Topic: Front caliper assembly ? Lube or no lube?

[drumgod]

Wow TT.  You have an amazing amount of knowledge crammed into your head.  Your help is much appreciated!

I've been following this thread as rebuilding my master cylinder/brake caliper are on my list of things to tackle this weekend.  The main Napa warehouse in the US is about 15 minutes from me.  Does anyone know if Napa carries any products suitable for #2 and #3 as detailed by TT above?

Do any of the other chains carry suitable products?

Would a Honda dealer have them?

Thanks guys!

[Duke McDukiedook]

#2 you should be able to buy at a place like NAPA that provides parts/tools for REBUILDING automotive stuff. O'Reilleys/Auto Zone type places are not very good for these kinds of supplies.

#3 you'll probably have to buy online from a scientific supplier, that is where I bought mine.

[TwoTired]

Thanks that is great info.

Specifically this is the product I found.


The instructions say specifically it is for both the rubber seal and the piston and when applied to the back of the pads it will stop squeaks.

Good to 400F

Thanks for clearing that up.

Your welcome.

I am not familiar with that product, nor have I used it.  I don't see any ingredient list to assess, either.  Maybe it will work as required.  I can't endorse it for the SOHC4 caliper.

I will warn you about "specsmanship".  Saying a product will maintain lubricative qualities up to 400F, is different than saying it will maintain it's grease state to that temperature.  At 375F (or lower) it might just run into your brake pads and rotor and still be excellent lubrication there. 

To further clarify, you do NOT need a lubricant behind the brake pad or on the caliper piston.  What IS needed is a barrier between metal and water/oxygen that will stay put.  While the Dow grease does have some lube qualities, heat doesn't melt it, water won't combine with it.  Basically, it's perfect for the job and has been used for many tears in that application successfully.
I simply don't see the attraction of finding a substitute for what has proven to work as required.

Similarly, Brake parts assembly lube/fluid is the known, correct substance to be applied to the caliper seal component.  If some gets into the DOT3, no harm, no foul.  If some gets on the side with water, and/or humidity it will still block it's access to the caliper piston and cylinder wall, inhibiting corrosion.  The rest of the caliper metal will be protected by the Dow Silicone Grease.

Here is an added point to consider.  Brake fluid will crystallize over time, which is why it is replaced every two years.  If you've dismantled an old caliper, you probably found old crystallized brake fluid behind the caliper seal, along with aluminum oxide corroded from the caliper cylinder groove.  Bake assembly lube in the groove provides an extra barrier impeding the collection of Hygroscopic brake fluid in the caliper groove.
Regular fluid flushes won't replace the DOT3 in that groove, allowing it to crystallize anyway with time.  The longer you can keep DOT 3 (either dry or with water absorbed) out of the seal groove, the longer the interval needed between overhaul.

IMO, of course.

[MoTo-BunnY]

Thanks for all the info TT - well put and informative as usual.

I kinda got derailed there talking about the Dow grease when I see now it was more about the assembly lube. I just wanted to point out all the misinformation out there from the typical auto store and guys that have only worked on cars. When I was doing my first cycle brake job, without exception, every store I went to and every auto mechanic I knew and talked to recommended a wide assortment of off-the-shelf products to do my brakes with, NOT ONE OF WHICH, I NOW KNOW, WOULD HAVE WORKED CORRECTLY!  lol   

The info I got off the forum here allowed me to assemble it all correctly with all the correct fluids and greases. The information gained here literally saved my butt a couple months later when I had a close call emergency stop with an idiot that slammed on his brakes to try and make a turn he had already missed in the middle of a 45mph zone. The brakes performed flawlessly, as they continue to do three years later (with brake fluid changes, of course!) and I am still here today!   

[razor02097]

I do service my brakes when needed.  Changing out the fluid when it gets dirty, changing out the brake pads, and adjusting the rear shoes.  I just wanted the damn caliper together I didn't "rebuild" it per say as I didn't use new parts just cleaned it all up and put it back together.  

The WD-40 was just enough to make the piston slide in easy... from what I hear would be better then using brake fluid to assemble it.  My problem wasn't caliper sticking it was done when I changed out the brake pads.  I cleaned out a lot of gunk too.  The seal and piston had no signs of damage and did not leak.  After assembling and bleeding the caliper worked perfectly.  

Not saying never to use caliper grease just saying that I don't rebuild calipers hardly ever... not enough to warrant a $15 tube of grease that only is used for caliper seals.

On a side note even though the old pads and shoes still had meat on them the braking systems where a lot lot better with the newer pads and shoes.

