Caswell_35 Posted October 5, 2009 Report Share Posted October 5, 2009 Hi Guys,Iv been playing around with my bike tonight and have noticed that my brake is 'spongy'. When i pull my back brake i can see that my back wheel is moving (when i squeeze hard).Does this always happen? If not does anybody know why it does? and how i can fix it?ThanksCaswell Quote Link to comment Share on other sites More sharing options...
tkD Posted October 5, 2009 Report Share Posted October 5, 2009 Reposition your pads so they're about 2 - 3 mil away from the rim, and tighten your cones, because your wheel shouldn't be moving. Quote Link to comment Share on other sites More sharing options...
Caswell_35 Posted October 5, 2009 Author Report Share Posted October 5, 2009 Hi Guys,Iv been playing around with my bike tonight and have noticed that my brake is 'spongy'. When i pull my back brake i can see that my back wheel is moving (when i squeeze hard).Does this always happen? If not does anybody know why it does? and how i can fix it?ThanksCaswell Sorry i should add im riding a mod!Reposition your pads so they're about 2 - 3 mil away from the rim, and tighten your cones, because your wheel shouldn't be moving.My cones are tight! I mean i could go tighter but i dont think my wheel would move. Also my pads are about 1mm from the rim and my level pulls to about 1 inch from the bar! Far too close for me??? Quote Link to comment Share on other sites More sharing options...
Dan_Trials Posted October 5, 2009 Report Share Posted October 5, 2009 Strip, clean, bleed and adjust. While the pads are off, reface them. Good opertunity to give the rim a fresh grind too. About an hours work and you'd think you had a different bike. Quote Link to comment Share on other sites More sharing options...
Caswell_35 Posted October 5, 2009 Author Report Share Posted October 5, 2009 Strip, clean, bleed and adjust. While the pads are off, reface them. Good opertunity to give the rim a fresh grind too. About an hours work and you'd think you had a different bike.When you say reface them you mean?? sand a fresh face onto them?? which parts are the most important to clean?? Sorry for questions been out of trials for 4 years. Quote Link to comment Share on other sites More sharing options...
Dan_Trials Posted October 5, 2009 Report Share Posted October 5, 2009 Tape some P400 wet and dry to the work bench/ kitchen table/ some thing flat and rub the pad accross it. You just want to remove the layer of glazing that may have formed on them. It might not be necesary but I like to cover everything when I have some thing in bits, no point doing half a job. Quote Link to comment Share on other sites More sharing options...
Ben John-Hynes Posted October 5, 2009 Report Share Posted October 5, 2009 When you say reface them you mean?? sand a fresh face onto them?? which parts are the most important to clean?? Sorry for questions been out of trials for 4 years.Yeah, just sand the surface of the pads. As for the cleaning, you should take the master cylinder out of the lever, clean inside the body and shit, then whack it all back together, and re-bleed. That WILL sort it, because from what you've described, you have air in your brake. Quote Link to comment Share on other sites More sharing options...
Dan_Trials Posted October 5, 2009 Report Share Posted October 5, 2009 Yeah, just sand the surface of the pads. As for the cleaning, you should take the master cylinder out of the lever, clean inside the body and shit, then whack it all back together, and re-bleed. That WILL sort it, because from what you've described, you have air in your brake.Yeah that too, I was only thinking about the slaves ha Quote Link to comment Share on other sites More sharing options...
Caswell_35 Posted October 5, 2009 Author Report Share Posted October 5, 2009 Yeah, just sand the surface of the pads. As for the cleaning, you should take the master cylinder out of the lever, clean inside the body and shit, then whack it all back together, and re-bleed. That WILL sort it, because from what you've described, you have air in your brake.Is it easy to take out? Quote Link to comment Share on other sites More sharing options...
Ben John-Hynes Posted October 5, 2009 Report Share Posted October 5, 2009 Yeah, normally just pop right out. Then just pop back in after. Quote Link to comment Share on other sites More sharing options...
Caswell_35 Posted October 5, 2009 Author Report Share Posted October 5, 2009 Yeah, normally just pop right out. Then just pop back in after.Done all this now, still spongy!! starting to annoy me now!! i will get a fresh grind on tomorrow!! but want it to be more solid!!??Help!!! Quote Link to comment Share on other sites More sharing options...
Dan_Trials Posted October 5, 2009 Report Share Posted October 5, 2009 (edited) Done all this now, still spongy!! starting to annoy me now!! i will get a fresh grind on tomorrow!! but want it to be more solid!!??Help!!!Has the bleed made any difference? You could try a complete fluid flush. What condition was the fluid that came out?Running a brake booster? Edited October 5, 2009 by Dan_Trials Quote Link to comment Share on other sites More sharing options...
ZHI-sam Posted October 5, 2009 Report Share Posted October 5, 2009 (edited) brake booster?edit: dam you bet me to it Edited October 5, 2009 by ZHI-sam Quote Link to comment Share on other sites More sharing options...
