I’ve used one of these before on a Specialized kenevo e bike with a very short steerer on some rockshox boxxers. I was apprehensive at the start about it. When I fitted it I put a good smearing of jb weld down the steerer and on the extender then tightened it up and left it for 24 hours. I never had an issue with it.
I know a few people who have these including myself & when first installed give it a good slathering in JB Weld & youre golden. After all ..... You want it to be permanent. 😉👍🏼
@@TheBigwesb yeah. I did think about using some sort of bond, something like a 2 pack epoxy came to mind. But for the video, I was trying to demonstrate it as it was purchased. I’ve heard of others bonding it with good results.
@@retfurb yeah the one I have isn't like yours that has the 3 knurled sections held on with the bands. My one has 1 knurled tube with a slice down the side to expand & does seem to hold a lot better than the 3 piece lower section & a lot easier to tighten up square unlike some of the others I have seen that always tend to tighten up off the centre line. Great video though & bravo for highlighting the dangers of what could go wrong with poor fitment & maintenance. 👍🏼
This is a poorly designed extension. Split ring, soft material, too basic. Better design would use two sections vertically, knurled, sliced diagonally (60 degrees?). Essentially, a knurled sleeve, mid cut diagonal at 60 degrees. The bottom piece threaded for the stem bolt. When tightening the bolt, two sections pull to touch and slide offset at the diagonal cut and push equally internally against the internal. The top piece slightly larger bore to allow offset when tightening. I guess I should make one and test it.
Try using some carbon paste to give the knurled sections additional grip against the ID if the existing steerer tube. That removed any vertical play i experienced when experimenting with one of these. Hope that helps
It does seem like a good idea to have a little bit of the stem clamping upon both the extender and the steer tube itself. I would not trust the star nut by itself to hold the extender onto the steer tube, seeing as though the star nut is really not supposed to have such forces applied to it. Is this a fair assumption? As far as it coming loose, I wonder if for whatever reason it requires more preload on the top cap screw that normal. Along with that maybe it needs more torque on the stem bolts... and even carbon paste.
@@icantgivecredit871 I tried to have it clamped on both, but it was no good. I also tried tighter and looser torques for the various securing parts. Still no good.
Interesting. I didn't think the knurling on the extension would have enough grip, but I thought it would have had more rotational play rather than up and down play.
I’ve used one of these before on a Specialized kenevo e bike with a very short steerer on some rockshox boxxers. I was apprehensive at the start about it. When I fitted it I put a good smearing of jb weld down the steerer and on the extender then tightened it up and left it for 24 hours. I never had an issue with it.
@@MrLeong1989 yeah, I think that’s the general opinion from others who have used it.
Using an additional bond, along with the mechanical fixing.
👍🏻
I know a few people who have these including myself & when first installed give it a good slathering in JB Weld & youre golden. After all ..... You want it to be permanent. 😉👍🏼
@@TheBigwesb yeah. I did think about using some sort of bond, something like a 2 pack epoxy came to mind.
But for the video, I was trying to demonstrate it as it was purchased.
I’ve heard of others bonding it with good results.
@@retfurb yeah the one I have isn't like yours that has the 3 knurled sections held on with the bands. My one has 1 knurled tube with a slice down the side to expand & does seem to hold a lot better than the 3 piece lower section & a lot easier to tighten up square unlike some of the others I have seen that always tend to tighten up off the centre line. Great video though & bravo for highlighting the dangers of what could go wrong with poor fitment & maintenance. 👍🏼
@@TheBigwesb thank you, it’s appreciated. 🙂
This is a poorly designed extension. Split ring, soft material, too basic.
Better design would use two sections vertically, knurled, sliced diagonally (60 degrees?).
Essentially, a knurled sleeve, mid cut diagonal at 60 degrees.
The bottom piece threaded for the stem bolt.
When tightening the bolt, two sections pull to touch and slide offset at the diagonal cut and push equally internally against the internal.
The top piece slightly larger bore to allow offset when tightening.
I guess I should make one and test it.
@@clarkleakins879 you mean same as the old style swans neck?...... Yeah it's already been designed has that 😉🤭👍🏼
Try using some carbon paste to give the knurled sections additional grip against the ID if the existing steerer tube. That removed any vertical play i experienced when experimenting with one of these. Hope that helps
@@Conor_Ryan thanks for the tip.
Interesting option. I completely rebuilt and repainted a fork and then had too short of a steer tube... Donated it. LOL
It is a good idea, definitely. It may just be that the one I had could not grip enough in the tube.
It does seem like a good idea to have a little bit of the stem clamping upon both the extender and the steer tube itself. I would not trust the star nut by itself to hold the extender onto the steer tube, seeing as though the star nut is really not supposed to have such forces applied to it. Is this a fair assumption? As far as it coming loose, I wonder if for whatever reason it requires more preload on the top cap screw that normal. Along with that maybe it needs more torque on the stem bolts... and even carbon paste.
@@icantgivecredit871 I tried to have it clamped on both, but it was no good.
I also tried tighter and looser torques for the various securing parts. Still no good.
이 영상처럼 작업하면 핸들이 충격에 돌아가고 그 유격으로인해 목이 부러지는 위험을 초래합니다.그러나 jb weld같은 에폭시 본드를 compress 3면에 충분히 바르고 장착하면 안전합니다.단 고착으로 앞으로 더이상의 높이 수정은 어렵습니다.
Exactly, This is what I was demonstrating. It does not hold sufficiently enough.
Is it really stuck if it's, its good. I would try
Interesting. I didn't think the knurling on the extension would have enough grip, but I thought it would have had more rotational play rather than up and down play.
I was optimistic at the start and it initially seemed ok. I wonder if it would have been better, if it was made like the older threaded headset clamp.
You put way too much torque at the cap bolt (as you mentioned)!
2-3 nm is enough. No wonder you pulled out the extension.
@@toddio148 I tried it with a light amount of torque, then increased and then as tight as I could.
All ended up in the same result.