. I'm interested in the feel while riding. Does the rubber coating come in different colors?

frenchbikefan

yep https://www.awarehousefull.com/produc...stidip-aerosol

BentLink

You sir, are a craftsman!...looks like your patience paid off. Let us know after the ride.

lostarchitect 

This has me wondering if for all the effort expended, maybe you could actually make new ones.

frenchbikefan

I bet you could. put plsatic wrap in the hood, , fill a hood with something (plaster maybe?), wait for it to dry and take the hood off, then just do the process in reverse... eg cvoer, spray, and peel

mkeller234

I was pretty skeptical when I opened this thread but I have to admit that is impressive! I'm really interested to hear more about how they feel and if they are durable.

AZORCH

Y'know, I've been thinking about this very thing myself. I've got some white 600 hoods that I'd like to replace some day, but the replacement cost is outrageous. I did recently replace my C-Record hoods and bit the bullet. If someone else doesn't do this soon, I may just go ahead and give it a try to see if it will work.

sashimimi

I have been really wanting to try something similar with this stuff Sugru. I think it is very similar to silicone sink searler but could be pressed into a mold!

AZORCH

Hey, this is pretty interesting. Have you tried it with anything?

sashimimi

I havent, but it seems like it should be much more popular than it is. I think some have tried making grips, but I haven't seen any hoods. And a second.

Hangtownmatt

I confused. Wouldn't a pair of new gum hoods cost less than $10?

Matt

AZORCH

NOS hoods for some models can run 50 to 100 clams.

treebound 

And clams, like some hoods, get rancid as they age on the bike.

I might have to try the spray stuff on the gummy bear hoods on the Centurion.

snicker7

I have some 600 hoods that are *badly* cracked and not pliable at all anymore (sucks for putting on bar tape). When you do this, can they be stretched like original rubber or do they just start cracking again?

unworthy1

it's a nice fix and looks good cosmetically, but yes: if the underlying rubber is toast that will still crack when you stretch it. The over-sprayed coating and repair silicone (or latex) with probably be pliable, but they don't replace the old material.

Chombi

What if.......you dip a whole hood into Plasti Dip!
Do they make the stuff in clear? if they do, you can then retain the original color of the hood.
I was thinking one can do it on a set that's just starting to dry/rot out and maybe arrest the deterioration permanently(?) as you will keep air off the hoods for good.

Chombi

Snydermann

One of the contributors to the Lotus website sent me this photo of the leather brake hoods he made for his Supreme. I think he did an outstanding job.

The Thin Man 

Kudos on the frugal approach, however, I'd like to know what the result is after you've spent some time riding on them. Does the material easily come off? Does it rub off and stain your hands/gloves? Does it tear easily?

For cosmetic purposes, this could be really beneficial rather than dropping a mint on NOS hoods.

Thanks again for sharing!

cradom

I love those! Used to work in leather, might try something like that.

VonCarlos

Okay, I just got back from a shake-down ride.
Riding on 70psi. 1&1/4 inch tires is a dream! Oh so smooth!

The hoods look fine. The rubber coating I sprayed, is just that, it is rubber. It does not rub off on your hands or clothes and seems quite durable.
Here's a picture of me trying to tear and stretch it. As you can see it pulled up the cardboard first.





In my 90+ degree garage, I was able to spray a coat every 30 minutes and I probably sprayed about 10+ coats to get this build-up of material.
An important thing to do first, is clean the old hoods. You must clean off any oils or dirt that could hinder the bond. I used denatured-alcohol very gingerly but would suggest using isopropyl-alcohol or maybe just soap and water. The denatured-alcohol dried-out the hoods too much for comfort.

If you have questions as to the Plastic-Dip product, I refer you to their website. https://www.plastidip.com/home_solutions/Plasti_Dip

As to why I went to so much effort, which it wasn't, (clean-caulk-spray-done) I can tell you I am a person who likes to think outside-the-box and be creative. I like the way things use to be made, when you could open up something broken, replace the little 5 cent O-ring and have it work for another 20 years.

PS. I really like the look of the leather hoods and might just try that on my Legnano build.

Chombi

Dang! Those should last so much longer than any rubber hood, plus the leather will develop a nice patina with use.He should go into business and sell those things! They will surely sell like hotcakes, specially to C&V and Fixie crowds! I want a couple of set of those in tan too!


Chombi

VonCarlos

I think there is someone making these for sale, I remember reading a post here or at Classic Rendezvous about it.
One could also make these with any of the different colors tanned leather comes in.

unworthy1

Hear-hear! and kudos to VonCarlos and everybody who fixes things and keeps C&V stuff in service and out of landfill, and shares the details with others!
I'd love to know how he molds the leather for these (over a form he made or just over an old lever body?) as well as "how much for a pair"?