2 easy questions

BG2000

I always thought that Schraeder valve tubes were cheap, but I've just got some lovely new wheels with EX729 rims, and they're drilled for Shraeder.

Q: So are shraeder valve tubes cool again ? Are they any good compared to presta ?

2nd question. I fitted new XT rotors to new Mavic wheels 1 1/2 years ago using new XT bolts without any grease. They had just the blue threadlock compound on them.

I've just tried to remove the rotors to refit them onto my new wheels and almost all the rotor bolt head torx sockets (caps) are rounding off. I've tried different torx tools, just to make sure it's not a problem with my tools. I've even fitted a professional torx head to an impact driver, and even that couldn't remove 2 out of the 6 on my front wheel. I'm now resorting to hacksawing a slot into the bolts, and using the flathead bit in my impact driver.

Q: Was I supposed to apply grease to these bolts ? What have I done wrong ?

nicklouse

1 makes no difference.

2 No.

Ps a better topic heading would have been an idea.

BG2000

nicklouse wrote:

Ps a better topic heading would have been an idea.

Sorry, I'm not sure why I chose that ? :?

Do you know what I may have done wrong with my rotor bolts? I just want to make sure this doesn't happen again. I always avoid placing oil/greas anywhere near the rotors, as it can spread itself over time.

Are Shimano bolts renowned for poor quality ?

glauciaregina9

1. Presta vs Scrader: pretty much irrelevant, particularly on an MTB.

Presta are (apparently) better for the silly-high pressures of a road bike, and the slimmer valve is better suited to narrower rims as a smaller hole is required


2. Blimmin' annoying isn't it.

Whether you're "supposed to" or not, I now always grease my disc rotor bolts after suffering exactly the same situation you're in now..

I filed opposite sides of the bolt heads flat so I could get a small spanner on them to loosen them off. Scratched the braking surface of the disc a bit, but not enough to be a problem.

mrfmilo

All rotor bolts are pretty much the same, (unless you go for Ti) so I wouldn't think it's the bolt (s) that was the problem. You probably overtightened them, I've over tightened some before and they stripped upon removal. :P Don't go crazy tight, just keep them snug.

glauciaregina9

p.s.

I've never had any issues with grease from the rotor bolts migrating onto the braking surface, or anywhere else it shouldn't be... you only need to use a tiny amount.

I would definitely use grease and not oil though.

Rockhopper

Sounds like the threadlock on the bolts did the job then
The trick is to use a bit of heat on them to break the threadlock then try and get them out.