[IHWillys]

I recently serviced the front caliper on the '75 CB550F.  I simply put it back together without any sort of lube/grease.  Works great, no worries.

Ken

[MoTo-BunnY]

I recently serviced the front caliper on the '75 CB550F.  I simply put it back together without any sort of lube/grease.  Works great, no worries.

Ken

Key words 'recently serviced' - Sorry, but we will see you back here in a year or two looking for help, when your front brake starts dragging from hygroscopic water contamination / corrosion . .  .    

[IHWillys]

...Key words 'recently serviced' - We will see you back here in a year or two looking for help, when your front brake starts dragging from water contamination / corrosion . .  .    

Well, if so, these Hondas must have crappy calipers as I''ve been messing with old street bikes for 20 years now and I've never had to use lubricant on the seals/pistons when reassembling a caliper.  I suppose I'm the lucky one.  

I'm still riding my RD400F upon which I last serviced the calipers(aside from pads) back in 1994.  Hmmm, still waiting for those two assembled-dry calipers to start "dragging from water contamination / corrosion".  Must be the superior Yamaha build quality...hehe.

Ken

[TwoTired]

 I suppose I'm the lucky one.  

Yes, either lucky or quite the story teller.    (sarcasm alert!!)

Let's see, I still have the original caliper on my 74 with no corrosion on the caliper. (the piston is a different story, corroded on the DOT3 side of the seal.)
Honda put silicone grease on/in the caliper so that corrosion wouldn't happen.  I guess your home remedy is far superior?
I'm thinking you probably should stay away from Hondas, being as they are so crappy, and all.
Ain't internet stories great?

Oh, hell, I might as well offend razor, too.  (Just to uphold my reputation and all as a butthead.)
WD40 is a petroleum product.  Does nasty things inside a DOT3 vessel.  If I recall correctly it forms into sticky globs over time.
Rebuilding and having it work "perfectly" right after the rebuild is NOT the point.  Rebuilding it and having it still serve 10-15years later IS the point of using the correct materials in a proper caliper servicing task.
Sadly, there are even Motorcycle shops that just make it work for the short term rather that do the job correctly and have it last 3-5 times longer.  Lot's of people just won't pay for quality work and materials, cause they just plan on throwing it away (or selling it) later anyway, so it will no longer pose a problem near term.  Of course, if you keep the bike 35 years like I do, you learn to place more emphasis on longevity of the repair. Flipping bikes for profit is quite another matter, and the sensibilities change if one passes on the long term problem to someone else.

Ah, whatever...  (I think maybe I've been on this forum too long.  Probably time to leave the asylum.) 

[razor02097]

TT you didn't offend me and you could be right about WD-40 but I didn't spray the whole thing out with it.  Plus replacing the brake fluid will flush such globs out.  I'm not holding my breath on keeping my 650 for 10 or 15 years; as the part availability dwindles with each passing day.  Engine rebuild for the redheaded step bike becomes less feesable as time goes on.  Once the piston and seal is discontinued then this caliper is junk.

The honest truth is I wanted to ride after soaking the caliper and cleaning all the crap out.  I'm not going to pull apart the front brakes now to apply some caliper grease.  Its much better then it was and if I have to do it over again in X number of years then so be it.  I just stated the way I got my caliper back together thats all.

I didn't say WD-40 is best, I didn't say that WD-40 was good; I said it was on hand plus it worked well to clean up the seals and shine up the piston.

[IHWillys]

...
Yes, either lucky or quite the story teller.  ...

Must be luck then because I don't tell "stories".  Anyone here can look up every post I've made here and many other sites I'm on under the same username and see that I don't BS.  I don't profess to be some great mechanic either, but do offer what I know and what I've experienced over the years.  The mentioning of "crap" per the Honda reference was tongue-in-cheek but the 'net loses so much in that regard.  Though I thought the "hehe" at the end would've sufficed to illsutrate my intent.  Oh well.

If you had read my post, you'd know that my "home remedy" is to simply not use any of the aforementioned lubricants on caliper seals and pistons, including brake fluid of any kind.   I assemble calipers dry and amazingly have them still functioning years later. 

Ken

[MoTo-BunnY]

...
Yes, either lucky or quite the story teller.  ...

Must be luck then because I don't tell "stories".  Anyone here can look up every post I've made here and many other sites I'm on under the same username and see that I don't BS.  I don't profess to be some great mechanic either, but do offer what I know and what I've experienced over the years.  The mentioning of "crap" per the Honda reference was tongue-in-cheek but the 'net loses so much in that regard.  Though I thought the "hehe" at the end would've sufficed to illsutrate my intent.  Oh well.

