any tips for a really tight crown race?

Pierre, that might work with a relatively loose crown race, but with a tight one you’ll just strip the top bolt or knacker the bearings. Same reason you take care when pressing the cups in – pressing on the bearings can ruin them.

really ? how, exactly would it have those effects ?

I have a bit of experience in this area 😉

Right tools for the job?? Fork crown reducing tool… crown race fitting tool,headset facing tool… I have a few 8)

But basically there are so many variants? if you split a race that is from a headset that is not designed to have a split and force it over the incorrect sized fork crown, it doesn’t allow the cartridge bearing to sit properly? the bearing sits high which can leave it exposed to elements?, corrosion?and washing? which in turn decreases the life of the headset. It also reduces the designed contact area between the the two parts slackening the angle on the race compared to the angle on the bearing. The bearing race circumference is increased too! which means even if the lower cup covers the bearing? the cup could possibly make contact with the bearing race and jam? more so if the head tube has not been faced too ..and yep! I have seen this 😛 …. but .. over 25 years of fixing, fitting headsets at a professional level means, more info? would require me to ask you for your card details! 😉

but yet… you may know as much as me 😀 who knows may be even more?

Sorry for the brain fart… it’s late… and I’ve not nearly had enough alcohol …

gunna fix that right now 😀

oh this is good.
Chris King

What the hell’s going on with all those question marks?

basically King think (10 years ago) that headsets that don’t need cups are Very Bad.

To do it properly you need one of these

Then some of this

or any old grease will do really.

Then one of these

Do NOT cut the crown race on a reducer headset.

Out of interest, (haing never had to resort to cutting a headset crown race) when you have a very tight fitting non-split race, is it the race that stretches round the ever-so-slightly-wider steerer, or is it the steerer that is compressed?

I understand that a reducer race is a different issue, but the reason I ask is that all this concern in previous posts about widths of races that weren’t supplied split (and are split by the installer) is surely worth naff all when you can put a (supplied) split race cane creek 110 headset on both tighter and slacker fitting steerers and if done so correctly still have the 110 year garauntee.

I heated one up slightly over the gas ring then leaving it to cool once fitted it tightend up a treat.

Out of interest, (haing never had to resort to cutting a headset crown race) when you have a very tight fitting non-split race, is it the race that stretches round the ever-so-slightly-wider steerer, or is it the steerer that is compressed?

Well, “very tight” is subjective – if the fork is prepped with the cutting tool properly first, then it’ll be tight and require a decent hit or three to get on, but not silly tight. But to answer your question, a bit of both – it’s an interference fit, so the tube compresses a bit and the race expands a bit.

But it expands a lot less than a split race would do. Of course with older headsets without cartridge bearings, the race is really a bearing race, rather than a spacer – for them it’s even more critical, but there are no issues with the bearing surface expanding.

Still laughing uncontrolably at Pierre-those whacky frogs eh!?!?!

I heated a stubborn one with a ciggly lighter and it popped-on a treat. Could be a pain if I ever want to get it off though.

bencooper – Member

But to answer your question, a bit of both – it’s an interference fit, so the tube compresses a bit and the race expands a bit.

But it expands a lot less than a split race would do.

bencooper, surely supplying a split race encourages people, (even bike mechanics with the proper tools!) not to bother prepping the base of a fork steerer, because the split race will go on by hand or at the very worst, with a couple of rather light taps of a setting tool. I have certainly come across plenty of big brand complete bikes from £500 to £3k with unprepped steerers and crowns and split crown races.

IIRC the cane creek 110 headset 110 year garuantee is conditional on proper installation with a proper headset press, but not conditional upon the steerer/crown having been reamed/faced.

Sorry if I am being dumb here (or missed something further up).
What preparation is needed to the base of the fork steerer and crown, and why? I check for nicks, dents etc but on a new steerer this should be fine. I assume the crown doesn’t matter too much (unless it is obviously compromised) as the race will make contact with the bearings, not the crown.

Have I missed something ❓

bencooper, surely supplying a split race encourages people, (even bike mechanics with the proper tools!) not to bother prepping the base of a fork steerer, because the split race will go on by hand or at the very worst, with a couple of rather light taps of a setting tool.

That’s a good point. I suppose the contrary argument is that if it’s a spacer for the cartridge rather than a true race it matters less. But sure, proper preparation is best.

What preparation is needed to the base of the fork steerer and crown, and why?

The diameter needs to be correct, and the seat needs to be perfectly square – i.e. the race needs to sit perfectly flat.

You mean forks are supplied not fit for use? Blimey!

Shocking, isn’t it? 🙂

Why is everyone so worried about headsets, just bash em together I say, a nice mallet job done, if a race is uber tight wet and dry it until its a normal fit.

FWIW I would not take my forks to anyone armed with anything to cut them or remove material from where the race sits, adjust the replacable part in my opinion.

check your diameters with a micrometer, if you are a the upper end of the tolerance band, it will be pretty tight.

http://s15.postimage.org/xwswrdaob/crownrace_fit.jpg

Cheers Ben – thought I’d missed somehting more fundamental when I’ve been fitting them.

😆 @ smiff , “very very drunk!”

What the hell’s going on with all those question marks?

Nasty habit! .. I explain it away by saying it’s to give a rising inflection at the end of every sentence a bit like the Aussies?

The truth is it’s from my subconsciousness, it expresses my self doubt by needing acceptance through acknowledgement of everything I say by others… or.. I was pissed and knackered!
😀