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Shimano grx brake leaking
Hi tried to see if there was a thread about the shimano grx front break leaking at the "master cylinder / resivour ". So sorry in advance if I asking questions that have previously been answered. I recently purchased a new bike in December and to jump right to my problem. This is that it is weeping mineral oil from around the resivour seal is this normal?
Or what can I do to stop it leaking?
Would post a picture but not sure how to.
Thanks in advance for any advice.
If you're new please join in and if you have questions pop them below and the forum regulars will answer as best we can.
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In all fairness, it almost certainly NEVER happened…
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10 comments
Hi I think I have just worked out how to upload a photo
Hi Mark, from the picture you've uploaded I can tell that there is a serious dent in the reservoir body, probably from a pointy object that it hit on. I dont know if it can be replaced, I must look at shimano exploded view diagrams but, What is absolutely necessary to do is to contact purchase point and show them as soon as possible. If they admit that this is under warranty, they must repair it for you. If they somehow say that this is a damage you did with a sharp object as they always try do, blame the buyer, you can fix it by really cleaning it up , empty the reservoir somehow to the point it is not leaking when cleaned, not completely, and apply some sugru on it. Make sure it is not leaking while you do that as it will contaminate the bond between the frp body and the sugru. I assume that braking is firm and the leak is only on the reservoir (ambient pressure) and not in the actual closed hydraulic system (you would't have any brake at all). hope this helps.
Hi
Thanks very much I will contact the seller as I am really disappointed. I will let you know how I get on.
Thanks again
Never seen that before. Did you buy the bike new or secondhand?
Hi
Hope you well I bought the bike new. I had read about the grx group set and was waiting six months for it to come on the market. I am really disappointed with the left lever mechanism leaking as was so excited about grx groupset on a new bike. Any way I have contacted dealer so hopefully it will get sorted out.
Thanks for your advice fixit. I contacted dealer last night and they got back to me today. They will arrange courier to collect bike next and will change left brake mechanism. I will let you know how this goes. Thanks
Dealer also gave me the choice of rather than sending bike back to them They would send a replacement brake lever. This could possible benefit everyone. Any advice?
After a bit of deliberation decided to send bike back to dealer. It might be helpful for them to see if they can work out why and where lever is leaking. Anyway bike being picked up tomorrow.
I have exactly the same issue. Leaking under the lever. No visible damage. Unit around a year old and I noticed drop in performance a few months ago. Only just figured what was wrong when my hand started getting oily! Two year warranty so hope that Shimano will replace too!
Just for the record... I was given a replacement unit for the leaky one. New one worked well until one day the gear shifting became intermittent (even after reset). LBS mystified but definitely a fault with lever. Made another warranty claim - but no stock at Madison (UK distributor) until June 2022!! In the end i had to buy another one from Germany and await fdbk on warranty claim. At least when this lever is replaced I'll have a spare one for when the new one fails!