Brake fluid reservoir

Jeff Stich

True Classic
Since it would appear that the BMW and FIAT ones are made by the same company based on the similarity of the design...
They were initially designed/made by 2 different companies in 2 different countries ~17 years apart. In its original form, the design of the BMW reservoir is very different; only after modification does it appear more like the X1/9 reservoir. The only thing similar between the 2 reservoirs is their exterior length & width, which is the main reason why they're a good replacement (after modification) in the X1/9.

...it's likely the placement of the reservoir has a lot to do with the longevity. The X reservoir is subject to UV light while the BMW is under the hood and is almost never exposed to light, and as we know '70s and '80s plastics does not hold up to UV light all that well.
The X1/9 reservoir is hidden under the rear corner of the hood, away from direct sunlight (UV). It's the thin & poor quality plastic used that's the main issue with these. The BMW reservoir is definitely superior in this regard, especially considering the engine (bay) heat it's normally subjected to in its native use.
 
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beezee

True Classic
I ordered a new replacement from Henk. I agree with the thought that any used reservoir is close to end of life, and I don't want to repeat this job. So far I have replaced the clutch master and slave, brake master, and have had to drill out two caliper bleeder valves. I thought I had repaired the brake reservoir, but it ended up slowly leaking fluid which went through the drain pipe and onto the garage floor. The clutch line leaked at the master and ended up dripping fluid into the drivers footwell. I managed to cure that leak with a copper sealing washer.

Brian
 

dragonsgate

True Classic
Jeff Stitch is the member you want to PM.

Don't fart around with the two singles joined, it's a PITA. I got one of his BMW reservoirs & made my own bracket, moved inside & shortened hoses to fit.

Hey now Hussein,

There is nothing wrong with two tanks. At least I hope not. :eek: This is my 85X res set up. PO did this and it has not caused any problems to date. I think the 74s had 3 tanks IIRC.
View attachment 21640
I certainly hope not too. I have been looking for small reservoirs for my relocated MC but the prices I have seen are
ridiculous.
I just ordered three (two to use one to lose) from Lada and with shipping they are cheaper than single ones I have seen on Ebay.
Just hope they are decent quality.
 

Dr.Jeff

True Classic
Just hope they are decent quality.
I also bought some of those from the same source you did. I am still quite some time away from installing brakes so I have not tried them. But they appear to be fine. I am satisfied for what they are / what they do, and the price. I'll put it this way, I've seen MUCH worse for a LOT more money.
 

lookforjoe

True Classic
The problem I had is that the loop hose was an annoyance. Make it too short & it fails more quickly, too long & it's just in the way, IMO.

 

dragonsgate

True Classic
OK whats with the loop?
I figured I would just run a hose from each res to each cylinder on the master.
Is it to fill both bottles at the same time?
 

carl

True Classic
Just be sure you match nipple size of the small reservoirs to the MC as I believe the single reservoirs have nipples for a smaller diameter hose.
 

Coupefan

True Classic
We're all going to face this problem sooner or later. I nervously look at mine all the time. It's on it way out...can't predict when. In the meantime, I'm looking for solutions.
 

carl

True Classic
You might want to look into motorcycle brake and clutch reservoirs. Many bikes have stand alone reservoirs with a mounting hole and hose barb.
 

Dr.Jeff

True Classic
As far as hose and nipple sizes go, the single reservoirs I got (as in my earlier post) are correct. But that might differ depending what nipples you have on your master; I believe there are two common sizes used. However the master's nipples can be swapped for the other size if needed, the same source sells them as well (very inexpensive).
 

Dr.Jeff

True Classic
I purchased some motorcycle reservoirs to try, but the largest ones I could find are still WAY too small. Like a third the size of the small single reservoirs being discussed. I suppose they could be used, but you would really have to keep an eye on them so the fluid level does not get too low.
 

Dr.Jeff

True Classic
I'm truly sorry if anyone was offended by my last post, didn't know humour wasn't allowed, my bad.
I don't see any prior posts from you, guess I missed out on the fun. Humor is always a good thing, the problem is people that lack a sense of humor.
 

dragonsgate

True Classic
I purchased some motorcycle reservoirs to try, but the largest ones I could find are still WAY too small. Like a third the size of the small single reservoirs being discussed. I suppose they could be used, but you would really have to keep an eye on them so the fluid level does not get too low.
I didn't buy any motorcycle reservoirs but I think a couple of guys thought I was going to steal their bikes when they saw me scoping the res's until I explained what I was doing.
Came to the same conclusion as Dr.J
can't wait to get the ones I ordered and see how they work out and look.
The stock reservoir is holding fluid but I think duel res's would look more custom look.
I would like to have duel reservoirs mounted on top of the MC but don't have enough space between hood and cylinder.
I moved the MC into the frunk area and have the big reservoir mounted there now.
The picture is a bit dark but gives an idea of what I have.
IMG_2909.JPG
 
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