First time fitting Forks

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Scudders
Posts: 14
Joined: 19 Aug 2020, 7:59pm

First time fitting Forks

Post by Scudders »

This is my first attempt at assembling a bike from all of its component parts and have come to a point of uncertainty. Installing the forks I'm not certain I've got these things in the right order. Would appreciate if anybody with the know how could advise.

Bottom
Image
images here https://1drv.ms/u/s!AmE3C-rF9fUUheF9DiF ... Q?e=S8lNig

Top
Image
https://1drv.ms/u/s!AmE3C-rF9fUUheF8JSH ... A?e=gmfABg

Cheeeeeers
Last edited by Scudders on 20 Aug 2020, 2:05pm, edited 1 time in total.
DevonDamo
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Joined: 24 May 2011, 1:42am

Re: First time fitting Folks

Post by DevonDamo »

Scudders wrote:Would appreciate if anybody with the know how could advise.


It's really difficult to tell from those two photos because, for example, in the 'bottom' photo, I'm not sure which bits are permanent parts of the fork and which bits you've slid onto it yourself. If you want a more definitive answer, the following two photos would be more useful:

1. All the removable components laid out on a table along with the (now-empty) fork steerer.

2. All the removable components slotted onto the fork steerer in your suggested order, with a bit of tape wrapped round to show where the frame would be.

However, one thing is jumping out at me from that photo because I've recently rebuilt a headset and I think I've got the same bits as you. In your 'bottom' photo, you've got a single silver ring to the left of your bearing, whereas in your 'top' photo, you've got a similar black ring to the right of your bearing. I think you've got those two swapped around. I think the silver one is the 'compression ring' as it's got a straight conical section which helps it do its job of sliding into the conical indentation in the bearing and jamming it onto the steerer so it doesn't rattle around. The black ring does the same job on the bottom, but it doesn't need to be adjusted, hence it having a concave conical section, which will only just locate the bearing - not jam it.

(Edit: just watched the following video and it seems that the thin washer shown rightmost on your 'top' photo is a sealing ring which goes on top of your compression ring, so you've got that in the right place. Check out the video though:)

https://www.youtube.com/watch?v=yUVelSrCFjw
fatboy
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Joined: 5 Jan 2007, 1:32pm
Location: North Hertfordshire

Re: First time fitting Folks

Post by fatboy »

Surely the leftmost black bit is the wrong way round (bottom photo)
"Marriage is a wonderful invention; but then again so is the bicycle puncture repair kit." - Billy Connolly
DevonDamo
Posts: 1039
Joined: 24 May 2011, 1:42am

Re: First time fitting Folks

Post by DevonDamo »

fatboy wrote:Surely the leftmost black bit is the wrong way round (bottom photo)


It looked wrong to me too, but I wanted to be sure that it wasn't some weird platform thing that had been built into the base of the fork steerer - hence asking for photos of all the components removed.

However, now you've pointed it out, I reckon I've sussed it. Working from left to right from the fork crown, the components slotted onto the steerer are as follows:
('bottom' photo)
1. Spacer(s).
2. Bottom bearing race.
3. Compression ring.
4. Bottom bearing.
('top' photo)
5. Top bearing,
6. Top cover.
7. Sealing washer.

The order they should be on, working from left to right, is:
2 (as fatboy says: turned the other way up.)
4
(frame tube)
5
3 (turned the other way up)
7
6 (turned the other way up)
1
gregoryoftours
Posts: 2234
Joined: 22 May 2011, 7:14pm

Re: First time fitting Folks

Post by gregoryoftours »

The headset needs to be assembled as follows:

IMG_20200819_215120.jpg

IMG_20200819_215339.jpg

Part 1- this is the crown race. Flip this 180° and it needs to sit around the stepped shoulder it is currently sat on top of, with the bevel facing upwards. If it's a split collar it will just push down around the shoulder on the fork. If it's not a split collar it will need installing by tapping it down carefully into place with a piece of pipe of the correct internal diameter, or using a proper headset crown race installation tool.

Remove part 6 for the time being - it belongs in the top half of the headset.

Due to the large internal diameter of the plastic ring (labelled seal ring) I suspect that it's a basic seal designed to rest on the ledge surrounding the upward facing bevel of part 1. If this binds when the headset is put together it probably belongs somewhere else.