Ben John-Hynes Posted October 5, 2009 Report Share Posted October 5, 2009 (edited) You've not bled it right and/or there's a leak in the hose. And make SURE the pads are set up square to the rim.EDIT: You f**kerrs are quick! haha Edited October 5, 2009 by Ben John-Hynes Quote Link to comment Share on other sites More sharing options...
Dan_Trials Posted October 5, 2009 Report Share Posted October 5, 2009 Quote Link to comment Share on other sites More sharing options...
Caswell_35 Posted October 6, 2009 Author Report Share Posted October 6, 2009 Yeh I am running an echo sl booster but I don't think it's making much difference!! Does anyone know why my wheel might bemoving when I pull my brake? Quote Link to comment Share on other sites More sharing options...
terry26rims Posted October 6, 2009 Report Share Posted October 6, 2009 I've tightened my bleed nut in my cylinder before too tight and that allowed my fluid to escape around the nut. Squeeze the lever as tight as possible and check the complete line for drips. Use blue tissue, usually see where it's wet. Quote Link to comment Share on other sites More sharing options...
Steve-A Posted October 6, 2009 Report Share Posted October 6, 2009 Does anyone know why my wheel might be moving when I pull my brake?If you've got air in the slaves/crossover then this could cause the problem. Quote Link to comment Share on other sites More sharing options...
Caswell_35 Posted October 6, 2009 Author Report Share Posted October 6, 2009 I've tightened my bleed nut in my cylinder before too tight and that allowed my fluid to escape around the nut. Squeeze the lever as tight as possible and check the complete line for drips. Use blue tissue, usually see where it's wet.The thing that throws me as it doesnt seem to have a leak!?? just really spongy, I spent all morning bleeding it right through with about 4 syringe worths!! im running a booster and my cones are tight?? its so irritating!Maybe it a flexi rim??If my bads are not level for example one side 1mm away from rim and the other 2mm away will this cause the rim to be pushed across??Caswell Quote Link to comment Share on other sites More sharing options...
ogre Posted October 6, 2009 Report Share Posted October 6, 2009 If my bads are not level for example one side 1mm away from rim and the other 2mm away will this cause the rim to be pushed across??not with a hydraulic, the pressure should always be even Quote Link to comment Share on other sites More sharing options...
Dan_Trials Posted October 6, 2009 Report Share Posted October 6, 2009 Yeah if one pad touches the rim before the other it will keep pushing untill it meets a force greater than it. This is usually the pad on the other side. Have a carefull inspection of it by slowly pulling on the brake a bit at a time and see what is happening. As soon as one pad touches, have a look how far off the other pad is. If there is a gap then alignment is needed. It is still possible for there to be air in the system even if it isn't leaking, although it would have to have been leaking (or incorrectly bled) at some point. When you bled it you did turn the lever so the outlet was at the highest point? Quote Link to comment Share on other sites More sharing options...
Le @ Tnn Engineering Posted October 7, 2009 Report Share Posted October 7, 2009 If your chasing a firm lever feel and want to reduce the flex. It's the whole brake you need to work on.#1 cnc backed pads are stiffer#2 running a booster (but not all booster set ups are created even) Most booster system are the same (long flexy bolts and spacers) #3 Magura clamps that don't use the plastic washers.#4 inbuilt frame boosters are very effective.I'll be releasing a new booster system in about 2 weeks I think you'll like it. Quote Link to comment Share on other sites More sharing options...
Matt Vandart Posted October 7, 2009 Report Share Posted October 7, 2009 If your chasing a firm lever feel and want to reduce the flex. It's the whole brake you need to work on.#1 cnc backed pads are stiffer#2 running a booster (but not all booster set ups are created even) Most booster system are the same (long flexy bolts and spacers) #3 Magura clamps that don't use the plastic washers.#4 inbuilt frame boosters are very effective.I'll be releasing a new booster system in about 2 weeks I think you'll like it.f**k, I have been working on a system like that to go into production in a few months.Looks like you got the jump on me.Ah well great minds think alike and all that.........Matt Quote Link to comment Share on other sites More sharing options...
Caswell_35 Posted October 7, 2009 Author Report Share Posted October 7, 2009 Yeah if one pad touches the rim before the other it will keep pushing untill it meets a force greater than it. This is usually the pad on the other side. Have a carefull inspection of it by slowly pulling on the brake a bit at a time and see what is happening. As soon as one pad touches, have a look how far off the other pad is. If there is a gap then alignment is needed. It is still possible for there to be air in the system even if it isn't leaking, although it would have to have been leaking (or incorrectly bled) at some point. When you bled it you did turn the lever so the outlet was at the highest point?By the outlet you mean? the TPA?? the bit where you adjust the pads from the lever????? Quote Link to comment Share on other sites More sharing options...
Dan_Trials Posted October 7, 2009 Report Share Posted October 7, 2009 By the outlet you mean? the TPA?? the bit where you adjust the pads from the lever?????No, I mean the bit where the fluid comes out when you bleed it. Quote Link to comment Share on other sites More sharing options...
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