Cleaning brake line to go from DOT 5 to DOT 4

[klammer76]

Last year I slowly put together the parts to convert the front brakes on my 2002 FLHTC to the 2008 and up Brembo brakes. Have the Brembo calipers, rotors and master cylinder. I have a braided Magnum Shielding brake line that was part of my stock 2002 brake system. The line consists of a lower and upper line that is connected in the middle by threading the two together. I need to get a new lower line but the upper line is the same. My stock 2002 brakes used DOT 5 and the Brembo's use DOT 4. Will it be ok to use the upper line if I flush it out with denatured alcohol to flush the DOT 5 out? The line has been on since 2008. New upper line is around $70 so would like to use the old upper if possible but I know that DOT 5 & 4 don't mix. If it's not advisable I will just get the new upper line.

Thanks,
klammer

[JC 92FXRS]

Your fine...just clean the old line really well and re-use it. Use brake-cleaner or alcohol or acetone. No worries.
Just make sure its clean.
Cheers, jeff

[06roadglide]

I converted my 06 back to dot 5 years ago. Got tired of paint peeling around master cylinder.

[TN]

don't mean to jack this thread but while brake fluid compatibility is the topic. Would it be ok to replace the dot 4 in my bike to dot 5.1. higher boiling point is reason. Don't see why it wouldn't work, even on ABS systems.


TIA


TN

[86fxwg]

don't mean to jack this thread but while brake fluid compatibility is the topic. Would it be ok to replace the dot 4 in my bike to dot 5.1. higher boiling point is reason. Don't see why it wouldn't work, even on ABS systems.


TIA


TN

Yes 5.1 compatible with 4.

86

[klammer76]

I converted my 06 back to dot 5 years ago. Got tired of paint peeling around master cylinder.

I know. I like the fact that the DOT 5 doesn't harm the paint but it seems to be hard to get the very firm lever feel that the 4 has? How did you clean the calipers, lines and master cylinder to convert back? Rebuild kit for master cylinder would be no problem and cleaning with denatured alcohol or electrical cleaner (?) but how did you clean out the calipers? No rebuild kits for the Brembos I am told. Looks like you can get seals on ebay though.

Disregard, just saw you have an 06 so you have the older style calipers (Kelsey Hayes ?) that had dot 4 in them or did you also convert to 08 & up?

[klammer76]

don't mean to jack this thread but while brake fluid compatibility is the topic. Would it be ok to replace the dot 4 in my bike to dot 5.1. higher boiling point is reason. Don't see why it wouldn't work, even on ABS systems.


TIA


TN

Yes 5.1 compatible with 4.

86

Is 5.1 hard on paint like 4 is?

[rbabos]

don't mean to jack this thread but while brake fluid compatibility is the topic. Would it be ok to replace the dot 4 in my bike to dot 5.1. higher boiling point is reason. Don't see why it wouldn't work, even on ABS systems.


TIA


TN

Yes 5.1 compatible with 4.

86

Is 5.1 hard on paint like 4 is?

If compatible with 4, then yes it would be. Only the silicone base 5 is safe for paint.
Ron

[86fxwg]

Just went thru an ABS class & this was discussed.
But why the confuse people with 5.1? Why not call it 6.0 or 6 
Me myself would opt for 5 if u don't have ABS! Higher boiling point,won't hurt paint,doesn't draw moisture.

86

[tmwmoose]

I did the same brake swap years ago on my 02 but stayed with dot 5 without nary a problem dot 4 sucks

[kd]

Isn't brake fluid water soluble? I've always used water for clean-up and flushing to prevent solvent damage to components.

[JC 92FXRS]

I had assumed the OP was switching to DOT 4 because the new Brembos were ABS and required DOT 4. If not ABS, can't imagine why one would switch from 5 to 4.
As far as cleaning up with water, DOT3 DOT4 not too bad (Glycerol based), DOT 5 not as well (Silicone based). DOT3 4 will absorb water, DOT 5 will not.
Jeff

[kd]

 

[fbn ent]

This was discussed on a few threads....I believe the majority recommended using ethanol (ethyl alcohol) to clean the lines/calipers before changing to DOT 4. It's hard to find in Canada but apparently easy in the US.

[kd]

This was discussed on a few threads....I believe the majority recommended using ethanol (ethyl alcohol) to clean the lines/calipers before changing to DOT 4. It's hard to find in Canada but apparently easy in the US.

I think the best place to find it is the pharmacy (by the gallon or 4 liter jug). There are some places that don't have the large volume containers because of the shipping hassle with Dangerous Goods Regs. It also has been removed from most retail shelves because it was popular for making stove top hash oil. It caused lots of explosions and bad fires.  Auto suppliers have it but it is not usually clearly labeled as such to discourage purchases for illegal uses.

[06roadglide]

I converted my 06 back to dot 5 years ago. Got tired of paint peeling around master cylinder.

I know. I like the fact that the DOT 5 doesn't harm the paint but it seems to be hard to get the very firm lever feel that the 4 has? How did you clean the calipers, lines and master cylinder to convert back? Rebuild kit for master cylinder would be no problem and cleaning with denatured alcohol or electrical cleaner (?) but how did you clean out the calipers? No rebuild kits for the Brembos I am told. Looks like you can get seals on ebay though.

