I wondered why I had to go get another 15mm of steerer spacers. I have 50mm of spacers in total which looks stupid. My steerer is about 200mm as it is from my 15" Merlin frame and I don't want to cut it as it will make it unusable in most other frames.
Bike Forum
Interesting headset problem (tapered steerer, carbon 456)
-
Posted 1 year ago #
-
I also just checked the geometry table on the on-one site and it states 105mm for the 16" frame. 90mm is for the 14" frame. I think someone has cocked up with the design/manufacture.
Speaking to Steevo yesterday, it turns out the C456 geometry page is mostly wrong. There is no 14in C456 for a start..........
Posted 1 year ago # -
On One - can I have a frame that has the geometry specs you quoted please? Really not happy that I won't be able to fit a tapered fork without a bodge.
To be fair I think 'bodge' is a strong word. It's only a few mm in it and a modified crown race or an external race on the top headset cup will sort it.
I'm actually riding mine as is. There is a small amount of detectable play, but I've got rid of the noise I had with my own mods to the taper ring. I'm quite happy to let O-O work on a solution. These things happen and we all learn, yes? No point in me throwing a wobbler about it.....
Posted 1 year ago # -
Given that the previous short term solution was a +3mm lower crown race a +8mm one begins to sound more like a workaround than a solution, tbh.
Posted 1 year ago # -
Who mentioned +8mm? I don't need that much!
EDIT
We are therefore arranging a series of +3/+5 1.5" Crowns to see which works best... Stevo
I'm hoping he's going to send me one!
EDIT 2
I think I understand now: You're thinking of the 5mm shorter head tube, yes?Posted 1 year ago # -
We are therefore arranging a series of +3/+5 1.5" Crowns to see which works best... Stevo
which was based on a 95mm headtube (again from his post) - if the headtube is only 90mm he'll need to add another 5mm to his crown races won't he?
Posted 1 year ago # -
if the headtube is only 90mm he'll need to add another 5mm to his crown races won't he?
See EDIT 2 above!
But no, 3mm will probably fix mine, and 5mm certainly will.
Although, agreed, he's 5mm out on the head tube length, well either that or it's me that's wrong!
Which is all very odd based on Stevos numbers above too
Posted 1 year ago # -
would it have been enough before you started 'adjusting' things with a file?
Posted 1 year ago # -
Yeah, I think so. What I've done is minimal, there's not much to work with!
Posted 1 year ago # -
Looking back at the pic in your first post it looks like the upper crown race is sitting a good 5mm onto the taper of the steerer, surely as you have suggested a modified top cup with additional spacing to house a external headset is going to be the best solution.
Have you heard anything back from BETD?
Posted 1 year ago # -
IFF the 108mm measurement for the taper is correct then the reason your modifications work is that the top bearing ID is larger than 1 1/8th so your bearing is actually sitting over the taper.
Stating the measurements:
Head tube: 90 mm
Lower stack (inc. crown race): 14 mm
Recess of bearing in upper cup: 6.5mmThis leaves us with 97.5mm (90 + 14 - 6.5)
Fork tapered section: 108 mm
ie there is 9.5 mm deficit - I'd like a few mm on top of that for peace of mind.
But - as the bearing is actually bigger than 1 1/8th then we can steal some height from the bearing depth depending on the split ring that goes into it that Pete modified.
To fix it properly you need to ensure that the split ring is not bottoming out or deforming on the taper. The ring is not the full height of the bearing so you can steal some height from the bearing fitting over the taper but only a couple of mm.
5mm may 'just' sort it but I would like to see 8-10mm to be safe.
Posted 1 year ago # -
Have you heard anything back from BETD?
Not a sausage. O-O are the bset bet methinks.
so your bearing is actually sitting over the taper.
Yep! But not by much, the taper seems to end in the space of the bearing, so the split taper ring in the headset is squased too tight between the bearing and the taper
Whatever the maths say, there's not much in it. Maybe production variances will have na effect between different forks and frames, but I reckon 3mm will fix mine, 5mm for sure.
Posted 1 year ago # -
They'll get it sorted.
