1" fork crown race setting isue..

Bike Forum

1" fork crown race setting isue..

15 posts & 9 voices | Started 8 months ago by slimjim78 | Latest reply from walleater

Tags:

No tags yet.

slimjim78 - Member

Trying to fit a 1" Chris King crown race to my 1" steel road fork.

Am even using a Park race setting tool. Trouble is the race seems just a bit too tight to seat on the fork, its sticking on the lip that its supposed to be pressed against.
Despite a hefty whack, the crown race just sits there, loosly fitted.

Do I need to have the base/lip of the steering tube reamed to remove a tiny amount of material, or do I need to get more hefty with the mallet?

I dont want to whack much harder for fear of bending the fork drop outs on the work surface.
Never had this problem with 1.1/8th, is it a 1" thing?

Posted 8 months ago #
18bikes - Member

I would suggest getting the fork to a shop with a crown race cutter to check that the fork is the correct size. 1" should fit in exactly the same way as a 1 1/8'

Hope this helps

Matt

Posted 8 months ago #
stAn-Bad Brains MBC - Member

forks in freezer - race on heat ???

worth a punt IMO

Posted 8 months ago #
slimjim78 - Member

both good advice, thanks

Posted 8 months ago #
andyl - Member

dont wack down onto the drop outs - use something under the bridge. TBH I hold the bridge in one hand and bash down with the other - that way no damage to anything.

Might be LBS time though as it would be best to check the sizes.

Posted 8 months ago #
slimjim78 - Member

I dont get what sizes there are to check?

I understand there are different tolerances, but its not like i can order a different size 1" king race is it?..or is it?

Posted 8 months ago #
andyl - Member

It is the tolerance I would want checking.

Posted 8 months ago #
frank4short - Member

Failing all of the above, though i reckon the freezer heat idea is the best so far, if you're feeling brave gently file a small amount of material off of the crown race seat on the fork. As unless your LBS is particularly good they're unlikely to have a crown race cutting reamer set let alone a 1" crown race shoulder cutting die. Which means they'll probably be doing this themselves anyway.

Posted 8 months ago #
slimjim78 - Member

just tried applying heat, no joy at all (doesnt heat apply expansion inwards as well as outards to a ring?).

might be tempted to file a minimal amount of the shoulder down, but can detect the cringes already..

Posted 8 months ago #
andyl - Member

no the whole ring will expand - the perimeter is longer than the width so the total expansion will end up in the outer and inner diameters being bigger.

I think I'd be more tempted to file a chamfer onto the crown race - at least that is replaceable.

They do undersize ones: http://chrisking.com/parts/baseplates

maybe the one you have is one of them?

Posted 8 months ago #
MTB Rob - Member

Are the bearings Cartridge type bearings and NOT lose bearings?

If cartridge bearings, get a hack saw and cut a Slot in the the crown race.
De-burr etc, and fit, the race should spead a little and fit onto fork.
And with a cartidge bearing having it own "race" to run on you don't feel the slot.
Also it is a lot easier to remove the crown race at a later date if needed.

Posted 8 months ago #
letmetalktomark - Member

IIRC BITD some 1'' forks required a larger than std crown race.

I have experienced exactly what the OP describes and only remedied it by using a split crown race

Just a thought.

Worth a measure up I guess.

Posted 8 months ago #
slimjim78 - Member

its a Chris King headset & 'race' (base plate).

Not sure of the effect that cutting it would have, being King quality and all that..

Ive called a fairly local LBS and they reckon they can do the job, but I detected a sense of 'not quite sure what you mean' when I was describing the issue over the phone so not sure I want to hand the fork over for reaming as its the original one supplied with the frame back in '98.

The base plates are sacrificial to an extent, so may have a go at splitting it unless anyone here screams no to.
Or may take the fork to LBS and see what they say in the flesh.

Posted 8 months ago #
taxi25 - Member

I've split crown races before, never had a problem. Some fsa models come split as standard.

Posted 8 months ago #
walleater - Member

There's two 1" headset sizes:

http://en.wikipedia.org/wiki/Headset_(bicycle_part)#Headset_sizes

So if it's not clearing the ramp, there's a good chance that you are trying to hammer a 26.4 race on to a 27.0 steerer, and you will probably crack the race.

Posted 8 months ago #

RSS feed for this topic

Reply

You must log in to post.

Singletrack Mountain Bike Magazine

Bike Forum

1" fork crown race setting isue..

Reply

Don't miss…

Singletrack

Website & Forums

Exits