Headset for Giant TCX frame

garethrl

Hi folks,
I bought a Giant TCX 'cross frame on ebay early last year. It was listed as being about a season old so either a 2007 or 2008 and I reckon '07 is more likely. I can't work out what headset it needs though! In fact I can't even establish what type of headset! Google throws up a variety of results mostly claiming either an integrated or zero-stack headset, but even one listing a standard threadless aheadset.

I measured the ID of the headtube to be 41mm in the relieved section which seems to be more in line with needing an integrated headset, except the relieved part doesn't like the equivalent for other frames I've seen that are clearly set up for integrated h/s. This one doesn't look 'finished' enough, and there's no angled surface to seat the bearing on. It definitely looks like it needs some press-in cups to house the hearings - but all the zero-stack headsets I've seen have cups with OD 44mm, or 42mm in some rare cases. Eve the FSA headset manual doesn't list any with 41mm OD.

I could take and post a couple of pics if that would help? Hopefully somebody will know though. I emailed Giant UK and they were no help.

TIA for any help,
Gareth.

Monty Dog

There's a good guide to headsets on the FSA website

Captain Fagor

I had similar problems when building up an '06 TCR.

I know what you mean when you say that the inside of the headtube doesn't look finished enough, and has no taper. I expect it looks something like the inverted Giant headtube (grey colour) shown on the Park tool website:

http://www.parktool.com/repair/readhowto.asp?id=68

You might think this would seemingly rule out a standard IS-2 type integrated headset (as the frame is not shaped to receive a bearing), and make you think of zero-stack. Only the inside diameter of the head tube isn't big enough for the press fit cups of a zero-stack.

I believe the solution is that some integrated headsets come with split crown races that fit into your frame, thus forming the required polished tapered surface that you require for a 36/45 degree bearing. The FSA Orbit CC No. 16 was one example. I bought mine from Wiggle at the time, but they don't seem to sell them anymore. My money would be on the FSA Orbit IS being the one you want.

Annoyingly, I don't have any spares to make sure I'm not misguiding you, but if you don't make any progress, let me know and I can strip one of my Giant TCR headsets (I have two) and check.

Captain Fagor

Just noticed - you can see what I'm on about in the park tools website link above. Read the "Integrated- Angular Contact System (without cups)" section, and look at the picture of the yellow headtube immediately above the title for "Campagnolo Hiddenset".

garethrl

Thanks for the link to the Park site and the comprehensive lookup table. It's good to see all the pertinent info on the various standards collected and to establish there are only two sizes I need to consider, not three as I'd feared. Also good to know definitively that zero-stack requires press fit installation.

I've measured the ID of the headtube a few times now and it's definitely closer to 41.3mm than 41.0mm so I guess I was a bit unlucky with the headset I got which was closer to 42.0mm. If I can get one closer to the notional 41.4mm mark then I'd be happy to ream out the headtube a bit as there's enough material there to remove a bit - the OD of the headtube is 46mm so taking off say 0.2mm all around shouldn't hurt. This one here might be the best candidate:

http://www.chainreactioncycles.com/Mode ... elID=39377

As for the press-in retaining rings, when I drop the 41.0mm bearing in place for reference, it sits a long way down from the top of the headtube. Looking at that split ring in the picture, I'd be a little surprised if it raised the bearing far enough so it was flush with the top of the headtube - but you never know! I'll try again for a 41.4mm zero-stack as the shop that sold me the last 44mm version are looking to see if they have one. In the meantime I'll try to track down a pair of split rings.

OTOH, wouldn't you be able to tell from visual inspection if your TCR has a zero-stack or integrated headset? If the former then you should be able to see the lips of the two bearing retainers seated at the top and bottom of the headtube. If the latter you'd have a clean, uninterrupted look like the front-end pic at the start of the section marked "Integrated- Angular Contact System (without cups)" (about 1/4 of the way down).

Thanks again for your help,
Gareth.

Captain Fagor

Thanks for the reply.

