Topic: If you are fixing your bike with silicone...

[754]

There certainly are uses for JB and silicone..
 GE silicone is or used to be gas proof, many were not. If you dont believe it, put some gas in a beer can, poke a hole in it, then  silicone the hole, and it should setup with the gas against it.

 I use it on gaskets all the time, and never had a problem.. Dont use it for gaskets if you dont understand the word "sparingly" If you dont apply sparingly, EXPECT problems. I use a smear, not a bead..

[octagon]

i agree it's not a miracle cure for anything, but for repairing cracked sidecovers, jb weld works very well.
if you clean the inside surface around the crack, and sand it lightly, you can apply say a two inch band up and down the crack, one inch on either side. then press a two inch strip of ordinary woven fiberglass (the stuff you get at walmart for use with polyester resin) onto the jb weld. the epoxy will soak into the fiberglass. it's better to use gloves. if you moisten the fingertips of the gloves very slightly no epoxy will cling to them.
the five minute version of jb weld would probably be fine for this but i always use the slower curing kind because it's so much stronger.

  

[Spiider]

I need to disagree with you Kong...my HM300s exhaust have had their small rust pinholes sealed using JB Weld and after 2 yrs its holding well. I also had a CB750K4 with a broken cylinder fin repaired using JB weld and it held up fine over the years.

cheers
Andy

I agree, when i was working in a bike shop in Sydney i used Devcon {similar to JB} to rebuild brake master cylinders that had gravel rash or worn off corners from a slide down the road, when done properly and painted you couldn't tell the difference from new and i never had one fail....

Mick

+1 on the Devcon 

http://www.devcon.com/products/products.cfm?brand=Devcon&family=Aluminum%20Putty%20(F)

Best stuff to fix things like cracks in cases or even stripped threads. You can machine the stuff after a proper application.

[dave500]

i repaired the water cross over ports on an old aluminium v8 inlet manifold and i drove it for years,like 23,i upgraded to a new aftermarket edelbrock one and sold the old one privately telling the guy it needs welding,he was happy as he had already been duded on two ebay ones plus freight,i even had him drive around to my place and i tinkered with his qjet and he was more than happy,this was a 1969 holden five litre his dad bought new,some jerk mechanic in the day told his dad to remove the qjet and fit a holley 350 two barrel?what the?the manifold was a period correct part for his car.i think i had used "selleys liquid metal"

[daytonajoker]

I worked at a Honda shop in the early 70's and we fixed several CB750 crankcases with "MarineTex"when the drive chain hit them in front of the primary sprocket....we always told the customer....I never saw one leak....Recently I used JB weld to fix a 750 I bought from a guy who was told that he needed new cases....500miles later,it's fine....I used some fiberglass tape too between layers of JB...used brake cleaner and a wire brush to prep the surface....if it leaks, I'll split the cases and weld it,til then I'll keep my fingers crossed

[dave500]

yeah daytona the prep is the key,plenty of guys just pour goo over trouble and hope itll work,when it dosent they blame the product.

[somesuch]

i assemble crankcase halves with silicon,spead it on one side then smear lighty wiping off excess then press together,ive never had any show up in filters,i use more care than most maybe?

You, and Suzuki/Yamaha/etc...... they assemble their engine cases with their respective versions of silicone sealers.  The Suzuki 1207b silicone is very easy to work with, and I use it instead of gaskets on many engine covers that I may have to remove in the future. (assuming that the removal of the gasket thickness is not going to affect anything) Very quick and easy clean-up later with acetone if you need to get in there again. Use sparingly and carefully....Permatex import grey is also OK (but does not seem as good as 1207b) I also like Mercedes brand silicone sealer, but it is a bit thicker.

--Nick

[754]

Seems to me some gaskets you buy are "not fixed properly" due to the sealer sprayed on them..!!

[Tripps]

If you are fixing your bike with silicone, you are not really fixing it.

Unless you ride a Harley, then it comes in handy for sticking the bits that fall off back on. 

[Raef]

There seem to be a lot of bad vibes on this thread about silicon, what a lot of people don't realize is most car engines now a days are glued together, from factory, with a silicon type product called three-bond, there are a lot of engines out there that have a tappet cover gasket and head gasket and that is all, the rest is just stuck together with the three-bond.

most building race or hipo engines (auto) use it everywhere but the head and carb gaskets.

If it is showing up inside the engine it is being installed wrong and applied WAY to heavy.

with that said, there are not many places on a SOHC 4 that I would use it unless I was to hold a gasket in place or I was waiting on gaskets and planned on going back in.

I have never used JB weld on a bike but I whave cast small parts out of it with good results, it machines pretty well

Mark

[import_tuner13]

wait wait wait. i just stumbled in on this thread.     Digger!  i just sent you my carbs.  are these mine we are talking about here?  i dont' want no fake saggy silicone carbs coming back to me 

[SOHC Digger]

Don't worry, importtuner13, I wasn't talking about your carbs.  Yours just look like they have NEVER been apart... which is a good thing because it means nobody has screwed them up!

[Damfino]

.......you may be a redneck!