Is this right?

SS109 · #1 04-05-2023, 11:26 PM

Curious if anyone could tell me if this is all I need to rebuild my AJP clutch master cylinder? Part #17 on the diagram.

(F5) · #2 04-06-2023, 04:31 AM

Yes, it's just that piston, but the rest is nice. If the cap says mineral oil then use mineral oil.

Do look inside the bore. I've cleaned brake ones before with 1200 wet and dry. Guess oli ones would be less likely to get corrosion damage.

Lube it before inserting.

Said the actress to the bishop.

SS109 · #3 04-06-2023, 09:49 AM

Thank you.

(F5) · #4 04-06-2023, 03:55 PM

Wait a minute. Where is the brake one then?

34 is incomplete but near the left side.
17 has all the right parts but is drawn in the wrong order and is in a dumb place because it's near the left, but just maybe its supposed to be the brake one.

Again, if you tried to put it together like that it won't work. What cretin drew this? and why didn't his supervisor check it?

Brake fluid is compatible with certain rubbers like Nitrile, but not with EPDM etc that are used in mineral oil systems often employed in clutch hydraulics.

gasgasman · #5 04-06-2023, 09:31 PM

You could ditch the AJP and go with a Magura master cylinder.

SS109 · #6 04-06-2023, 10:07 PM

Quote:

Originally Posted by (F5)

Wait a minute. Where is the brake one then?

34 is incomplete but near the left side.
17 has all the right parts but is drawn in the wrong order and is in a dumb place because it's near the left, but just maybe its supposed to be the brake one.

Again, if you tried to put it together like that it won't work. What cretin drew this? and why didn't his supervisor check it?

Brake fluid is compatible with certain rubbers like Nitrile, but not with EPDM etc that are used in mineral oil systems often employed in clutch hydraulics.

My problem exactly. I'm not sure of anything with these parts views and, sadly, this is on CPD Direct.

Quote:

Originally Posted by gasgasman

You could ditch the AJP and go with a Magura master cylinder.

I don't want to change to a different clutch master as I just bought new AS3 levers and they're already mounted. Plus, I won't be using it often on this bike as it does have a Rekluse but I do want it to work.

ditezz · #7 04-15-2023, 07:52 PM

Quote:

Originally Posted by (F5)

Yes, it's just that piston, but the rest is nice. If the cap says mineral oil then use mineral oil.

Do look inside the bore. I've cleaned brake ones before with 1200 wet and dry. Guess oli ones would be less likely to get corrosion damage.

Lube it before inserting.

Said the actress to the bishop.

The Mineral oil masters are MORE likely to corrode if moisture gets in as water doesn't mix with the mineral oil and pools in the master and causes corrosion. Brake fluid is hydroscopic and water tends to mix with the brake fluid .Its prudent to replace the clutch mineral oil every 6 months

SS109 · #8 04-15-2023, 09:03 PM

Quote:

Originally Posted by ditezz

The Mineral oil masters are MORE likely to corrode if moisture gets in as water doesn't mix with the mineral oil and pools in the master and causes corrosion. Brake fluid is hydroscopic and water tends to mix with the brake fluid .Its prudent to replace the clutch mineral oil every 6 months

Yeah, I'm familiar with how mineral oil is hydrophobic and the problems it can create. Luckily, I live in one of the driest places in the USA so I'm not overly worried. Regular servicing should make it last.

Anyway, I couldn't find a kit that I for sure knew would work so I went ahead and ordered a new master from CPD Direct. Should be here early next week.

That said, the price of a little 4oz bottle of mineral oil is ridiculous. I paid over $10 for that little bottle after I finally found a place that had some in stock. I've read where non-scented baby oil can be used, as it is a mineral oil, with good results. I know it is a helluva lot cheaper and readily available. Anyone ever use it?