Classic & Vintage - Help! I need a JIS crown race

That Centurion rebuild I posted up a little while back...I took it on its first long ride, and noticed something wrong feeling with the steering. So I put it on the stand and took a look at it, and there was a bit of wiggle in the steering column. At first I thought I just needed to tighten up the headset, but if I tightened it up enough to take the play out, it felt like the bearings were grinding.

So I dropped the fork out to see if the bearings were on upside down. Which is when I discovered that there's no crown race. Yikes!

(I didn't install it.)

So, I need a JIS crown race. The bike shop is in San Antonio, and he can't find the crown race right now.

The headset is a 105 1" threaded. Sealed cartridge bearings. I think it probably came with an ISO standard race, and the shop wrenches couldn't get it on, so they just left it off and didn't tell anyone. Now I'm just hoping that the JIS crown race will fit.

What a pain.

Can any of you guys help?

Cheers!

JIS Shimano headset crown races used to be commonly available. I haven't checked for one in awhile, but figure they probably still are.
First thing you should do is contact the owner of the shop where you got the headset installed so they can do something to prevent this kind of dangerous incompetence from happening again.

Look at the tange sekai crown race on this page 27.0 mm............$1.95 plus a little shipping.........http://www.bikemannetwork.com/category.php?code=COMPHSPRTCRWN&store=1&p=2 I had to use one like this on my Ironman with a headset I purchased that came with a a 26.4mm crown race. I was wondering why I couldnt get that damn thing on ....:DLOL!

It occurs to me that it's possible a crown race not designed for cartridge bearings may not work.

I'm a bit steamed. At the time I took this bike in, I didn't have a set of calipers to measure. That's WHY I took it in instead of doing everything myself. I asked them to check to make certain the bike wasn't JIS (which I suspected it may be) before they installed anything.

Now I have digital calipers. And after I removed the fork it took a quick measure to find that it is indeed JIS.

An easy solution would be to simply return the headset and have them order a Tange JIS headset. However...the ISO cups are larger than the JIS cups, and have likely stretched my headtube to where a JIS headset won't fit anymore.

This is why I always do my own work. However, lacking the tools in this one case (no headset press either) I let the shop do it.

I hope I didn't trash this bike. I put a LOT of work into getting it up and running again.

Look at the tange sekai crown race on this page 27.0 mm............$1.95 plus a little shipping.........http://www.bikemannetwork.com/category.php?code=COMPHSPRTCRWN&store=1&p=2 I had to use one like this on my Ironman with a headset I purchased that came with a a 26.4mm crown race. I was wondering why I couldnt get that damn thing on ....:DLOL!

I just checked out that link. There are a number of JIS crown races there. (Funny that place didn't come up with a google search!)

Do you happen to know which one will work with a sealed cartridge bearing headset?

I don't see any one that's a *guaranteed* fit with your Shimano 105 sealed bearing unit. Most of these JIS races are for a specific brand and model open-style headset.
I advise you go to an *experienced* shop and pay for the crown race to be milled to accept the 26.4 standard, then use the race that came with your 105...problem solved.

I don't see any one that's a *guaranteed* fit with your Shimano 105 sealed bearing unit. Most of these JIS races are for a specific brand and model open-style headset.
I advise you go to an *experienced* shop and pay for the crown race to be milled to accept the 26.4 standard, then use the race that came with your 105...problem solved.

Is there a specific tool for that, or would it just be done with a grinder/dremel/something similar?

there is a specific tool (actually tools, VAR, Park, and others make them) that a good LBS that deals with vintage bikes should have. Don't try to DIY it with handtools unless you are prepared to deal with egg-shaped or undersized crowns (and have a supply of LocTite Green on hand). The last time I paid somebody to mill a crownrace it was about $18, but that was years ago...worth the money, anyhow.

I just checked out that link. There are a number of JIS crown races there. (Funny that place didn't come up with a google search!)

Do you happen to know which one will work with a sealed cartridge bearing headset?

No idea....I used mine with a Richey Logic Headset.........If you are gonna get your Crown cut down to 26.4, I would try a machine shop before a LBS. Take your crown race with you and show them what you need. Tell them you need a "pressed on" fit. A good machinist will know what that means.