White Plastic Diaphragm Plate Front Master Cylinder

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Ziggy

Member
I am looking for a front master cylinder diaphragm plate (The whitish plastic piece) that fits over the rubber diaphragm part # T2026017.
The part #2026017 was used on a multitude of bikes...But I can't find the white plastic piece that fits over top of the rubber on any parts schematic.

Anyone have one laying around that they would like to sell?

I am unable to find the part number of the piece. If you have the part number, it would be helpful.
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The part number for the front brake master cylinder cover is T2026006 which uses a T2026017 diaphragm. This is listed on bike bandit for a 2016 Thruxton and Thruxton R.
I believe the price was $18.60 which is probably thr same price a Triumph dealer would sell it for.
 
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The part number for the front brake master cylinder cover is T2026006 which uses a T2026017 diaphragm. This is listed on bike bandit for a 2016 Thruxton and Thruxton R.
I believe the price was $18.60 which is probably thr same price a Triumph dealer would sell it for.

Unfortunately, neither one of those part numbers are for the plastic cap. The plastic cap is not listed on the Schematic for the '16 Thruxton although the plastic piece does exist ...somewhere.
T2026006 is for the top metal cover for the master cylinder and
T2026017 is for the rubber diaphragm.
Thanks for trying though.
 
Ziggy your problem finding this part really peaked my curiosity. I took the cap off my front brake reservoir and sure enough there was the white plastic piece you are trying to find. I stopped by my dealer and there is no part shown like this on the parts diagram as I am sure you already found out. The service manager was at the parts counter and this part is part of the reservoir on many Triumph models just like you said. They have never had to order any of these reservoir/master cylinder parts so the question has never come up. They both suggested the part probably comes packaged with either the cap or the rubber diaphragm but they didn't know which. If I were you I would go to Triumph customer service and send a picture with the e-mail and see if they can find out for you which other part of the front master cylinder this part is packaged with.

John
 
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Ziggy your problem finding this part really peaked my curiosity. I took the cap off my front brake reservoir and sure enough there was the white plastic piece you are trying to find. I stopped by my dealer and there is no part shown like this on the parts diagram as I am sure you already found out. The service manager was at the parts counter and this part is part of the reservoir on many Triumph models just like you said. They have never had to order any of these reservoir/master cylinder parts so the question has never come up. They both suggested the part probably comes packaged with either the cap or the rubber diaphragm but they didn't know which. If I were you I would go to Triumph customer service and send a picture with the e-mail and see if they can find out for you which other part of the front master cylinder this part is packaged with.

John
Right, Been to 2 Triumph dealers in PA and 1 in NY. All 3 told me the same thing..."if it's not on the parts schematic, it doesn't exist".
I know it exists because I have seen it on other different Triumph models but not located on their schematics.
Should anyone find this piece anywhere, please advise and thanks.
Ziggy
 
Why not try a salvage yard? Surely they have Triumph master cylinders just laying around. Hell, they might even GIVE you that piece.
 
Why not try a salvage yard? Surely they have Triumph master cylinders just laying around. Hell, they might even GIVE you that piece.

Seems like I've searched the world over, can't be located.
If any of you have this piece on your front master cylinder, please let me know year and model of your bike.
Thanks,
Rich
 
The part number for the front brake master cylinder cover is T2026006 which uses a T2026017 diaphragm. This is listed on bike bandit for a 2016 Thruxton and Thruxton R.
I believe the price was $18.60 which is probably thr same price a Triumph dealer would sell it for.

I have located the part and it is T2026017 as stated by dynajohn.
A Triumph Dealer in Philadelphia had it in stock & took the time and pulled the part off the shelf. He sent me photos and it is exactly what I have been looking for.
It is indeed a 2 piece part - 1 Being the white plastic diaphragm plate and 2. the other piece is the rubber diaphragm.
It carries a $14.50 price tag for both pieces which are packaged together from Triumph.

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T2026017



















 
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Well, apparently my '16 Thruxton 1200 came through without the white plastic piece included in part number T2026017. It also appears some other Thruxton owners are also missing the piece and experiencing leakage on the front master cylinder as I was. I installed the white plastic piece 2 days ago...NO MORE LEAKS.
So of you are having this problem, order T2026017 and install the white plastic diaphragm plate along with the rubber diaphragm and your problem will be gone.
 
Seems like I've searched the world over, can't be located.
If any of you have this piece on your front master cylinder, please let me know year and model of your bike.
Thanks,
Rich
Rich and to the rest of you out there. This is called a Plate Diaphram and ALL front master cylinders have them The purpose of this is to create a seal between the cover and the rubber gasket on the Front brake master cylinder, without it, every time you squeezed the handle fluid would come out. So yes its IMPORTANT. Why anyone is having a hard time finding this is beyond me. YOU can go to www.motosport.com or bikebandit. put the year model and make your your bike in and you will get a page with a blow up of different sections of your bike, Each part is numbered. its idiot proof. This is NOT a hard to find part at all since every master cylinder on the planet has to have one. Just so you know.
 
Rich and to the rest of you out there. This is called a Plate Diaphram and ALL front master cylinders have them The purpose of this is to create a seal between the cover and the rubber gasket on the Front brake master cylinder, without it, every time you squeezed the handle fluid would come out. So yes its IMPORTANT. Why anyone is having a hard time finding this is beyond me. YOU can go to www.motosport.com or bikebandit. put the year model and make your your bike in and you will get a page with a blow up of different sections of your bike, Each part is numbered. its idiot proof. This is NOT a hard to find part at all since every master cylinder on the planet has to have one. Just so you know.
The problem is, the parts schematic/diagram does not show the white plate. It only shows the rubber diaphragm. It wasn't until a Triumph dealer in Philadelphia went and pulled the part (rubber diaphragm) off the shelf to discover that the white plastic plate is included with the rubber piece. My new '16 Thruxton came off the showroom floor without the white plastic plate and was oozing brake fluid around the cap of the master cylinder. Having owned well over 200 bikes, I knew the plastic plate was missing but without it showing on the parts schematic, it became a chore to locate one. Many dealers told me..."If it's not on the schematic, it doesn't exist." How wrong they were.
So, unless Triumph has changed the parts schematic you will NOT locate the white plastic plate by looking at said schematic.
 

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