If you had read my post, you'd know that my "home remedy" is to simply not use any of the aforementioned lubricants on caliper seals and pistons, including brake fluid of any kind.   I assemble calipers dry and amazingly have them still functioning years later. 

Ken

To each their own, but I'm pretty sure assembling calipers 'dry' here in rainy Oregon wouldn't last too long - that water is going to get in there without the proper grease, no doubt about it.  Unless of course, you never see the rain on your bike but that's rather hard to plan in the NW.   

[Gamma]

Can't find Dow High vac grease here in saudi, but have access to xg250 silicon grease in thixotropic form (vaseline), not spray, what do you think TwoTired?

[Duke McDukiedook]

Can't find Dow High vac grease here in saudi, but have access to xg250 silicon grease in thixotropic form (vaseline), not spray, what do you think TwoTired?

You can't get it shipped to you in Saudi? There are no scientific instrument suppliers in the entire nation?
 

[JS550]

I ruined a new seal by trying to install not properly greased. So with the 2nd one I used a synthetic assembly lube & it went together fine. I thought the seal was so tight that you couldnt do it without the lube?
jim

[Duke McDukiedook]

I ruined a new seal by trying to install not properly greased. So with the 2nd one I used a synthetic assembly lube & it went together fine. I thought the seal was so tight that you couldnt do it without the lube?
jim

Hopefully you are using DOT5, if not you may have problems...

[IHWillys]

...To each their own, but I'm pretty sure assembling calipers 'dry' here in rainy Oregon wouldn't last too long - that water is going to get in there without the proper grease, no doubt about it.  Unless of course, you never see the rain on your bike but that's rather hard to plan in the NW.  

Aha... I was wondering if someone was going to point out where I live as a factor.  I live in Colorado as the FC CO indicates.  It's pretty darn dry here.  The bikes generally see more wet "weather" during cleaning than on the road.   Thus...

I have absolutely no idea how the method of dry assembly may fare in the the wet NW or other locales.
I do know, here in a semi-arid desert where I have lived since 1985, it has worked for me and has not lead to early failure.  In the future I will mention this caveat in any post of mine concerning this issue though I likely will just keep it to myself now that I see the overwhelming concensus is that I'm doing something wrong.  I don't wish to steer anyone in the wrong direction with any advice, let alone advice with brakes.

Hey, I think I will get some of this fancy lubricant as it certainly appears it doesn't hurt anything if the proper product is used.

I stand by my statements but I also stand corrected.

Ken

[TwoTired]

Can't find Dow High vac grease here in saudi, but have access to xg250 silicon grease in thixotropic form (vaseline), not spray, what do you think TwoTired?

Well, it >>sounds<< good.  Can you put a bit of it in the oven and see if it will puddle and run with temps approaching 500F ?

Second test is to put some in water and see if it will mix.  Pure silicone won't make any emulsion at all, leaving the water clear even if agitated.

Just about any grease will provide a film barrier for the exposed metal bits.  The "trick" it to have stay in place not creep or otherwise flow into the brake pads when cold or hot.

I did a quick internet search.  Is this the stuff?
"HTS Silicone Grease - for operations at low & high temperatures, water resistant, chemically inert, excellent insulating properties & long life span under conditions where conventional grease cannot be used. Meets FDA/USDA food grade requirements. Meets British Mil. Spec. XG-250. Temp. range -40 to 200°C."

If so, I'd give it the oven test.  When I did this, the Dow corning stuff hardly looked any different at 500F than it did when I put it inside at room temp.  Well, maybe it "glissened" a bit more.  (The sylglide was a small bit of brown tarry stain left on the aluminum foil.  Most of it had vaporised. )

[Gamma]

TwoTired
Yes thats the right product, I have a calibrated oven at work that will go to 800c (1472f) so I will test it on Saturday (thats the 1st day of the working week out here).

Dukiedook
I will not bore you with the problems I have, trying to restore a CB/CR750 in Saudi, needless to say I do bring back products from home and other places, but it is a lot more time consuming finding stuff out here, than ordering a part over the net or popping down to the bike dealer, or getting something off ebay.

