zippy Posted October 19, 2007 Report Share Posted October 19, 2007 I had at one time seen a web site that explained in great detail how to drill holes in the brake discs for a 2000 Sherco. After much google searching I am unable to find it. I think it may have been an Australian site. If anyone knows the site I am looking for any info would be greatly appreciated. Quote Link to comment Share on other sites More sharing options...
ham2 Posted October 19, 2007 Report Share Posted October 19, 2007 I was at the same point as you..ready to drill..but everyone I spoke to said not to do it(reduced contact area or something??). If you look around at Gassers and Montesas you can see more holes than disc !! Sorry I can't be any help. Anyone out there? Quote Link to comment Share on other sites More sharing options...
baldilocks Posted October 20, 2007 Report Share Posted October 20, 2007 I think the gas gas and monts have shapes machined out rather than holes. The shapes act a little like a wavy disc so that the pad is always biting on an edge rather than a smooth surface. I dont think you will get the same effect from just drilling holes but you could just buy a disc of another make of bike as all the hubs are AJP anyway. I have seen Shercos with Beta front discs fitted. Quote Link to comment Share on other sites More sharing options...
zippy Posted October 21, 2007 Author Report Share Posted October 21, 2007 I am thinking of going with a new 4-piston caliper. More oomph! me thinks. and keeping the old disc. Thanks for all the replies. Quote Link to comment Share on other sites More sharing options...
ned1 Posted October 21, 2007 Report Share Posted October 21, 2007 I think the gas gas and monts have shapes machined out rather than holes.The shapes act a little like a wavy disc so that the pad is always biting on an edge rather than a smooth surface. I dont think you will get the same effect from just drilling holes but you could just buy a disc of another make of bike as all the hubs are AJP anyway. I have seen Shercos with Beta front discs fitted. what? you do realise that the discs are flat and there is no edge for them to bite on? Quote Link to comment Share on other sites More sharing options...
baldilocks Posted October 21, 2007 Report Share Posted October 21, 2007 I think the gas gas and monts have shapes machined out rather than holes.The shapes act a little like a wavy disc so that the pad is always biting on an edge rather than a smooth surface. I dont think you will get the same effect from just drilling holes but you could just buy a disc of another make of bike as all the hubs are AJP anyway. I have seen Shercos with Beta front discs fitted. what? you do realise that the discs are flat and there is no edge for them to bite on? grip a Gas Gas or mont disc between finger and thumb and slowly spin the wheel until you find the edge, yes the disc is flat but the large cutaway creates an effect like an edge as it passes through the pads. then report to detention to write up your findings Quote Link to comment Share on other sites More sharing options...
ned1 Posted October 23, 2007 Report Share Posted October 23, 2007 my findings are, the discs are pefectly flat, unless the pads, move into the grooves, which iof you think about it can't really happen because they are usually the same height as the disc or there abouts, you can feel the edges because your fingers sing into the grooves. Quote Link to comment Share on other sites More sharing options...
barrybaines Posted October 23, 2007 Report Share Posted October 23, 2007 Baldi is correct I think you will find. Not only there to look pretty but less weight, clears crap off the pads keeping them fresh, less heat in the system etc etc. Even scoring the disks Ala the old RGV250 front discs would have the same effect to a degree well at least they could get a little more traction and keep the pads fresh. Although doing the job sounds more hassle than it's worth what with having to heat treat/anneal the rotors again. Be much better off buying some different rotors as previously suggested. Quote Link to comment Share on other sites More sharing options...
ned1 Posted October 23, 2007 Report Share Posted October 23, 2007 (edited) well according to you he isn't you are saying that the discs with the holes in keep the discs cooler, keep the pads clean and are lighter. All these points are correct fair enough, although what baldi is saying, is that becuase the discs have holes, the pads grip to the disc more, which is actually not true, the discs are completely flat, put them on a surface plate and you will see, scoring the discs will help the brakes because you are causing more friction, although this will wear your pads down more quickly. So really scoring the discs and putting holes in them will do the same thing, although in different ways. Disc with holes will stay cooler and the pads will stay cleaner, scored discs will bite more because they will will create more friction with the pads. In theory a disc with no holes should perform better because there is more surface area for the pads to grip to, although with heat and water etc. drilled discs are better. Edited October 23, 2007 by ned1 Quote Link to comment Share on other sites More sharing options...
