sectionone Posted January 31, 2011 Report Share Posted January 31, 2011 I was doing some traction tests on my trials bike and MX bike in mud and snow in a simple section in my backyard that has an off camber turn, uphill climb and over a log. It's an easy section when dry. When muddy, however, on my trials bike I'll slip on the turn, have no momentum, and spin on the hill without getting enough speed to get over the log. With my MX bike with knobbys, I can track through the turn, carry momentum, accelerate, spin and grab traction to get enough speed to go up the log. As soon as I hit the log with the knobbys, it will slip because of the hard rubber and often I won't make it over. The solution? A butchered trials tire transformed into the ultimate mud tire? It is still in the works but here is what it looks like so far. Trials tire don't work for me in sticky mud because the mud fills up the grooves and making it like a racing slick. Knobbys grab in the mud but the rubber is too hard to wrap around rocks and logs for grip. So how about a trials tire with widely spaced knobs to dig into the mud without clogging up. I know modifying tires is illegal in competition but I'm more interested in getting the best all around traction in muddy conditions. I took my knobby knife and started cutting off half the lugs and am waiting for a good rain to test it out. 1 Quote Link to comment Share on other sites More sharing options...
enrico Posted January 31, 2011 Report Share Posted January 31, 2011 Jeez, that looks like a new tyre that you have 'modified' for your tests??!! Don't tell me it was a brand new tyre - you could have tried it with one of my old ones! I will gladly swap my old ones for some new ones if you wish to carryout further tests on part worn tyres? 1 Quote Link to comment Share on other sites More sharing options...
old trials fanatic Posted January 31, 2011 Report Share Posted January 31, 2011 Ever thought of improving your weight distribution and throttle control?? Dont get the point of practising your lack of riding skills then modifying a tyre which would be illegal anyway to compensate for your shortcomings. Quote Link to comment Share on other sites More sharing options...
pete_scorpa3 Posted January 31, 2011 Report Share Posted January 31, 2011 I suspect the remaining knobbles will wear or even break off really quickly. Not sure what you are hoping to gain rom your experiment unless you ride an awful lot in those type of conditions but not in competition? Quote Link to comment Share on other sites More sharing options...
htrdoug Posted January 31, 2011 Report Share Posted January 31, 2011 (edited) Yikes! but good luck with your experiment! as stated,trials regulations dictate tread pattern for competitions,but for farting around whatever works for you is fine. You might consider sheet metal screws in your knobs(front and rear),works wonderful on logs,not so much on rocks. a little farther north up here we'd put the screws in right after the last hare scramble of the season and just leave them in until the first race of the next,you must use careful throttle control to keep from pitching them out of the rear but they'll let you charge over a log at any angle fearlessly.You do have to retrain after you take them out... Oh yea,make sure you keep your feet on the pegs,once you dab on the trials bike your drive disappears Edited January 31, 2011 by htrdoug Quote Link to comment Share on other sites More sharing options...
tony283 Posted January 31, 2011 Report Share Posted January 31, 2011 A little early for an April fools story ? Never mind it made me laugh and also wince at the waste of a perfectly good hardly used tire which looks like an IRC. Just think how much fuel and riding time you could have had for the cost of butchering what was a perfectly usable tire. If you wish to experiment in the eternal quest for "grip" then first find out what your footprint is for the make of tire that you are using. Many people let their modern tires down too much and with a very soft tire like the IRC the center of the tire will fold in towards the rim instead of providing a flat base like a snowshoe. Now add in personal variables like weight and machine set up and you will eventually come up with the ideal pressure for you and your machine. I'm assuming you are riding a modern bike using the clutch all the time ? Try riding without the clutch and use throttle control instead and now use a blipping technique of on and off to gain momentum between rolling and spinning and flick the bike left and right to get the sidewalls to bite and get extra traction. Tony Quote Link to comment Share on other sites More sharing options...
mattylad Posted January 31, 2011 Report Share Posted January 31, 2011 Also illegal in trials. The tread pattern is fixed, even cutting the front edge back to square makes it illegal as the gap between blocks is bigger Quote Link to comment Share on other sites More sharing options...