I can tell you that my TCR headset is definitelty not of the semi-integrated (i.e. Zero Stack) variety. As I said, it's like the "Integrated- Angular Contact System (without cups)", only I think there's a split crown race above the lower bearing and below the upper bearing.

Like I say, If you're really stuck, I can strip one of mine and if it fits the same description as yours (shape and mesurement wise), post some photos.

I'd avoid any frame alterations - I think this would cause more grief than it's worth and potentially be unsafe.

Captain Fagor

Just thought I'd strip it anyway - the uncertainty was annoying me.

As i thought, there is indeed a split crown race which gives the required running surface for the bearing. The pictures below are probably worth a thousand words. The removed components are positioned in the same order as you would read a book.

The headtube OD is 46.6mm, and ID is 41.2mm which reduces to 38.6mm at a 90 degree step positioned 10.4mm into the headtube (both at top and bottom). The bearings are 36 x 45 1+1/8" efforts. Pretty standard fayre.

http://img.photobucket.com/albums/v625/ ... Photo1.jpg

http://img.photobucket.com/albums/v625/ ... Photo2.jpg

http://img.photobucket.com/albums/v625/ ... Photo3.jpg

http://img.photobucket.com/albums/v625/ ... Photo4.jpg

http://img.photobucket.com/albums/v625/ ... Photo5.jpg

garethrl

Cool! You're an absolute star!

Thanks for measuring the depth of the relieved section. I measured mine to be about 10mm as opposed to a bearing thickness of slightly over 6mm - hence my apprehension about the split ring lifting the bearing up far enough. From your description it seems it's right on the money.

The OD of the headtube sounds about right too. Now all I need to do is track down a pair of those clever split rings ...

Cheers, and thanks a million,
Gareth.

Captain Fagor

Aw shucks. :oops:

Regarding replacements, if I were buying again - which I soon will be, as I like to keep spares - then in leiu of the FSA Orbit CC No. 16 I'd go for the FSA Orbit IS. It looks the same to me. Let me know how you get on.

Lastly, if you're in the market for some grease for the headset rebuild, get some of this stuff - it's excellent:

http://www.chainreactioncycles.com/Mode ... delID=2611

Good luck!

garethrl

Ok, the scenario is becoming a bit clearer ...

I've just spent a while poring through the FSA heaset reference guide - which you can download from here - and the only headset listed there which is supplied with the split rings is the Orbit SPX, also known as No.26G. You can see it on page 33. It uses the same angular contact bearings as most of the other IS headsets in the range but it's the only one that provides the split-ring inserts required to seat the bearings.

However, a google search suggests it's very difficult to find! So looking around and thinking a bit, it looks like my options are:

1) wait til find the FSA Orbit SPX IS headset, the one that was originally intended for the bike

2) since I know 'everything' I need to know about the split-ring inserts, try to have a pair machined and buy a different IS headset, probably another FSA

3) try to find a ZS headset with 41.4mm OD press-fit cups, like this one or this one. The first has inferior bearingg while the second has a slightly higher stack height than I wanted. I reckon I could find a sealed bearing to fit the first or a shorter stack for the second though

4) get some reduction cups machined to run a standard threadless headset instead. Again the higher stach height will give me bother since the fork steerer has been cut to use with a ZS or IS headset and I'd rather not have to change it

5) get a ZS headset with 42.0mm OD cups and ream the headtube out a bit - this would involve thinning the headtube walls by 0.3mm all round, from 2.8mm this to 2.5mm, a reduction of 10.7%. 10.7% sounds a lot more significant than 0.3mm, doesn't it?!

6) ... anything I've overlooked or am too stupid to think of

Don't you just love bike industry 'standards'?!

Cheers, Gareth.

Captain Fagor

Now that you know the component you're looking for, I'd give Giant / FSA / your LBS a call.

I'm beginning to wish I'd bought a spare when they were still widely available! :roll:

garethrl

Just make sure you hang on to the steel split ring inserts - the bearing is a standard 873-2RS ACB unit that FSA use across the range of IS headset. As long as the inserts last you're free to replace the entire headset as often as you like.

