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rebuilding an old 1" headset

Posted: Sat Apr 12, 2008 7:42 pm
by HappyHumber
Ok, in the process of rebuilding my commuter, I am weighing up various parts & pieces that I want to transfer between my two 80s era 10/12 speed road frames.

My preferred headset came out off the MBK; It's a branded Shimano, unlike many other verge freebies I've found & dismantled. Whilst it's not a sealed bearing unit, it has a serviceable grommet/seal ring that sits around the crown race and makes for a relatively, clean & neat unit. The thing is... in my over zealousness in dismantling this headset I crushed one of the bearing cages slightly, and instantly lost most of the ball bearings themselves. No big deal I thought - I should be able to get a replacement from one my LBS.

I've been to two Shops this afternoon with no luck - like the cheapo headset I pulled out of the Ricardo frame I am now building up (and was wanting to use the MBK/Shimano HS on) all the two stores had in stock were the caged bearings were about 0.5 - 1mm greater in diameter and too big to fit in the MBK's Shimano cups.

The nicer Shimano unit has the same inner crown race diameter and outer cup diameter to mount in the headtube as that pulled off the Ricardo - but it seems the bearing seat diameter is slightly smaller between the cups & the races :(

Should I be having this trouble getting the right replacement bearing?
Should I just kiss the nice Shimano headset goodbye and resign myself to a cheapie complete replacement unit ?

Kymbo

Posted: Sun Apr 13, 2008 9:27 am
by LuckyPierre
Try Moruya Bicycles - they have a fair few headset spares.

Posted: Sun Apr 13, 2008 12:34 pm
by tallywhacker
headsets will always run better with bearings out of the cage. Most LBS's should have replacement BB's but I know (from experience) that Elite Racing Cycles definately has loose BBs

Posted: Sun Apr 13, 2008 12:51 pm
by Kalgrm
Yep, you don't need the cage, just the bearings. The cages were used to make assembly at the factory quicker, not for any performance gains.

Just use grease to hold them in place while you put the fork into its correct place.

Cheers,
Graeme

Posted: Sun Apr 13, 2008 1:04 pm
by HappyHumber
thanks Tally & Graeme

that thought did cross my mind - I asked one of the kids that served me about just packing them with grease & the right size loose bearings - and he said they'd just flog out in no time. This didn't seem right to me. As far as my limited experience & understanding goes - assuming the same number & size of bearings the only advantage the cage would offer is ease of handling. Perhaps he thought I meant pack it with what bearings I had left; I was actually just thinking of comparing the ball sizes between cages and pulling the balls out of a different diameter cage - even if that meant I had to buy couple.

I spose this was a reflection of why the two places I visited yesterday aren't my preferred LBS. They tend to only do in a pinch, when it's nothing outside of the ordinary. Their immediate reflex beyond the token scratch through the parts box was to try and sell me a complete new headset.

Anyway, out to enjoy some of today's sunshine... I have a fork crown brake hole and seat clamp to drill out a bit ;)

Posted: Sun Apr 13, 2008 6:29 pm
by tallywhacker
Quite a few ball bearing auctions on ebay capn queeg

Posted: Sun Apr 13, 2008 7:22 pm
by HappyHumber
Yeah.. sheesh.. you're right.

I can easily count how many bearing there were in the old cage, no worries. but measuring the difference between 5/32" and 3/16".. yeegads!

I realised for some reason I had quickly cleaned up a lot of the old cheapie 1" sets I had pulled apart previously. I have a number of other bearing cage sets tucked away in a box. I might just sit down and even if I can't find a full cage with a diameter to match I'll see how well I can match the ball sizes to that's what left in the original cage and make up the original number and reinstall sans cage.

Of all the money I waste on other things - here I am counting loose second hand ball bearings..... :D

Posted: Sun Apr 13, 2008 7:37 pm
by il padrone
HappyHumber wrote:I can easily count how many bearing there were in the old cage, no worries. but measuring the difference between 5/32" and 3/16".. yeegads!
But take note that if you use loose balls you will need a few more balls than are in a cage. Generally you fill the race with balls, held in place by a line of grease, but leave a space of 1 or 2 balls.

I reckon this is one advantage of loose balls over a caged set, more balls to spread the load more. Dunno if there's any engineering truth in it though :wink:

Posted: Sun Apr 13, 2008 9:12 pm
by HappyHumber
il padrone wrote:But take note that if you use loose balls you will need a few more balls than are in a cage. Generally you fill the race with balls, held in place by a line of grease, but leave a space of 1 or 2 balls.
Nice point, thanks il padrone.

Of all the old cast off clunkers I've pulled apart, this is my first actual rebuild of similar vintage components. I haven't actually even done a hub bearing repack yet - but I do know enough not to ram as many as possible bearings in there - round about 1 balls worth of space should be kept free I remember someone saying - your suggestion for the headset bought this to mind. And those cages I have been looking at today are pretty well spaced out. I'd imagine if the balls were all next to one another - there'd be a considerable gap.

Anyway.. now I realise I need a 32mm headset spanner to properly reassemble, preload/tension this sucker. Just taking them apart with my 12" crescent spanner never taught me this ;)

Kym

Posted: Sun Apr 13, 2008 10:34 pm
by tallywhacker
dare I say that tonight you are going to sit down and play with your balls ? :wink:
If you take them out of the cage you will need and extra ball to fill the space left by the cage