sherco29 Posted February 2, 2011 Report Share Posted February 2, 2011 (edited) Experimenting is good! People have been slicing up perfectly good tires about as long as there have been motorcycles! Curious as a trials rookie, how long have we been using the same tread design? Why? Looks just like a tire off a 70's enduro bike (Im sure compounds are MUCH different but the tread sure looks about the same)...surely there is room for improvement? When was the last big tire breakthrough? Don't get me wrong I think they work awesome I run one on my KTM as well! Just that sometimes regulations hold back improvements. Edited February 2, 2011 by sherco29 Quote Link to comment Share on other sites More sharing options...
old trials fanatic Posted February 2, 2011 Report Share Posted February 2, 2011 Experimenting is good! People have been slicing up perfectly good tires about as long as there have been motorcycles! Curious as a trials rookie, how long have we been using the same tread design? Why? Looks just like a tire off a 70's enduro bike (Im sure compounds are MUCH different but the tread sure looks about the same)...surely there is room for improvement? When was the last big tire breakthrough? Don't get me wrong I think they work awesome I run one on my KTM as well! Just that sometimes regulations hold back improvements. They are what they are because that is what the rule book dictates the tread should be. Simple as that! Could improvements be made ? Obviously. Would you be allowed to use them ? Obviously not unless the rule book was changed and that aint gonna happen unless it is to make them grip even LESS which has been proposed. Dont really get your arguement as everybody has to use the same tyre pattern. Just learn to ride your bike if you want more grip. Assuming you ride in competition that is? Quote Link to comment Share on other sites More sharing options...
sherco29 Posted February 4, 2011 Report Share Posted February 4, 2011 I get that we need to all be on the same tread pattern. Just curious how long we have been on it? Since the beginning of Trials? Quote Link to comment Share on other sites More sharing options...
old trials fanatic Posted February 4, 2011 Report Share Posted February 4, 2011 I get that we need to all be on the same tread pattern. Just curious how long we have been on it? Since the beginning of Trials? Pretty close at least since the early sixtys that i know of. Compounds and construction have changed along the way since the God awful Dunlop trials universal and at one point i do remember a return to 350 x 18 rears was suggested as the tyres were getting too good. Perhaps the time has come to look at that again? Quote Link to comment Share on other sites More sharing options...
sherco29 Posted February 5, 2011 Report Share Posted February 5, 2011 (edited) Guessing the rules only cover the tread pattern and not the construction? I know I run a X11 on my KTM 200 as well as running them on the Trials bike...so at least I personally can dig the OP wanting to experiment. Like I said people have been grooving and cutting up new tires for a looooong time! I ran across this vid tonight...really shows the different siping designs and some differences in the knobs. http://vimeo.com/12578353 So ya try it out yet???? Edited February 5, 2011 by sherco29 Quote Link to comment Share on other sites More sharing options...
sectionone Posted March 8, 2011 Author Report Share Posted March 8, 2011 OK, I finally did some thorough testing on my cut up tire. The one in the photo was my ruined IRC that was my first attempt to mount a tubeless. I ruined the bead and it became a victim of the knife. I since bought a new Dunlop 803 and it took only half an hour to cut off half the knobs with my Knobby Knife. I test rode it in ideal traction conditions. Not much difference than a regular tire except on medium to large granite rocks where traction was worse. Good grip on logs. Test ride on rainy day: Mild muddy conditions. Test rode two trials bikes, one with a regular Dunlop, other with a modified Dunlop. Not much difference. Regular tire was better in some cases. I think I made the mistake of too low pressure on the modified tire (3 psi). I upped it to 7 psi for the next test. Test ride on very muddy day: Lots of sticky slop! On inclines, the only way to get traction is with lots of throttle to get the tire spinning to burn through. Regular tire would just spin/go sideways and modified tire was able to get grip. I could get enough momentum with the modified tire to get over the log at the top of the incline while with the regular tire I couldn't. Modified tire was also better in the deep wet sand pit. Results were logical. In sticky mud and deep sand, trials tires grooves clog up and can't get traction. Making more space between knobs lets the tire dig in and clean out better while spinning. I bought a spare rear wheel for quick swapping so my next test will be using a motocross knobby. It should be interesting to combine the low end power of a trials bike with a knobby. The main reason for these test is to get out and ride more. I used to avoid any mud riding but now I look forward to it! 1 Quote Link to comment Share on other sites More sharing options...
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