trials_pimp Posted January 18, 2008 Report Share Posted January 18, 2008 I would like to know the Correct torque setting for my rear Brake Mounts.If it makes the difference:GU Frame4 Bolt Magura MountsEcho 4 Bolt Booster.I dont want to hear "just do it until it feels right" any sped can do that. I want to know the correct Torque setting for the rear brakes. Quote Link to comment Share on other sites More sharing options...
dave85 Posted January 18, 2008 Report Share Posted January 18, 2008 4.5 Nm is recommended for the top screws in a evo mount, as all four bolts in a trials set-up do the same job I would follow that.I would disagree with your reasoning though, any numpty can (and at my last place, did) follow a torque setting and f**k things up. "Just do it till it feels right" is a better way all round. It's not as though you're sending the bolts seriously towards their elastic limit and are worried about stretching. Quote Link to comment Share on other sites More sharing options...
Endohopper Posted January 18, 2008 Report Share Posted January 18, 2008 Google's not terribly helpful for this particular question , however THIS CHART might help give you a ballpark figure . Quote Link to comment Share on other sites More sharing options...
2sixstreet Posted January 18, 2008 Report Share Posted January 18, 2008 Google's not terribly helpful for this particular question , however THIS CHART might help give you a ballpark figure .Is that chart assuming the material for the bolt and what you're screwing into are the same. Doesn't make a lot of sense unless i'm missing something. No offense to Endo but I think the majority of people are screwing a steel bolt into an aluminium frame which doesnt seem to be mentioned.I agree with dave85. If you're worried about it stripping dont do it up as much. If you're worried about it coming undone check it regularly and do it up a bit tighter next time. It also helps if you do each side of the clamp up evenly, not one side fully and then the other.If you're running a booster with spacers then you will have no problem with it coming loose with lowish torque. A bolt works by stretching so the longer the better and the harder it is to come loose by itself. Quote Link to comment Share on other sites More sharing options...
Endohopper Posted January 18, 2008 Report Share Posted January 18, 2008 ... screwing a steel bolt into an aluminium frame which doesnt seem to be mentioned...Whoops , :$ Didn't occur to me . That said , the frame may well be aluminium , but I suspect that brake posts / mounts are usually steel ? Quote Link to comment Share on other sites More sharing options...
trials_pimp Posted January 18, 2008 Author Report Share Posted January 18, 2008 I was intriqued to know as just rebuilt my new brake, and seeing as I have the facilites I thought it wise to use them.But if there is no specified torque Ill Use the engineers elbow.Im suprised no manufacture has released a setting, would help alot in a court case should something go wrong and the rider try to sue the company (not that many would) Quote Link to comment Share on other sites More sharing options...
psycholist Posted January 18, 2008 Report Share Posted January 18, 2008 (edited) Most of the 4 bolt mounts in trials frames are aluminium. Generally once you have 5 or 6 turns of good thread engagement, about 1/4 to 1/2 turn past what you can tighten it to using the short end of the allen key for leverage should be fine as a starting point. If you do strip a thread it's not the end of the world anyway. Helicoils are your friend . Also grease the bolt threads and under the bolt head before installing it so that frame friction isn't contributing disproportionately to resist the torque you're tightening the bolt with. The grease will also help stop the parts seizing together, not an uncommon problem with steel bolts in AL...The table linked up is for US customary sized bolts. All the bolts on bicycles are metric (Thankfully)... Edited January 18, 2008 by psycholist Quote Link to comment Share on other sites More sharing options...
Phil H Posted January 19, 2008 Report Share Posted January 19, 2008 I don't think it's really a big deal.The main reason your going to de-thread it is by cross threading I would think so try spraying abit of silicon spray in before you fit the maggy, works a beauty and makes it easier to tell when its tight due to the low friction Phil Quote Link to comment Share on other sites More sharing options...
Captain Scarlet Posted January 19, 2008 Report Share Posted January 19, 2008 (edited) My advice if its an alumminum thread.Overtighten them, strip the threads, and helicoil them.Helicoils are the dogs. Edited January 19, 2008 by Fugley Quote Link to comment Share on other sites More sharing options...
Tom_ Posted January 19, 2008 Report Share Posted January 19, 2008 my echo cnc mounts do up till the two halves touch. seems to do the job and never stripped anything.... Quote Link to comment Share on other sites More sharing options...
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