Quest Diatech aheadset replacement

Cruzbiker

Active Member
My Quest has the conical Diatech aheadset. I do not like it. I have the new fork without suspension and built a pair of 406 wheels for travelling. When I pack it in the suitcase I have to remove the fork, and setting up the Diatech is not easy.

Is it possible to replace the Diatech by another aheadset? I have already a star nut in my fork and an extension for the aheadset screw.

Do I have to change the cups in the frame, or the cups are kind of “standard”? I assume I would have to change the crown race too. The top race has to be changed; this is where the Diatech is different from other aheadsets.

Making it short, what do I need to change to replace the Diatech aheadset for a regular one with star nut in the fork? Any suggestions on aheadset brands/model? Has anyone replaced the Quest Diatech?
 

Cruzbiker

Active Member
Kudos to your mod!
I already got the longer star nut bolt. But as I said, I travel a lot and have to remove the fork when packing the Quest. It might be just me, but I do not like the Diatech with that centering ring and adjusting clamp. It is always difficult to get the right adjustment. A common headset, adjusted only with the star nut bolt seems to be easier to adjust.
 

Robert Holler

Administrator
Staff member
I am awaiting parts for the fix/upgrade to this. The key has been finding something that has the same slim profile.
 

Emeljay

WiskersBlowinInTheWind
Cruzbiker, what I was implying is that one doesn't have to replace headset parts, just use a star nut/bolt (needs to be a looong bolt when using the long stock fork tube extender) to do the tensioning.
 
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DavidJL

Well-Known Member
The long bolt doesn't need to stay with the bike, just enough for the preloading and tightening of the stem. A rod with just enough threads could be used for the bolt.
 

Emeljay

WiskersBlowinInTheWind
David, I have used several methods of preloading the the stem on my Quest 559 (none worked consistently well), but never thought to use threaded rods of which I have and are even now staring into my face! Kudos for bringing that idea to this forum!

My problem, and others who have snapped the clamp bolt using too much pressure (reported on this forum), is that to consistently be able to get and retain the clamp adjustment is difficult at best which if not tight enough loosens on riding and if tightened too much may snap the bolt or damage the clamp which I have done (thank you Robert H for getting me a clamp so fast to get my Q going again!).

That was one of my motivators for me to mod my steering on my X100 which I now ride daily and am enjoying not having to check/adjust the headset tension nor worry about snapped clamp bolts.

All said and done I appreciate all who participate in this forum in the exchange of ideas and discoveries for the benefit of all. Kudos to all!!!! :)
 

DavidJL

Well-Known Member
On my QX100, I modified the BI-3 headset by drilling and tapping to 4 mm the top piece. I used 2 4-mm threaded cap screws to hold the adjustment, and then pushed the boom clamp on top of the cap screws to insure that the top assembly can't slide upwards and loosen the headset. That one little puny set screw just wasn't getting it, and it was apparently not even metric because it took a 1-16 inch Allen key. I did use a drill press to drill the holes and then used the drill press to insure the tap was going in squarely, not actually powering the press, but turning it by hand. The drawback about using a temporary long threaded rod is that you couldn't adjust the headset on the road.
 

Cruzbiker

Active Member
Mr Google and Mrs Internet told me everything about headsets and how to replace them. Now it is just a matter of choosing one. I have been looking at FSA and CK models. Any suggestion?

Robert H, which one did you choose for the upgrade?
 

Robert Holler

Administrator
Staff member
Here are the parts for people who might be able to source them. For me - having to order through a supplier this can be a real hassle when things are out of stock (which is often in the US)

http://problemsolversbike.com/products/micro_adjustable_headset_spacer

http://problemsolversbike.com/products/locking_headset_spacers

Use the adjuster first - make it as thin as possible - then the locking spacer. Lock the latter down after doing a "pre-set" of the headset and then dial in the adjuster. Lock that into place and you are good to go. This was the setup I used to build the V2K's last year.

Robert
 

skipB

Member
I am not as mechanically inclined as some in the cruzbike family . I have the problem solver parts . as per your instructions on the forum .I am just not clear on how the stack should look ,I think from top to bottom< the pivot clamp, then the problem solver micro adjustable clamp, then the problem solver locking headset spacer ,and finally at the bottom the existing headset set ring .
does that sound right
 

Cruzbiker

Active Member
I bought a FSA, i think the Orbit X model with sealed conical bearings.
Took the bike to my LBS and in 1/2 an hour they replaced the Diatech (changed the fork race and replaced the frame cups).
It is much easier to set up now than with the Diatech. I also bought a problem solver locking headset spacer, not the adjustable one. I use the star nut and a long bolt to adjust it.
I think it might be because the bearings are conical, so when you adjust tension they move in place by themselves. I am very glad I changed it.
 
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