funky pyrotechnics ...
 

  You don't need to be an 'investor' to invest in Singletrack: 6 days left: 95% of target - Find out more

[Closed] funky pyrotechnics when tightening chainring bolts

15 Posts
16 Users
0 Reactions
37 Views
Posts: 966
Free Member
Topic starter
 

the aftermarket anodised chainring bolts on my XT chainset were starting to creak a bit so I decided to check them out.

two are a bit loose, but the other two are pretty firm. they were originally put in with a dab of threadlock.

whilst turning one of the firm ones, there was a bright flash followed by a nice smell of burning... pretty impressive stuff.

has anyone else had this happen?

 
Posted : 07/10/2011 8:45 am
Posts: 0
Free Member
 

😯

Cool, was it flammable lube+heat from pressure?

 
Posted : 07/10/2011 8:49 am
Posts: 0
Full Member
 

do you live in a flinty area? might have been a shard of flint being crushed under pressure.

 
Posted : 07/10/2011 10:08 am
Posts: 22922
Full Member
 

I think you might have got an atom trapped in there and split it. Don't undo the bolt again - all hell will be let loose. Personally I'd been concerned about riding a bike with a broken atom in it, if I were you I'd keep quiet about it and sell it on the classifieds to someone you don't know, preferably a few counties away.

 
Posted : 07/10/2011 10:21 am
 sok
Posts: 0
Full Member
 

I had this tightening up a bolt on my disk brake mount. I almost thought I'd imagined it until I smelt the burning. Very weird I thought.

 
Posted : 07/10/2011 10:24 am
Posts: 17
Free Member
 

Ti bolts, if you have ano ti bolts, often bind and crack with a burning smell. Not sure of the reasoning TBH

 
Posted : 07/10/2011 10:40 am
Posts: 0
Free Member
 

small concentration of magnesium maybe
I think a fair few alloys have magnesium

that is probably complete nonsense though

 
Posted : 07/10/2011 10:43 am
Posts: 0
Free Member
 

Thermite?

 
Posted : 07/10/2011 11:08 am
Posts: 2006
Full Member
 

I had a similar thing when removing a pedal the night before going on a bikey holiday; when the thing eventually came loose it was with an almighty "crack" and the house absolutely stank for ages afterwards!

 
Posted : 07/10/2011 12:55 pm
Posts: 6409
Free Member
 

my kcnc bolts used to do that, the smell was like that from a cap gun

 
Posted : 07/10/2011 1:00 pm
Posts: 0
Free Member
 

why can't all bolts do that? 🙁

 
Posted : 07/10/2011 1:09 pm
Posts: 6
Free Member
 

yep, I've had the same with KCNC chianring bolts.
I assumed they had binded !?!?!?

 
Posted : 07/10/2011 1:46 pm
Posts: 0
Free Member
 

I've had the same with Ti bolts/ ali rings. Small flash and smelt like Nov 5 afterwards.

 
Posted : 07/10/2011 1:48 pm
Posts: 251
Full Member
 

would make a useful alternative to torque settings.

"Tighten until it goes bang"

 
Posted : 07/10/2011 1:49 pm
Posts: 0
Free Member
 

 
Posted : 07/10/2011 1:54 pm
Posts: 9
Free Member
 

wwaswas - Member

would make a useful alternative to torque settings.

"Tighten until it goes bang"


Wrong wrong wrong.
Tighten until it goes bang, then back off 1/8th of a turn.

 
Posted : 07/10/2011 2:31 pm

6 DAYS LEFT
We are currently at 95% of our target!