Replacement headset bearings for Giant TCR?

schemieradge

Hi,
The steering on my Giant TCR Advanced 2 (2019) has become fairly stiff and notchy.
I'm going to try loosening off the headset bolt (with the stem bolts undone obvs), but want to prepare for replacing the headset bearings and haven't had time to disassemble the headset yet to look..

I found a websites that suggested, for all Giant TCRs I need:

Upper – MH-P08H8 – 41.8 x 30.5 x 8 – 45/45 degree
Lower – MH-P22 – 46.9 x 34.1 x 7 – 45/45 degree

1. Can anyone confirm this is correct, or point me at another source of info?
2. Are replacement bearing all much of a muchness or are there recommended manufacturers you'd want to stick with?

Thanks

schemieradge

Well now I've dismantled the headset I can see the above information is not completely accurate...

Top bearing imprint "MR1211-1/8 45x45 K8"
Bottom bearing - mostly rusted over so I can't read it..
Starts with "MR180" I think and measures 46x34x7.
So none-the-wiser on the exact bearing.

As it turned out the bottom bearing was gunked up with loads of muddy rust - so just cleaning it and putting it back has improved matters a great deal.

Would still like to ID the bearing for future replacement though..

schlepcycling

Easiest thing to do is measure the inside diameter, outside diameter and height of each bearing and put those numbers into Google.

MattFalle

you could pop into the Giant shop in town and ask them.

photonic69

Email these guys. Very helpful

https://www.giantbikespares.com/products.php?type=2&subcategory=34&p=1&category=15&b=426&s=n

dj58

It will be Giant's standard OD 1 1/8" to 1 1/4" 45deg. / 45deg. ACB for a tapered steerer tube.
https://www.giant-bicycles.com/gb/giant-od-road-headset
https://shop.fullspeedahead.com/en/type/headset-spares/headsets/road-mtb-urban-commuting/no-44e
Download the NO.44E_Service Doc.pdf file, shows a table with the bearing reference numbers.
Item 5 Top MR121(870E-RS)
Item 6 Bottom MR168(970E-RS)

schemieradge

This is amazing! Thanks very much...

dj58 said:

It will be Giant's standard OD 1 1/8" to 1 1/4" 45deg. / 45deg. ACB for a tapered steerer tube.
https://www.giant-bicycles.com/gb/giant-od-road-headset
https://shop.fullspeedahead.com/en/type/headset-spares/headsets/road-mtb-urban-commuting/no-44e
Download the NO.44E_Service Doc.pdf file, shows a table with the bearing reference numbers.
Item 5 Top MR121(870E-RS)
Item 6 Bottom MR168(970E-RS)

dj58

Your welcome. Click on the image of the ball bearings to show more details.
https://simplybearings.co.uk/shop/advanced_search_result.php?search_in_description=1&keywords=TH-870&
https://simplybearings.co.uk/shop/advanced_search_result.php?search_in_description=1&keywords=TH-970&