hythamfekry

HI ,
i'm building a road bike using scott addict rc 2011 frame , i had FSA (Mod.Orbit Z 9/M 1 – 1/8 "Semi Integrated Headset/Headset TH 9/M Orbit Z) along with it .

problem is that after fitting crown race at the bottom of the fork , there's a slightly big gap between race and the bearing , accordingly when installing the fork , there's 2mm gap between headtube and fork ..
i thought about buying a different crown race which may have same diameter but with lower height , but i don't want to go through removing the crown race again as it's now very tight fit .







side question .. first problem was that base of the fork had extra epoxy,carbon fiber residue from manufacturing , i used a sand paper very lightly to remove that , that was a batter option for me than pressing to hard on the crown race to make it fit or sand crown race which may make it uneven and damage carbon layers in future , was that the best action to do

'02 nrs

are you certain the bearing+race angles match? looks to be very improper.could you have the upper bearing with diff. angle installed?

HillRider

Any chance the lower bearing is upside down?

Andrew R Stewart 

Not if the second photo is also the way the lower bearing was installed on reassembly. But I do question the match between the lower bearing and the crown race WRT their mating conical angles. I also have questions about how photo 2 relates to #3 . #2 shows the bearing sitting rather high off the crown race yet #3 seems to show the headtube and fork about the common distance from each other.

This might be one of those challenges that has a simple answer which is hard to see without being there. Andy

DOS

The bearing looks like it is not as fully seated on the race as it should be. But seems to me pieces are missing.

In OP pic 3 and on @‘02 NRS PIC, there is a flared section on both the upper and lower parts of the headset. This pic, the two parts at the top specifically, would seem to indicate that the flared section is part of a cover that goes over the top of the bearing in OPS pic. Perhaps that makes up,for the gap?

dsaul

The two parts at the top of that pic are the headset cups that get pressed into the frame.

100bikes

The residue from manufacturing limits the accurate fit of the fork crown race. I am not certain if a traditional mill is going to
work on carbon fiber.

Accuracy of this fit (or lack of it) is imperative in correctly seating these precision parts. Perfect assembly (and function)
depends on the fit of the every element of the headset.

Not being in tune with carbon frames, and what mill to accomplish this, I will say that a headset requires parallel top and bottom faces
on the headtube. If the seating isn't correct at installation, the cups will likely shift on riding, and could lead to binding.

In the Campagnolo pro tool box, there is a measuring die to check the fit before installing the fork crown race.

Lacking a tool like that, a precision caliper and a methodical cleaning of the steerer tube as it meets the fork crown is the only solution I can see.

I killed(ie split) a fork crown race on a vintage Omas headset doing this, and learned a valuable and expensive lesson.

DOS

Duh, I am an idiot

hythamfekry

This is the link for the FSA 'Part number 228882-222' orbit z ..... upper and lower bearing and upper and lower metal cups are identical .. bearing and crown is installed in correct direction :
https://shop.fullspeedahead.com/en/f...444a468b88f78/

hythamfekry

No , i installed it in correct direction as per PDF below
https://shop.fullspeedahead.com/en/f...444a468b88f78/

hythamfekry

yes correct , i installed cups already in frame , but as in second picture , when installing bearing on top of crown , the gap between them seem bigger than it should be , accordingly when installing fork in frame , this gap add up , so there's a gap between lower headset cup and fork "2 mm as in 3rd picture "
that's what weird , this is headset is 1 pack which should be integrated together , but for some reason , crown race height seems to be high ..

hythamfekry

gap is 2 mm , between fork and lower headset cup .. i look higher than it should , maybe the picture don't show gap clear enough

hythamfekry

Do you have same headset , i need to see how crown fit into the bearing , spacing between them

'02 nrs

I have FSA Orbit Z deep cups,zero stack.the crown sits a little high but not as high as yours.also the lower cup COVERS the gap & is sealed by the rubber seal attached to the crown race.lower pic is with bearing inside cup,crown race atop.

hythamfekry

weired my headset have rubber seal only for upper bearings and cup below the headset cap , i suspected my headset have missing parts , but it's the same pieces listed in product pdf i added before in this post .
thanks for the pics ..

'02 nrs

the "bearing marks" could be from an installation tool,no?

DOS

Ya know, I thought that race looked weird.

hythamfekry

Marks from installation as fitting crown was too tight that's why i don't want to remove it again , here is closer look for the race (it's a single one , fork is new came without any races ) , also attached is pdf of headset specs , which shows all parts are here (2 bearing , 2 cups , crown , top cap with rubber piece , open race )

'02 nrs

Have you tried your old crown race on new bearing? PDF says 1.2mm gap.possible new part is not correct,bearing seat not same as bearing angle.have old parts to check-confirm???

hythamfekry

can you elaborate on this (bearing seat is not same as bearing angel) .. now the top split race have a tight fit all the way into the bearing , gap is 1 mm , accoringly it fits into the upper cup , that's not the case for the downside crown race ,
Shall i use pvc tube and use some strokes on it on top of the bearing/crown race/fork .. so it's snug into place ?

hythamfekry

this is new frame (warrant replacement) so it came without race installed , not sure of other race with lower height will fit or not , however i can't know it other race will work or not until i buy it and have it in hand .

hythamfekry

i removed the crown race from.fork here how it looks from inside and downside , gap from outside is at least 2mm

'02 nrs

the gap looks excessive without the deep cup installed.maybe the way this headset is designed.as an extra precaution even though the bearings are sealed,some manufactures advise adding a layer of grease over the seal for extra protection.the upper split ring gap closes/lowers once the bearing cover,spacers,stem are assembled & properly torqued to specs.looks like your doing every thing accordingly,just the way its designed from what I can see.

hythamfekry

ok , but i'm ending up having too much gap between lower headtube and fork , i'm afraid that can put pressure on neck of the fork , also i will end up cutting fork at the wrong point "in case this gap shouldn't be there"