Clamping on dropper post

[MudLark]

Weird. I only ever clamp a bike by the top tube. I only work on my own bikes though.

[guidodg]

40 minutes ago, MudLark said:

Weird. I only ever clamp a bike by the top tube. I only work on my own bikes though.

on aluminum bikes that is ok..on a carbon frame you are taking a big chance...

[madmarc]

In my opinion, bike repair stands are the worst design i've seen from an engineering point ye ye I know its an industry standard but for me clamping on the seat post / dropper post or the frame just doesn't sit well with all the work being done on the bike - spinning wheels - tightening and loosening things - could place that one bit of force at the right spot at the right time and end in tragedy.

I built my repair stand that mounts on the front wheel dropouts (front wheel removed) and supports under the BB. the only issue i've had while working on bikes is the handle bars are a bit high when working on the levers which i could fix by cutting the stand leg in front a bit shorter but i been too lazy so i just stand on a small stool. 

The best part is it folds flat and hangs on the wall out the way when not in use

Edited June 9, 2022 by madmarc

[guidodg]

6 minutes ago, madmarc said:

In my opinion, bike repair stands are the worst design i've seen from an engineering point ye ye I know its an industry standard but for me clamping on the seat post / dropper post or the frame just doesn't sit well with all the work being done on the bike - spinning wheels - tightening and loosening things - could place that one bit of force at the right spot at the right time and end in tragedy.

I built my repair stand that mounts on the front wheel dropouts (front wheel removed) and supports under the BB. the only issue i've had while working on bikes is the handle bars are a bit high when working on the levers which i could fix by cutting the stand leg in front a bit shorter but i been too lazy so i just stand on a small stool. 

The best part is it folds flat and hangs on the wall out the way when not in use

pictures or it never happened..😃

[MudLark]

30 minutes ago, guidodg said:

on aluminum bikes that is ok..on a carbon frame you are taking a big chance...

Why would that be?

Incidentally I have 5 carbon bikes that I work on quite frequently this way. I clamp them at the point where the bike balances more or less between front and back. Haven't come unstuck.... yet....

[guidodg]

2 minutes ago, MudLark said:

Why would that be?

Incidentally I have 5 carbon bikes that I work on quite frequently this way. I clamp them at the point where the bike balances more or less between front and back. Haven't come unstuck.... yet....

sure....and it may never happen...but the carbon is very thin and never circular where you are clamping and it is not made to withstand a crushing\squeezing  force in that direction...there are plenty of youtube videos explaining this.. 

Edited June 9, 2022 by guidodg

[MudLark]

8 minutes ago, guidodg said:

sure....and it may never happen...but the carbon is very thin and never circular where you are clamping and it is not made to withstand a crushing\squeezing  force in that direction...there are plenty of youtube videos explaining this.. 

Absolutely. Which is why, just like when using a Thule platform rack, one had better not overtighten the clamp. Viewer discretion advised, etc. 🙂 

[MTBRIDER1234]

1 hour ago, MudLark said:

Weird. I only ever clamp a bike by the top tube. I only work on my own bikes though.

I find that a fair number of bikes' toptubes do not fit well in the parktools stand and if you try to clamp them, the bike will move around and be a pain to work on.

Also like giododg said, it is a huge gamble to clamp the toptube of a carbon bike, it only takes one bit of a revolution too much, when you are distracted and you will end up with a cracked frame.

[Quagga]

What do you think about clamping a carbon bike at the seatpost and then hammering out the BB?

Without any other support onto the frame?

 

Would it not put lots of stress on the seatpost and maybe cause horizontal cracks in the carbon seat tube?

 

I have always put the frame on something on the ground and supported it when removing a BB but maybe I have been wasting my time?

[MTBRIDER1234]

6 minutes ago, Quagga said:

What do you think about clamping a carbon bike at the seatpost and then hammering out the BB?

Without any other support onto the frame?

 

Would it not put lots of stress on the seatpost and maybe cause horizontal cracks in the carbon seat tube?

 

I have always put the frame on something on the ground and supported it when removing a BB but maybe I have been wasting my time?

Personally I never would and have never seen a BB be hammered out in the stand. I have always put the frame on a block of wood or similar to support it. Definitely would avoid doing that with a carbon bike, but depending on the frame deisgn, some may be fine and some will break... not a chance you want to take

[Jewbacca]

Surely you 'tap' out a BB with both tires on the floor?

That way no more force is being pushed through any one part of the frame/bike than is when railing corners or hitting flat edges?

In a stand or on a block of wood? yeah nah

[Quagga]

2 minutes ago, MTBRIDER1234 said:

Personally I never would and have never seen a BB be hammered out in the stand. I have always put the frame on a block of wood or similar to support it. Definitely would avoid doing that with a carbon bike, but depending on the frame deisgn, some may be fine and some will break... not a chance you want to take

I saw it being done to a Sworks 

It was only the frame and seatpost in the stand. Was shocked hence my question here,. But also thought maybe it is ok?

 

I always did it the way you describe

[Quagga]

1 minute ago, Jewbacca said:

Surely you 'tap' out a BB with both tires on the floor?

That way no more force is being pushed through any one part of the frame/bike than is when railing corners or hitting flat edges?

In a stand or on a block of wood? yeah nah

I have also used that method, if the frame has wheel on it already 

But once or twice I had a frame without wheels so I put it on the ground/supported

[MTBRIDER1234]

6 minutes ago, Jewbacca said:

Surely you 'tap' out a BB with both tires on the floor?

That way no more force is being pushed through any one part of the frame/bike than is when railing corners or hitting flat edges?

In a stand or on a block of wood? yeah nah

To each their own.

I have worked on and seen enough bikes be worked on to know what works. On a block of wood, there is less force as the frame is being supproted and also you are able to be more precise and accurate as it is more stable.

[MTBRIDER1234]

7 minutes ago, Quagga said:

I saw it being done to a Sworks 

It was only the frame and seatpost in the stand. Was shocked hence my question here,. But also thought maybe it is ok?

 

I always did it the way you describe

Out of interest was it at a bikeshop or the rider doing home maintenance?

Just as I know a few s-works riders who have questionable methods of carrying out maintenance on their bikes...

[Quagga]

1 minute ago, MTBRIDER1234 said:

Out of interest was it at a bikeshop or the rider doing home maintenance?

Just as I know a few s-works riders who have questionable methods of carrying out maintenance on their bikes...

Saw it at Bikeshop, when I was browing around.