One thing they could do to remedy the problem on new frames is make a new upper headtube insert (the bonded in one) that protrudes from the top of the headtube a bit more and is then painted with the rest of the frame.
Would then mean any tapered headset (eg the Hope etc) will still fit.
Edit: other factors are:
1. is the front end as torsionally stiff as it should be if the top tube is lower down?
2. It is still very annoying to have to use a silly amount of spacers unless you want to cut your steerer down an extreme amount. I was meaning to post asking for suggestions on things to use to reduce the mass of visible spacers.
On the plus side the lower top tube gives slightly better standover.
Posted 1 year ago # -
Do fork manufacturers make the steerer tubes themselves or buy them in?
Posted 1 year ago # -
probably made elsewhere but to their specification - hence the proliferation of (and lack of) standards
Posted 1 year ago # -
Would also be worth checking the tapers on carbon steerers before a solution is decided on as they may be even longer.
Posted 1 year ago # -
Sorry to drag up an old thread, thinking about getting the carbon 456 but have a headset Q for the experts. Currently got a standard 1 1/8" hope headset - will I need a new complete headset or is there just the 1.5" part I can buy and still fit "normal" 1 1/8" steerer forks?
Posted 1 year ago # -
I have just built mine up and when i was putting the headset smoothie into the headset, it was that slack i could nearly push it in with my fingers, all i actually had to do was tap it in with a hammer, and i mean tap, havnt rid this one yet so will have to see this weekend
Posted 1 year ago # -
UPDATE:
Stevo from On One has sent me 2 thicker crown races, +3mm and + 5mm, as he said he would. They're chunky wee things:
IMG_1078 by PeterPoddy, on FlickrBike with standard crown race:
IMG_1075 by PeterPoddy, on FlickrBike with +3mm crown race:
IMG_1079 by PeterPoddy, on FlickrI've just fitted the +3mm one and it fits fine. The headset has tightened down fine and there's no play at all in a 'garage test'. Sadly it'll be at least a week before I get to take it for a ride, but it looks promising and I'll report back again.
Posted 1 year ago # -
UPDATE
Managed to get a ride in yesterday and the +3mm crown race seems to have fixed the problem.
Thanks to Stevo at On One for the help!
Posted 1 year ago # -
Great stuff. What happens if you want to upgrade to your usual CK headset?
Posted 1 year ago # -
CK won't fit Dez. Well not my usual £45 used ones at least. Do they even do tapered headsets? I don't think they do semi integrated either, like the top race....
Posted 1 year ago # -
Bit of a bump in case anyone's is interested in the new crown races
Posted 1 year ago # -
I notice that Hope list a +3mm crown race for their version of this headset - probably more for crown/downtube clearance issues but might solve this problem too.
Posted 1 year ago # -
Pete, is there an O ring on the bottom of the lower cup to fit into the outer groove on the crown race?
Posted 1 year ago # -
Andy, I can't say I've noticed one to be honest. There certainly isn't a separate one, put it that way.... I guess there might be one fitted somewhere, but sorry, I'm not taking the forks off to have a look!
Posted 1 year ago # -
Just got my external bearing upper cup from On One (thanks guys).
I now realise the groove in the On One crown race is a labyrinthine seal with a lip on the bottom of the lower cup as they have this set up on the top cup instead of a rubber seal or o-ring.
The new upper cup will easily sort the problem so just have to knock out the upper cup now and fit it. It has a massive 1.5" bearing which makes me wonder if a 1.5" straight steerer could be used with a different upper cap and compression ring (what is it called again?). I guess this will let them use tapered or 1.5" steerers on their new steel frames with 44mm ID head tubes.
Posted 11 months ago # -
Andy the simple answer is Yes
If you put a top and bottom external cupped head set onto a 44mm id headset a 1.5 inch strait steerer can be used.
Nuke proof make head sets like this currently with extended inner lips but i was lead to believe by brant they will be releasing standard length headsets similar to the cane creek ones in the not to distant future.
back to the tread, does this now mean On One have now come up with a second solution to the issue with a re-worked top hedset section or the extended lower crown race?
Posted 11 months ago #
Reply
You must log in to post.
