[GTIgor]

Bought it from CRC. Was really impressed with its look and weight/stiffness, but...

At first rides my hadlebar slipped and rotated despite prertty strong tightening - i was surprised but managed to tight it properly. But was concerned if the bar will hold such a pressure... It was on local flat and easy trails.

Then I went to India and then the real problems appeared - in super rocky terrain the stem slipped on the steer tube! I almost crashed severely... It was scary
I kept trying to increase tightening force littly by little but it kept slipping
It all ended up with a broken threads... Had to put a 90mm stem from rent bike from our guides (Thank you Michael and Rakesh!!!)

Did anyone had prioblems with sunline stems?I have a RS Pike (aluminium steer tube) and Truvativ Team handebar.

What really gets me mad - is that Sunline just ignores my mail...

 

[amishmatt]

I had a Sunline DH stem (1.5") and had no issues, but yours is not the first story I've read about Sunline AM stems slipping.

Besides the obvious, making sure the stem/steerer interface is clean and grease free, maybe try contacting CRC for a refund if Sunline is not helping.

 

[Bicyclist]

No issues on mine, rode it at Deer Valley among other DH trails, I had the 65mm version.

Try tightening in an alternating pattern making sure you're getting equal clamping on the faceplate, cleaning everything, and making sure you have enough steerer tube and stem contact (i.e. the steerer is long enough/has the proper amount of spacers).

 

[ultraNoob]

I've never come across any problems with my sunline stems. But I have run across that problem with other stems and it ended up being the bolts. It sounds like your original bolts were stretched. Signs of over tightening or weak bolts is a narrower neck (just past the bolt head) when compared to the middle or tip of the threaded portion of the bolt.

Are the threads in the stem stripped now?