EDIT: apart from the fact that the upper bearing cover will probably be the wrong diameter,,that is ...

Me, on the other hand ... that's a different story! I have ads on a load of forums and have emailed my LBS. Let's wait and see what happens ...

garethrl

Getting there slowly ...

According to this posting, Hope provide the same split ring seat with their IS headset. If you take a look at this diagram the seats are clearly there, and according to the mtbr thread above the parts worked with a third party headset in a Giant NRS frame with the same head tube spes as mine.

My LBS is a Hope dealer and they'll try to order just a pair of the bearing seats as I already have the Ritchey WCS that I can plunder for parts. If they're not available as spares any more then I'll buy a headset, can't go wrong with Hope bearings after all.

Wish me luck. I'll update on progress ...

Captain Fagor

Good investigation - you're getting there!

Let me know how you get on with buying the Hope bits. If all else fails, CRC have the Hope headset in stock, but it's £61.

FransJacques

I have a 1" headset on a 2001 TCR and am grappling with getting new cartridge bearings for it. When they call it a 36/45 cartidges, does that mean it takes 1x 45 and 1 x 36? Which one goes on top?

My headset clunks over bump yet is stiff at the handlebar to turn so I have excess play I cannot take out of the system.

Getting new bearings is just 1 step to sorting the whole mess out.

Thanks for your help.

garethrl

Each angular contact bearing (ACB) has two angles and this is how you tell which ones you need as a replacement. For your headset you just need two 36/45 ACB's - which as luck would have it is more or less the most common size.

The 36 means that the angled section on the inner face is machined to 36 degrees, while the 45 means the outer face is machined to 45 degrees. That in turn means that the seats inside the headtube have also been machined to 45 degrees while at the same time the crown race and compression ring are at 36 degrees. Other standards are 36/36 (rarer) and 45/45 (mainly Campagnolo).

Anyway, IMO your problem sounds like a mismatched system somehow. Are you sure they've not already been replaced, and with the wrong ones? As you can imagine, if you try to drop a pair of 36/45 ACBs into a headtube designed for 36/36 (or vice versa) and use the old crown race and compression ring, then it's just not going to work. When you remove the top cover, does the bearing sit more-or-less flush with the top of the head tube? Are the crown race and compression ring sitting flush in the bearings?

Also, everything I've written above assumes you have integrated systems on the TCR, which I think is indeed the case. A quick google search suggests TCRs mostly using Cane Creek and FSA headsets so 36/45 should be right.

Good luck anyway!

Cheers, Gareth.

garethrl

Anyway, back to my original problem, and the good news is that I've fixed it! The Hope bearing seats slotted in a treat and everything else just sat in place above or below it. The upper ACB sits a bit lower in the head tube than I expected, but I found a combination of compression ring and thin spacers that got around it.

So far I've only assembled the unit and tightened up the top cap to take up the slack. I haven't yet wired up the brakes and locked up the front to see if there's any play, but I'm feeling happy with the night's work so will do the rest tomorrow! I'll report again when it's fully set up.

The Hope bearing seats are £1.99 each, by the way, and the rest came mainly from a standard IS headset.

Cheers, Gareth.

Don1

The correct headset can be ordered from Giant via your local Giant dealer. It is an 1 1/8 ntegrated threadless sytem compatible with Giant composite frames. Part No. 49008

tgotb

I found this thread while searching for a headset for my 2008 Giant Trinity C, which requires the same spec headset. For anyone else who stumbles across this thread in the future, JE James had the headset in stock as of mid 2013:
http://www.jejamescycles.co.uk/giant-ro ... .html#info
Includes all the bearings, races etc that you need...

shr1nk

Late contribution to this thread.

CRC sell the FSA OEM Giant headset for OCR, TCR, CRX, etc.

Only A$7.99

http://www.chainreactioncycles.com/au/e ... -prod90218

Giant specific part
1.1/8" steerer
41mm internal diameter Top & Bottom press-fit
Stack height: 5.6 + 2.9 = 8.5mm.