Jump to content

Brother stem clicking noise + bar slipping (same clamp as the Try All


niconj

Recommended Posts

Hello,

so I've got a Brother CNC stem which I bough used in this forum. I use it with a Tensile 99 bar and can't get it to be quiet + the bar slips. Here's how I've mounted it:

- cleaned the clamping area and put some dynamics carbon paste on it (w/o it would slip even with higher Nm).

- changed the bolts for some with a washer and greased the threads plus the head of the screws

- clamped it to 5Nm

Today I went out riding and it still makes this clicking noise and as I did a sidehop it made a louder click and the bar slipped a tiny bit. The bar is almost new and hasn't done this noise w/ another stem.

I really like the geo of this stem but the clicking/slipping drives me nuts.

Since many of you guys are using the TryAll stem, which uses the same clamping mechanism, I was wondering if any of you had these problems and if so, how you got rid of them.

Thanx,

Nico.

Link to comment
Share on other sites

Tighten the bolts more. Think of 5Nm more as a guide- I sure as hell have always tightened stem bolts to more than 5Nm...

I don't think, that this would solve the clicking issue and as stated at Tarty the "maximum bolt torque [is] 6Nm, over-tightening can crack the clamp".

Link to comment
Share on other sites

Used to have a clicky/ticky with Tt bars in a Tt stem, made the noise every time you'd shift weight forwards or backwards...clean everything and it would go away for 20min or so and start again, rubbing the ano off the contact area of the stem with some fine grit wet and dry eventually sorted mine.

When my bars slipped ages ago they made a horrid noise like they'd broke (tiny scuff was all the damage) 5nm isn't very tight at all I certainly do mine up more than that, tighten it until it feels right (what I do and its been a long while since I snapped/rounded/threaded any bolts). If your bars are slipping first thing I'd try is tightening a bit more (1/4 turn at a time) and see how it fairs with that, disclaimers are there for apes that swing on bolts...

Link to comment
Share on other sites

Yeah I kinda know about the disclaimers but I haven't had to tighten any stem more than 4Nm in my life especially when using carbon paste. I'm not worried about stripping the bolts but rather braking my bars. I wonder if it's a problem of the bars being very shiny (I mean the finish of the bars, don't know the English word for it).

With "grit" you mean sandpaper? What number would you recommend? 400? 800?

Also, I was thinking of mounting TryAll Carbon bars but am afraid that these wouldn't stand the clamping mechanism of the brother stem.

Link to comment
Share on other sites

Yeah I get the shiny, gloss if you want to be anal about it haha. I imagined it was down to tiny bits of the ano 'wearing' in the areas in contact and the sound tiny bits of it being crushed then transmitted through parts loaded with conpession/tension giving that annoying tick sound. I doubt you could tighten an m5 bolt enough to cause alu bars to fail without it snapping/stripping.

I used 1200 just as I had it to hand, anything finer than 600 will do the job.

I was dubious of the design of the k2 when I first saw that (especially for carbons) but I'm sure plenty of people have and had no issues of compatibility. Never had problems with the carbons I had, went for the tighten it 'till you pull a stupid face approach albeit in a different stem and they served me well.

Link to comment
Share on other sites

Hm... I don't know about the anodizing part though. I can't imagine that this is really causing the issue. I've got some 800 here but will wait until maybe some other guys have responded. I'm not sure but I think that an alu/alu connection is prone to make some noise under great amount of force.

Link to comment
Share on other sites

until I sanded the finish down.

I think it doesn't have to do with the anodizing but rather the rougher surface created when sanding it. I'll do it then and will keep you guys updated. Only thing I dunno is how to sand the inner side of the shims. Can't really reach it I mean...

Link to comment
Share on other sites

Well, I sanded off the anodizing but it's still making that noise and this only 15mins. into the ride. I am kinda annoyed as I have cut the steerer in that stupid angle and now I can't fit any 4bolt clamping stem anymore. Are there any 150x30 that have a sloping top but a 4 bolt clamp?

edit: I haven't been able to move the bars but haven't tried much either.

Edited by niconj
Link to comment
Share on other sites

ZHI and a few others do. I'd say try another method with your stem though

Like what? I don't really want to grease the clamping area.

Mine did it a lot on my new bike, I ended up using a nut and bolt through the bar clamp and the problem no longer exists.

I don't understand. Instead of using a screw only, you fixed it on the downside with a nut as well?

Edited by niconj
Link to comment
Share on other sites

Yup. Taken this pic just now for you hot stuff.

Thanks! Only you don't have the stem I'm talking about. Still, it might be my last resort.

I just figured out that this time, it wasn't the clamp at the bar but the one at the steerer making noise. As I put all my weight onto the bar and then just took the shaft into my hand* and pulled it up it made a loud click. So it couldn't possibly be the clamps at the bar.

I took the bolts off the stem, greased them, put a light coat of grease onto the steerer (here I'm not really afraid as there will hardly be any slipping upwards of the entire stem) and put everything together with the bolts being tightened at 6.5Nm. The clicking noise has disappeared for now but it wouldn't be the first time that it came back again after a short session. For now I'm positive though.

*Please don't quote this. :D

Edited by niconj
Link to comment
Share on other sites

Are you absolutely sure its the bar clamp? What forks are you running?

Edit: Missed your above post. Was going to say, I had a constant creek on the front end with a practically brand new set up until I changed the shit Echo forks.

Edited by wilf
Link to comment
Share on other sites

Are you absolutely sure its the bar clamp? What forks are you running?

Edit: Missed your above post. Was going to say, I had a constant creek on the front end with a practically brand new set up until I changed the shit Echo forks.

I do have Echo forks but it only started clicking, wenn I swapped the stem. Before that I didn't have any noise.

I was wondering if a carbon bar would get rid of the noise (if it comes back) as there isn't metal on metal.

Edited by niconj
Link to comment
Share on other sites

Today I've figured out that it's not the bar that is actually slipping but the clamps that move up and down. I made marks on the stem and while the bar stayed in it's position(relative to the clamps), the clamps moved up and down depending on whether I was leaning hard on the bar or pulling it. I really don't know how to counteract this as I don't want to tighten the bolts further. I have already reached more than the max torque.

Shouldn't have bought a used stem...

Edited by niconj
Link to comment
Share on other sites

Join the conversation

You can post now and register later. If you have an account, sign in now to post with your account.

Guest
Reply to this topic...

×   Pasted as rich text.   Paste as plain text instead

  Only 75 emoji are allowed.

×   Your link has been automatically embedded.   Display as a link instead

×   Your previous content has been restored.   Clear editor

×   You cannot paste images directly. Upload or insert images from URL.

Loading...
  • Recently Browsing   0 members

    • No registered users viewing this page.
×
×
  • Create New...