Mudguards won't come off.

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Rooster1

I was right about that saddle
I would really like to take my mudguards off for a few weeks at least.

Bike, GIant Defy 2009.
Mudguards, Defy Specific

Problem1: The bolt from the back of the fork (A) through the forks to the front brake bolt (B) is seized.
Problem 2: In my efforts to release it, i've managed to round off the allen shape in bolt ( A) so I can't make a turn.

I can't simply rotate the brake round and round, as the mudguards are in place.
The actual thread that attaches to the brake is moving (would be easier if it wasn't)

Attempts:
I have tried pliers on the Bolt A to get some rotation
I have tried hammering gently on Bolt A (in the direction it needs to leave the forks)
I've tried overnight soaking in lube, oil, etc (on going)

So, do I just leave the the mudguards on forever
or destroy the front mudguard just so I can remove them

Shimano Ultegra Bolt Assembly

boltz.jpg


I might have to take it to my LBS if I can't fix this.
 

Globalti

Legendary Member
Here's what to do: set the bike up so that one end of the bolt is firmly supported. Then whack the other end hard with a hammer. The shock wil break the chemical bond that oxides have formed and you should then be able to unscrew the cylindrical nut by jamming something into the socket hole. Don't waste time faffing around with penetrating oil, that won't do anything until you've broken that bond and got things moving.
 

mjr

Comfy armchair to one person & a plank to the next
I'd be hammering but also applying penetrating oil before and after, hoping that as soon as the shock breaks the seal, it'll start to get in there. Cheap torx star bits are often recommended for hammering into rounded allen sockets but I've never got that far. There's always been enough for me to get a grip with a pipe wrench, vice or locking pliers.

And next time, should you grease the threads?
 
I have a 2009 Defy with mudguards. The bolt threads are exposed to cr*p thrown off the tyre through the gap in the mudguard. I've been here too - but was able to work the nut free with some WD40 and patience.

Not convinced that brute force will work. Try some focussed heat first - a mini gas blow torch may be small enough - you can get at the bolt up underneath the brake bridge once the guard is out of the way. You'll need to drill out the 2 rivets that hold the guard to the curved strip that holds the guard onto the brake bridge - not much room but should be do-able or if you have a Dremel, you should be able to grind off the top of the rivet - they are brass IIRC. That will get the guard off and you can re-assemble with a pop rivet from the inside. I've made a couple of sets of Defy guards from the wreckage of broken ones. They are very fragile anyway.

With the guard off, I'd try to cut the bolt. With the guard out of the way you should be able to get a Junior hacksaw blade in there up inside the steerer tube. Wont be quick or easy, but patience and a beer to hand will get you there. Maybe cross-drill the bolt first to reduce the depth of saw cut you need.

Once you've cracked it, re-assemble with copper grease and flush some WD40 down the inside of the steerer tube once in a while! If you take the tube top cap off you can see the bolt at the bottom - usually covered in road cr*p.

Good luck!
 
OP
OP
Rooster1

Rooster1

I was right about that saddle
I have a 2009 Defy with mudguards. The bolt threads are exposed to cr*p thrown off the tyre through the gap in the mudguard. I've been here too - but was able to work the nut free with some WD40 and patience.

Not convinced that brute force will work. Try some focussed heat first - a mini gas blow torch may be small enough - you can get at the bolt up underneath the brake bridge once the guard is out of the way. You'll need to drill out the 2 rivets that hold the guard to the curved strip that holds the guard onto the brake bridge - not much room but should be do-able or if you have a Dremel, you should be able to grind off the top of the rivet - they are brass IIRC. That will get the guard off and you can re-assemble with a pop rivet from the inside. I've made a couple of sets of Defy guards from the wreckage of broken ones. They are very fragile anyway.

With the guard off, I'd try to cut the bolt. With the guard out of the way you should be able to get a Junior hacksaw blade in there up inside the steerer tube. Wont be quick or easy, but patience and a beer to hand will get you there. Maybe cross-drill the bolt first to reduce the depth of saw cut you need.

Once you've cracked it, re-assemble with copper grease and flush some WD40 down the inside of the steerer tube once in a while! If you take the tube top cap off you can see the bolt at the bottom - usually covered in road cr*p.

Good luck!

I can tell you've been there already. I'm on my 2nd set of mudguards also. I like the idea of dismantling the guards from the rivet and bracket. I will give the bolt one last go this evening. Looks like we have rain coming anyway!
 

fossyant

Ride It Like You Stole It!
Location
South Manchester
So its the OPs fault the sun has gone.....
 
Protecting the sensitive bits of the bike are one of the reasons for mudguards, so what genius at Giant designed that one then? :wacko: :o) or :banghead:?

There's so little clearance under the brake bridge that both front and rear guards have a a metal plate with a central gap and the plastic guards then rivet onto the ends of the plate. The plate then has a curved tab riveted on that connects to the brake bolt. It's a poor design - but without the gap a continuous guard would simply not fit under the brake bridge and allow a 25 tyre to fit (or at least my Continental Hardshells - which I use to keep the hawthorns at bay) May be OK with a 23.

As it is the front guard (in particular) clogs if there's any soft mud on the road - the tyre picks it up and it jams under the brake ridge - sometimes I have to stop every few miles to clear the blockage - which is why I ride my 'bent in the winter now and leave the Defy in the warm and dry. Wintertime here means that the ever-larger tractors run on the verges and scatter mud all over the road, so the rural roads are perpetually filthy between September and April.

The Defy is a really good bike but it's a marginal fit for guards - and only the Defy guards will fit. Even then, it takes me a couple of hours to fettle a new set - which is why I've essentially made my own from a collection of bits to maximise the clearance.
 
Have you got a spare Allen key that fits? Try supergluing it into the rounded off hole.

Haven't tried it myself, but I have seen it suggested that a "Torx key" works better. Drive the key into the socket with a little brute force and the splines give enough grip to move the bolt
 
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