Part 2 - This and part 5 are the cartridge bearings. If the markings are the same on both then they are interchangeable. If not you need to find out which is the upper bearing and which is meant to be the lower and install accordingly. If they are both the same then this fits as it currently is between the upward facing bevel of part 1 and the inside the lower headset cup 3. As it is now part 2 is the correct way up.

Part 5 - the upper bearing sits as it is into the upper cup 4. It's the right way up already.

Part 6 - compression ring. Install this split ring, bevel facing down, onto bearing 5. It should wedge into the internal bevel of the bearing.

Part 7 - bearing cover/dust cap. The radius on this can be a little confusing, it faces up and is just like that to look neater meeting the steerer spacers that fit above it, it's not any kind of a bearing race or cone. Flip this part over so that the flat underside sits on the flat top of part 6. The rubber skirt faces down, stopping water/dust getting in. There is a small possibility that if the plastic ring mentioned earlier causes the headset to bind it may instead belong around the outside of part 6 and under the rubber skirt of 7, but I don't think that is the case.

Then your steerer spacers and/or stem stack on top of part 7 as usual.
Last edited by gregoryoftours on 20 Aug 2020, 8:02am, edited 6 times in total.
David9694
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Joined: 10 Feb 2018, 8:42am

Re: First time fitting Folks

Post by David9694 »

https://branfordbike.com/headsets

quite a Useful page here - you’re using a Conventional Threadless Headset and you’ve got cartridge bearings, rather than the ball races shown. The upper “pressed frame race” is pictured the ‘wrong’ way up.

The first item to go on over the steerer is the crown race - this is usually a very tight fit and needs to be hammered into place (and removed) ideally with the appropriate tool. The middle component in your top picture looks like it to me. The cartridge bearing will fill the space between the inside of the lower cup (already installed - by Mr Genesis?) and the profile of the crown race. At the top, the cartridge sits in the “frame race”. I’d expect the lettering on the cartridge bearing to be the right way up when set correctly.

That’s as much as I can say with any certainty - more significant will be that if you’ve got everything in the right order you will be able to feel it running smooth and solid and when you eventually pull it all together there won’t be any play in the bearing.

You’ve presumably Yet got to set the star nut? Another task that really wants to be done with a dedicated tool to get it right.
Spa Audax Ti Ultegra; Genesis Equilibrium 853; Raleigh Record Ace 1983; “Raleigh Competition”, “Raleigh Gran Sport 1982”; “Allegro Special”, Bob Jackson tourer, Ridley alu step-through with Swytch front wheel; gravel bike from an MB Dronfield 531 frame.
gregoryoftours
Posts: 2234
Joined: 22 May 2011, 7:14pm

Re: First time fitting Folks

Post by gregoryoftours »

If your fork has an uncut steerer you may have to install a star nut in the fork once you've decided how high you want your stem/bars to sit and how many spacers under them, and once you've cut off excess steerer length if you decide you want to do this. Watch YouTube videos about fitting a new fork.
peetee
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Re: First time fitting Folks

Post by peetee »

Something doesn’t look right to me. Item 7 looks radiused as if it is designed for open bearings. Where is the headset from?
The older I get the more I’m inclined to act my shoe size, not my age.
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531colin
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Joined: 4 Dec 2009, 6:56pm
Location: North Yorkshire

Re: First time fitting Forks

Post by 531colin »

As it happens, I assembled exactly this headset a while back (supplied with a Genesis frame).
I have to say that I found Gregory's post a model of clarity....I could no more take somebody else's photos and apply numbers to them than fly about in the air.
Not only that, but he is spot on with the assembly instructions, including the plastic washer thing which offers some slight "sealing" to the bottom race. Chapeau!
Scudders
Posts: 14
Joined: 19 Aug 2020, 7:59pm

Re: First time fitting Folks

Post by Scudders »

gregoryoftours wrote:The headset needs to be assembled as follows:

IMG_20200819_215120.jpg
IMG_20200819_215339.jpg
Part 1- this is the crown race. Flip this 180° and it needs to sit around the stepped shoulder it is currently sat on top of, with the bevel facing upwards. If it's a split collar it will just push down around the shoulder on the fork. If it's not a split collar it will need installing by tapping it down carefully into place with a piece of pipe of the correct internal diameter, or using a proper headset crown race installation tool.