barrybaines Posted October 23, 2007 Report Share Posted October 23, 2007 Keeping the pads clean and having an edge for the pads to bite on to me mean one and the same thing? scoring the disks and having holes in them also mean one and the same? only downfall of scoring is you don't get the same heat dissapation that you would with drilling. I agree that you don't have the same surface area to brake on and you may even find the later disks that are drilled MAY even be slightly larger? (only a geuss) And you are right the pads wont last as long but this is were you need to weigh up whether better brakes are worth the extra Quote Link to comment Share on other sites More sharing options...
baldilocks Posted October 23, 2007 Report Share Posted October 23, 2007 (edited) Ned heres another experiment for you. find someone with an 07 sherco with wavy discs, under light braking you can feel a slight pulsing on the lever as the disc rotates. This I think is the effect of the reduced circumference part in the outside edge of the disc passing through the pads. Although the disc is flat the pressure applied must force the top edge of the pad to close when the reduced circumference passes through and the disc will then force the pad apart again as the wider (greater circumference not disc width) part passes through the pads. now do the same thing on a 4rt and you get the same pulsing effect. except the 4rt has cutaways, its not a wavy disc. I'm quite happy to admit I'm wrong if you can explain the above, its just my theory that the cutaways act like an edge on a wavy disc. cheers Edited October 23, 2007 by Baldilocks Quote Link to comment Share on other sites More sharing options...
biffsgasgas Posted October 23, 2007 Report Share Posted October 23, 2007 I am not telling you either of you are wrong <disclaimer I would like to say that i ride with zippy virtually weekly and regardless of what brakes he has its not going to help much. He seems to have an alternate gravitational force which attracts them to trees rocks mud any other various obsticals found in nature. To be honest guys i love the conflict but if its zippy your argueing about then you might want to come ride with us to see for yourself. He tends to use his feet a lot. --Biff Quote Link to comment Share on other sites More sharing options...
ned1 Posted October 23, 2007 Report Share Posted October 23, 2007 (edited) oreet bladi iv had a reet good think about it, maybe the pads like sink if you like slightly into the grooves on the disc, so maybe the cut outs do act like an edge. It's just i can't relly see how metal could do this, although i suppose with all the pressure from the brake maybe it does. i've just had another thought, what about mybe if the pistons in the brake are offset slightly, so that the front of the pad hits the disc first slightly, so that they dig into the grooves if you like although this would make the pads wear unevenly. hmmmm i'm not too sure now lol ! Edited October 23, 2007 by ned1 Quote Link to comment Share on other sites More sharing options...
zippy Posted October 23, 2007 Author Report Share Posted October 23, 2007 OK maybe I should have explained this first off, BIFF, I have an alergy to my footpegs OK, I am looking into medication for this, I think a beer a lap has been suggested. As far as the attraction to trees, ground, mud, and rocks.....what can I say nature just loves me. as far as my front brake goes, I am looking for better braking performance. I have done the following to the brake: new pads took apart caliper and pistons cleaned everything bled brakes well rebuilt master cylinder My problem is that I pull in front brake lever and get pressure on disk, and it is progressive to a point. pull lever = more pressure but at about half way pull lever more = same pressure and it is just not enough. Biff has ridden my bike and he can back me up on the performance of my front brake. On the flip side Biff's bike I can use 1 finger going down hill and stop on a dime, my bike 2 fingers and sqeeze hell out of it and still bypass the stupid marker on the tree that I am supposed to turn around and collect my 5 (again) I have decided to do the following: buy a 4-piston caliper (more disk area being squeezed and more pressure?) buy new brake line (possible weak spot in old one) Quote Link to comment Share on other sites More sharing options...
copemech Posted October 23, 2007 Report Share Posted October 23, 2007 Zipper, You need to shock it. Quote Link to comment Share on other sites More sharing options...
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