Disregard, just saw you have an 06 so you have the older style calipers (Kelsey Hayes ?) that had dot 4 in them or did you also convert to 08 & up?

I stayed with my original calipers and master cylinders.
The master cylinders I rebuilt with with new older parts for bikes that were factory dot 5.
Popped calipers apart and cleaned, flushed lines with brake cleaner.
Used all old parts in calipers. Been about 5 years ago or more. No problems other than the usual front calipers need cleaning due to build up and Pistons not traveling freely causing excessive lever travel.

[06roadglide]

I had assumed the OP was switching to DOT 4 because the new Brembos were ABS and required DOT 4. If not ABS, can't imagine why one would switch from 5 to 4.
As far as cleaning up with water, DOT3 DOT4 not too bad (Glycerol based), DOT 5 not as well (Silicone based). DOT3 4 will absorb water, DOT 5 will not.
Jeff

OP bike is a 2002.  No ABS

Brembo caliper doesn't care what type fluid is in it as long as it's not contaminated. It's hydraulics.

But your right about the ABS. I wouldn't switch an ABS system without being absolutely certain the ABS module can work with the new fluid.

[fbn ent]

This was discussed on a few threads....I believe the majority recommended using ethanol (ethyl alcohol) to clean the lines/calipers before changing to DOT 4. It's hard to find in Canada but apparently easy in the US.

I think the best place to find it is the pharmacy (by the gallon or 4 liter jug). There are some places that don't have the large volume containers because of the shipping hassle with Dangerous Goods Regs. It also has been removed from most retail shelves because it was popular for making stove top hash oil. It caused lots of explosions and bad fires.  Auto suppliers have it but it is not usually clearly labeled as such to discourage purchases for illegal uses.

After looking everywhere else in this one horse town, I found it at Home Hardware. Sold as a fireplace/heater fuel.

[klammer76]

I am converting my 2002 so no abs. Biggest reason for going with dot 4 is the calipers are take off's so they have dot 4 in them. Can I effectively flush out the dot 4 from the calipers without total disassembly? Seals etc are not available from HD but believe they are from ebay? The master cylinder I can disassemble, clean with alcohol and reassemble with a rebuild kit. I am also looking for the very firm fel at the lever and better braking over what I have. Yes, I have cleaned the calipers on a regular basis.

I think FSG has converted and uses dot 5 on his bike with the Brembo. I do have the newer style master cylinder which I believe has a different bore size than my 2002. This possibly will give me the much better lever feel than the 2002 even when using the dot 5 ( I think Max alluded to this is a thread from a while ago). I agree, dot5 seems to be better with the non moisture drawing and not hurting paint. If I can get the dot 4 flushed out of the calipers I would definately consider staying with the dot 5.

Anyone flushed dot 4 from used Brembo calipers?

[fbn ent]

"dot5 seems to be better with the non moisture drawing and not hurting paint."

THAT is a major issue for me....of course with the masses going to chrome controls at least the paint coming off the master cylinders isn't a biggy. 

[JC 92FXRS]

If the Brembo's had DOT 4 in them, you might be better converting to DOT 4. Cleaning the lines and MC is easier than tearing down the calipers. DOT 5 will still give good brake feel, but you have to be really careful about agitating the stuff...if you drop a closed bottle of DOT5 on the floor, put the bottle on the shelf and walk away for two days  because it will have millions of little bubbles suspended in it which have to clear out before you use it. Carefully done its works as well as DOT4. I like DOT5 because is doesn't hurt paint and, in fact, it's brilliant when rubbed on wrinkle-black finishes (my calipers are wrinkle-black and they look factory)...blacks them right out and stays for a long time (another good point with DOT5). If you spill DOT 4 on a finish and don't notice it...the finish is gone.
Long and short, either will work...just have to be clean!!
Cheers, Jeff

[HD95]

Klammer,I just did the same brake up-grade to my 03 EGC,you'll need a new style banjo bolt at the master cylinder as well,it's a shorter banjo bolt.

[klammer76]

Klammer,I just did the same brake up-grade to my 03 EGC,you'll need a new style banjo bolt at the master cylinder as well,it's a shorter banjo bolt.

Thanks for that info, I'll pick one up. Did you go with dot4 or with dot5 with yours? Are you happy with the up grade?

[klammer76]

I have a friends 2008 shop manual. Manual does not address taking the calipers apart at all, apparently they consider them to be non serviceable and to replace if you have a problem. Probably Brembo and not Harley if I had to guess.

That being said, has anyone here split the calipers apart or removed the pucks, cleaned and re installed the parts?

Thanks,
Klammer

[lt1-xjs]

I did the same brake swap years ago on my 02 but stayed with dot 5 without nary a problem dot 4 sucks

Same here, pushed the piston on the 2014 Brembo all the way back to expel the Dot 4. Poured in some denatured alcohol and blew it out with air a few times. Filled and bled with new dot 5, all is good.