[drumgod]

I don't know if this will help anyone else, but in one of TTs posts (in one of the many caliper rebuild threads) he gave this link for the "Hydraulic Brake Cylinder Assembly Fluid":

http://www.autoparts2020.com/rsdev/part_detail.jsp?PART_HDR_ID=40378

I spent about an hour trying to locate this stuff locally.  I found a distributer about 45 minutes from me but he would only sell by the case...  I gave up and went to buy it from the link above.  When I added it to my shopping cart it cave me a zipcode search for a local supplier.  Doh!  There's one about 15 minutes from my office.  They'll have it for me tomorrow.  I don't know what areas they have stores in, but the Chicago area has several options.  Try their store locator.

As for the "Dow Corning High Vacuum Grease", I really lucked out.  Some quick searching located a local lab supply house that carried it for $21.95.  Before buying some, I stopped by the maintenance dept. where I work... they gave me a couple ounces.   

[MoTo-BunnY]

People sell the Dow grease on the feeBay from time to time, especially real cheap if it has passed its "expiration date" which I doubt would affect it as per our usage of it. This grease is some wicked good stuff - I have also found it handy for other purposes such as lightly "lubing" each side of the neoprene gaskets I custom-bunny made for my points cover. (to help keep water out) 

All I know is that I have tried every trick in the book to keep H2O out of my bike, such as this grease, liberal amounts of dielectric grease in the wiring, etc. and it all seems to work great as my cycle doesn't miss a beat in driving Oregon rain. I ride in the rain a LOT too (not that I necessarily WANT to  . .lol. . . it's Orygun though, if you are afraid of rain then try the SW or Australia. .. lol)


Also, TT - so you are the one that did the oven test with various greases? I had thought it was HondaMan (unless he did it to) but if it was you, please let me know - I want to cite the correct source! (that test is so cool - well, hot actually)    That's what I love about this forum, is it's not a bunch of people just saying "I use this product, just because" or falling just for good marketing/NASCAR tie ins, blah blah blah - Instead, it's a bunch of Honda 'geeks' that have years of experience actually USING these tips and/or will actually take the time to do your own tests and back up what you're saying.   good stuff for sure. .  .I bet the enthusiasts of other makes/models of bikes are jealous of the intelligent resource here!

[TwoTired]

Also, TT - so you are the one that did the oven test with various greases? I had thought it was HondaMan (unless he did it to) but if it was you, please let me know - I want to cite the correct source! (that test is so cool - well, hot actually)   

I don't know if Hondaman did a test, too.  But, I did a Sil-Glyde/ Dow Corning oven test and posted a report to the old Mailing group list, probably over ten years ago.  Somewhere in my Lotus Notes Archives is...
....The original manuscript (Ha Ha)  I wonder if I can ever recover that from its database?  Oh well...

Cheers,

[JS550]

I ruined a new seal by trying to install not properly greased. So with the 2nd one I used a synthetic assembly lube & it went together fine. I thought the seal was so tight that you couldnt do it without the lube?
jim

Hopefully you are using DOT5, if not you may have problems...

I have DOT4 in it now. Should I switch it out for 5? & why? Just curious.
jim

[MoTo-BunnY]

Also, TT - so you are the one that did the oven test with various greases? I had thought it was HondaMan (unless he did it to) but if it was you, please let me know - I want to cite the correct source! (that test is so cool - well, hot actually)    

I don't know if Hondaman did a test, too.  But, I did a Sil-Glyde/ Dow Corning oven test and posted a report to the old Mailing group list, probably over ten years ago.  Somewhere in my Lotus Notes Archives is...
....The original manuscript (Ha Ha)  I wonder if I can ever recover that from its database?  Oh well...

Cheers,

Tests like that are MUCH appreciated!  you know like they say, SOHC4.net talks - BS walks  


I don't know how many mechanics I have talked to that go off all recommending some supposed god-like product (you know, to the clueless gal here, like we ALL are. . .lol) and I'm like "What's in it? (the product) Have you ever pulled up the MSDS on it? I bet it's just kerosene with a few additives." Their response: "ummmmm, well, errr. . ah. . . I heard it's good!  yeah, and it's named OUTLAW!"*  

*actual exchange about a year ago with a tweeker Harley dude recommending "Outlaw gas additive" . .  ..lol

[Duke McDukiedook]

I ruined a new seal by trying to install not properly greased. So with the 2nd one I used a synthetic assembly lube & it went together fine. I thought the seal was so tight that you couldnt do it without the lube?
jim

Hopefully you are using DOT5, if not you may have problems...

I have DOT4 in it now. Should I switch it out for 5? & why? Just curious.
jim

You don't want to mix DOT5 with anything else, keep the DOT4 in there if that is what is in there now.
The rationale being that you do not want to mix silicone with DOT3, 4 or 5.1. They don't mix with good results.