I have a 2011 Marin Kentfield with a threaded headset that I want to change to threadless. I'm aware that I would need a new fork, which I would like to upgrade anyways. I assume I'd also need a stem and headset as well. Is there anything else?

Is the work/labor to do this conversion easy as switching out the parts? or is there any special mechanical work that I would need to have professionally done?

fork, star-fangled nut to go in fork steerer.
headset, stem, and sufficient spacers to span the distance
between top of headset and bottom of stem..

unless you want to use whole length of steerer tube for an upright riding posture

then the steerer tube has to be cut off ...
but if you buy extra spacers you can procrastinate the cutting,
as the headset is adjusted by the bolt into the star-nut
as it works just as well pushing down on a spacer above the stem,
as it will with the stem on top,
and the spacers all below the stem..

NB; the stem gripping the steerer tube is what holds the headset adjustment.
you loosen those bolts to change the adjustment,

I stacked 2 stems on my trekking bike set-up, one holds the handlebar bag mount.

Headset installs are best left to the pros.
I'd be happy to talk you out of this upgrade if you're open to the idea.

Will the 1-1/8 steerer tube fit in the headtube of a 1" frame ?

No., because the headset race fitting, takes up room inside the head tube.

Yes leave this to the pro or atleast a very experinced kitchen table mechanic.

also if the bike is a 2011 wouldn't still be under the shops 1 year maint warranty?

Why are you upgrading the fork? Suspension? I am not sure of the rest of the bike but if it has a 1" steerer and a quill stem it is likely not up to serious mountain biking.



OH you also need some tools... 32mm headset wrench to remove the old fork. I tool for removing the bearing races ( aka 'cups' ) from the frame, a headset press to install the new cups, a crown race setter to install the race on the new fork, and a nut setter to seat the starfangled nut in the steerer.

In all honesty i'd outline initially why exactly it is you want to 'upgrade' the bike to a threadless fork first. In all honesty it's probably way to big an investment for minor gains.

This is a $400 bike. What do you expect to gain by going threadless? Also, the specs say it is a 1 1/8" threaded fork on there now. Don't know where you got the 1" (unless from the quill stem).

A confusing question. Do you want to do this just to change the type of stem the bike uses, or do you for some reason feel you actually need a threadless type of headset and fork (I can't imagine any reason for that, but I'm curious if you have one).

IF (big IF, since I don't know), all you want to do is be able to use a threadless type of stem, then all you need to do is remove the current stem and replace it with one of these:

https://www.nashbar.com/bikes/Product...0052_175545_-1___

There's no functional reason why I want to switch, I just think that the threaded headset looks cheap. I know it's a cheap bike compared to other name brand bicycles, and I agree that it's not worth spending $200+ when the whole bike was only $400. I think I'm going with Camilo's suggestion and just use a threaded stem adapter. I didn't know those even existed so thanks Camilo!

Personally, I think a nice quill stem looks far cleaner than a threaded to threadless adapter with threadless stem and you'll still have the threaded headset sitting below it but it's your bike and your $$.