tapered head tubes

dominicg

Hi,
Think I posted this on the wrong forum.

Hi,
Does anyone know if I can use a "straight" 1 1/8 steerer in a tapered 1 1/8 to 1 1/2 head tube e.g. Ribble Gran Fondo? Is there an adapter or something that could be used. I know mtbs are able to get round this but I'm not sure about road bikes.

Thanks,

Dominic

smidsy

Steerer is straight it's the headset that alters.

dominicg

thanks smidsy but I still don't get it. Ribble have 2 forks: one for each incarnation of their GF (and neither available to buy BTW) so presumably there is some difference. Are you saying that I just have to get a 11/8 to 11/2 headset? That would be handy! thanks for posting on "buying advce"
cheers

smidsy

I do not know the Ribble GF specifically but it is common for manufacturers to have different rake forks as the frame sizes increase.

Is that the difference between them?

Yes you need a 1/1'18 1/1'12 headset.

ellj22

Is it an integrated or semi integrated headset? In other words does a cartridge bearing drop straight in the frame (integrated) or is a cup pressed into the frame and a bearing dropped into that (semi integrated)?

Just checked, doesn't the Gran Fondo have a straight 1 1/8 head tube?

dominicg

Thanks, yes you're right at least for the newest version but the 2012 model is meant to be tapered. ITS hidden?? That mean anything?
cheers D

smidsy

Another point

The forks will be different for the 1/12 as the head tube obviously flares out (bugger a the bottom) so the profile on the shoulders of the forks will be wider so that it lines in with the head tube (providing a nice smooth join).

So if Ribble have two listed that may be why.

ellj22

ITS will be the headset standard I believe and will define the exact dimensions of the bearing (ID,OD height and angle of bearing). Pretty sure it's a fully integrated headset. Hidden basically means the headset type is either integrated or semi integrated as you cannot see them (or hardly see them once fitted). If it is fully integrated you will not be able to get a shim to step it down to suit a straight fork but cane creek do offer step down integrated headset that MAY suit but best thing to do is ask Ribble, or measure the frame up and check against bearing dimensions.

http://www.canecreek.com/products/headsets/forty

One of the conversion headset lowers from this link may suit and if so then you should be able to order it through any Cane Creek dealership.

What is it you are trying to achieve? are you trying to fit a current 1 1/8 fork to a new 1 1/8 to 1 1/2 taper frame?

dominicg

Thanks both of you. Yes that's right. I have ordered a frame from said Ribble's clearance section but it comes without forks. In fact you can't buy the forks seaparately. I have a perfectly good set of forks already (11/8 straight) and I thought the obvious thing to do was to switch it to the new frame etc.
Cheers

smidsy

I know they say you can't buy them alone, but they must be available for spares/replacement e.g crash damage.

What do they expect you to put on there if they will not sell you some??

The GF forks are sculpted to match the GF frame, anything else is going to be a best guess.

ellj22

Once you receive the frame get some accurate dimensions of the head tube (to the nearest 0.1mm) and from there you may well be able to find a conversion headset to fit (like the cane creek). However It will be unattractive stepping down from a 1 1/2 lower headset bearing to a 1 1/8 fork due to the small crown size.

I would be surprised if one of Ribble's other 1 1/8 to 1 1/2 forks doesn't fit and suit well.

dominicg

Thank you both for advice. I had an email from Ribble yesterday saying that they had found some ex-display GF forks cut at 240mm that I could have for forty quid!! That's just the right length for me so happy days! Glad I don't have to get into all that reduction headset business after all. Thanks again

smidsy

This is my Basso prior to being built up.



You can clearly see the uncut steerer in the tapered head tube. The shoulders of the forks are designed to blend with the frame. just to give you a better idea

Obviously this is before the headset is fitted etc.