Convert 1" steerer to use with 1'1/8 headset

[retrojohm65]

I ve got some really nice unknown MTB forks I think theyre possibly reynolds 531
and want to use them on my rocky mountain but the steerer tube being more modern is obviously larger, has anyone had success with some kind of homemade conversion,
for the lower i don't see a problem using the crown race with some kind of shim, any ideas would be appreciated
john

 

[jamabikes]

i would say your best bet is to either get the head tube shimmed to one inch or i think chris king do custom headsets to run 1" forks in 1"1/8th head tubes. hope may do them too.

 

[retrojohm65]

sounds pricey! but many thanks

 

[bm0p700f]

Given the cost of new steel forks in 1 1/8" size I do not see the point of faffing trying to convert.

 

[We_are_Stevo]

Now this is going to be a glaring admission of my own ignorance on this matter, but are the headtubes themselves actually a different size??

Is it not just a case of fitting different headsets for different size steerers??

I ask because, more than once, I have removed a 1" threaded fork/headset and fitted a 1 /18" aheadset/threadless fork to the same frame??

 

[retrojohm65]

in anwer to.... "I do not see the point of faffing trying to convert" a few reasons why,
1 just for the challenge.
2 was looking at something like the project 2's, bontrager switchblade, gusset trials forks etc, and take your point, but ultimately
3 the retro reynolds 531 forks really have a nice look about them, the bike is a 2003 rocky mountain elevation with rockshox dirt at the moment,and as will be using purely on the road, all fat tyres and rockshox just isn't necessary
you might be right tho, after all that mucking about the geometry might just be completely shite!

your right you can put a 1 1/8th steerer in place of a 1 inch front ive done it as well and it does work, not really sure how? but the other way round it doesn't and rocks about like a "prick in a top hat" the tube is a different size so can't just swap the cups over. more experimentation needed at my end i wonder if the bearings are a factor?

 

[We_are_Stevo]

No, I've definitely drifted out a 1" threaded headset and replaced it with a 1 1/8" AheadSet...

 

[velomaniac]

You get 1&1/8th" - 1" headset shims fitted to the frames headtube.I believe these are available. Then using a 1" Headset you fit the 1" steered forks.

Your making it complex if you insist on a 1&1/8th" headset as you need to shim the steerer which is not an idea I think anyone has embraced as a useful one :?

 

[MADJEZ]

Halfords, £12, sorted.

http://www.halfords.com/webapp/wcs/..._productId_568679_langId_-1_categoryId_230508

 

[MikeD]

Now this is going to be a glaring admission of my own ignorance on this matter, but are the headtubes themselves actually a different size??

Yes. 1in is about 30mm ID, 1-1/8in is about 34mm (can't remember exact numbers off the top of my head).

Is it not just a case of fitting different headsets for different size steerers??

No.

I ask because, more than once, I have removed a 1" threaded fork/headset and fitted a 1 /18" aheadset/threadless fork to the same frame??

With all due respect, no you haven't Suspect that you may be getting confused by the markings on quill stems. A quill stem to go in a 1 1/8in threaded steerer will have a 1in diameter and be labelled 25.4mm. A quill stem to go in a 1in threaded steerer will have a 7/8in diameter (22.2mm).

The easiest way is to get some headset reducers, which are just shims to let you put 1in cups in a 1-1/8in frame.