T500 Front hub

Rustygt550 · Post by **Rustygt550** » Thu Dec 10, 2009 2:14 pm

Hi, has anyone came across T500 front hubs cracking around the boss in the centre?

Thanks

Post by **Suzsmokeyallan** » Thu Dec 10, 2009 2:26 pm

Ive heard about this problem but never seen a cracked hub boss. Some of this issue was related to the usage of certain brands of brake shoes.

tz375 · Post by **tz375** » Thu Dec 10, 2009 6:42 pm

Yes,
they have bad habit of breaking (pun intended) They look so good, and are nice and wide but the bearing boss is really weak and they crack. They tend to crack worse on race bikes because the loads are much higher.

Rick Brekkon used to weld the hubs for WERA guys. They will still crack over time - but not so much on a low mileage sunday afternoon bike.

bikegeezer · Post by **bikegeezer** » Fri Dec 11, 2009 8:17 am

Rustygt550 wrote:Hi, has anyone came across T500 front hubs cracking around the boss in the centre?

Thanks

I sold one on eBay, and it was returned to me for small, hairline cracks in the webs around the bearing boss that I had thought were meaningless. The person claimed his current hub had completely broken away at the boss, but I don't see how that could happen from braking forces alone. The brakes grab the hub well outside that area, so any twisting force would be applied between the spoke holes and the brake drum, not at the bearing.

Stu

tz375 · Post by **tz375** » Fri Dec 11, 2009 8:21 am

Stu,

You are right that braking forces do not cause that cracking. It's the side loading on the tire as it corners that pull the wheel sideways relative to the axle.

The area around the bearings is very weak and the radial webs are not enough to stiffen it.

bikegeezer · Post by **bikegeezer** » Fri Dec 11, 2009 8:24 am

Interesting. So is this issue a lot more common than we'd think from the lack of discussion about it? I haven't seen it mentioned on any of the T500 fan sites.

Stu

evol02 · Post by **evol02** » Fri Dec 11, 2009 1:18 pm

I've pulled apart quite a few T500 front drums to inspect and they have all had the tell tale cracks. I recently sold one to another T500 owner, because we both knew about the cracking and my extra wheel had significantly less than his.

One more reason to fit that 4LS from the Buffalo....

tz375 · Post by **tz375** » Fri Dec 11, 2009 3:23 pm

I suspect that if you talk to racers, they "all" know about it but street guys don't see it unless they are picky and they don't push the limits the same way so it really is less of an issue for them.

I first saw it probably 10 years ago and Rick Brekkon was welding them way back then or maybe earlier. It's not a new problem.

It's one of those things that gets re-discovered every couple of years and with more bikes being restored, it's a new wave of owners are finsing this stuff out.

Rustygt550 · Post by **Rustygt550** » Fri Dec 11, 2009 6:11 pm

Thanks guys for the info. I didnt realise it was cracked till i got the hub vapour blasted & polished

TLRam1 · Post by **TLRam1** » Fri Dec 11, 2009 9:03 pm

I need to look at mine, it this something to worry about?

T500 Front hub

T500 Front hub

Re: T500 Front hub