Remove part 6 for the time being - it belongs in the top half of the headset.

Due to the large internal diameter of the plastic ring (labelled seal ring) I suspect that it's a basic seal designed to rest on the ledge surrounding the upward facing bevel of part 1. If this binds when the headset is put together it probably belongs somewhere else.

Part 2 - This and part 5 are the cartridge bearings. If the markings are the same on both then they are interchangeable. If not you need to find out which is the upper bearing and which is meant to be the lower and install accordingly. If they are both the same then this fits as it currently is between the upward facing bevel of part 1 and the inside the lower headset cup 3. As it is now part 2 is the correct way up.

Part 5 - the upper bearing sits as it is into the upper cup 4. It's the right way up already.

Part 6 - compression ring. Install this split ring, bevel facing down, onto bearing 5. It should wedge into the internal bevel of the bearing.

Part 7 - bearing cover/dust cap. The radius on this can be a little confusing, it faces up and is just like that to look neater meeting the steerer spacers that fit above it, it's not any kind of a bearing race or cone. Flip this part over so that the flat underside sits on the flat top of part 6. The rubber skirt faces down, stopping water/dust getting in. There is a small possibility that if the plastic ring mentioned earlier causes the headset to bind it may instead belong around the outside of part 6 and under the rubber skirt of 7, but I don't think that is the case.

Then your steerer spacers and/or stem stack on top of part 7 as usual.


Thanks for the response gregoryoftours. This made the most sense, hence time to crack on. And as soon as I do I hit a wall of uncertainty.

Any Advice on whether the crown race should fit right snug to the bearing or not?

Both of the Cassette Bearings are identical and fit really nicely to the compression ring. Should the fit be the same with the Bearing and the Crown Race?

instead the bearing seems to just sit on top of the crown race and only slightly engage/overlap. I'm hoping this is normal?

Thanks again.
Scudders
Posts: 14
Joined: 19 Aug 2020, 7:59pm

Re: First time fitting Forks

Post by Scudders »

531colin wrote:As it happens, I assembled exactly this headset a while back (supplied with a Genesis frame).
I have to say that I found Gregory's post a model of clarity....I could no more take somebody else's photos and apply numbers to them than fly about in the air.
Not only that, but he is spot on with the assembly instructions, including the plastic washer thing which offers some slight "sealing" to the bottom race. Chapeau!


When you assembled did the crown race fully engage with the bearing, as in fit up nice and snug to each other? The crown race and the bearings don't seem to fit as they should and only partially engage. I'm wondering if this is normal... or not. Both bearings are identical.

Cheers
Jdsk
Posts: 24827
Joined: 5 Mar 2019, 5:42pm

Re: First time fitting Forks

Post by Jdsk »

Could you add a photo of the current state of the assembly?

Jonathan
DevonDamo
Posts: 1039
Joined: 24 May 2011, 1:42am

Re: First time fitting Forks

Post by DevonDamo »

You've already been given the info you need to solve the crown-race/bearing mating problem - have a read back through and see if you can spot it.
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531colin
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Location: North Yorkshire

Re: First time fitting Forks

Post by 531colin »

The bottom cartridge bearing seats on a short 45 degree taper on the top of the crown race. (the tapered centre of the bearing seats on the taper on the crown race.) However, thats enough to keep the forks and head tube concentric, which is all it has to do.
The compression ring taper leads into a plain (parallel) bit of the compression ring which fits inside the plain (parallel) bit of the bearing, so it is a more "positive" fit between the top bearing and the compression ring. (than between the bottom bearing and the crown race.) The compression ring needs to have a good contact area with the steerer tube in order to keep the compression ring (and therefore the bearing) square to the steerer; the crown race seats on the crown race seat, so its always going to be square to the steerer.
In short, the seating of the 2 cartridge bearings is different!
DevonDamo
Posts: 1039
Joined: 24 May 2011, 1:42am

Re: First time fitting Forks

Post by DevonDamo »

531colin wrote:The bottom cartridge bearing seats on a short 45 degree taper ...


All true, but he's missed something else...

(Edit: ignore me... I thought he'd left the spacer at the top of the crown as shown in his first photos. His recent photo shows otherwise.)
Last edited by DevonDamo on 23 Aug 2020, 10:11pm, edited 1 time in total.
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