cabby Posted March 2, 2011 Report Share Posted March 2, 2011 I need to get my head round why the likes of trials UK and others on here state that to calm a bike down, you can DOWN tooth the front sprocket ? Yes, I know there are various other ways also, but specifically this route ? Coming from a road riding perspective, as I do, and fairly new to trials, this flies in the face of what happens with road/track/race bikes. Can anyone give me an explanation to this. Quote Link to comment Share on other sites More sharing options...
bigfoot Posted March 2, 2011 Report Share Posted March 2, 2011 Simple gearing really. A big sprocket give faster acceleration less top speed smaller one less acceleration higher top speed. Quote Link to comment Share on other sites More sharing options...
jimbo349 Posted March 2, 2011 Report Share Posted March 2, 2011 Simple gearing really. A big sprocket give faster acceleration less top speed smaller one less acceleration higher top speed. The op was talking front sprockets not rear Quote Link to comment Share on other sites More sharing options...
totalshell Posted March 2, 2011 Report Share Posted March 2, 2011 whilst i have often lost a tooth or two off the front sproket it certainly doesnt suit all bikes, the beta is fine but do the same to a gasser and it became a wheel lifting thing that kicked me off at will... Quote Link to comment Share on other sites More sharing options...
old trials fanatic Posted March 2, 2011 Report Share Posted March 2, 2011 A smaller front sprocket lowers the gearing which makes the bike less sensitive to a clumsy throttle technique and also effectively shortens the gears. What i mean by that is if you take first gear as an example the bike would be less prone to run away with you if you opened the throttle too quickly. A bit like trying a section in a higher gear means you have to be very precise much more that when pulling a lower gear when you have more time to correct errors. Well thats my take on it although some people will always dissagree with me. 1 Quote Link to comment Share on other sites More sharing options...
bigfoot Posted March 2, 2011 Report Share Posted March 2, 2011 The op was talking front sprockets not rear So was I. Quote Link to comment Share on other sites More sharing options...
cabby Posted March 2, 2011 Author Report Share Posted March 2, 2011 Simple gearing really. A big sprocket give faster acceleration less top speed smaller one less acceleration higher top speed. So was I. OK, what I'm not understanding then is, how come that's the opposite to road bikes ? i.e. smaller front on road bikes for faster acceleration, but smaller on a trials bike gives less acceleration Quote Link to comment Share on other sites More sharing options...
hrc1 Posted March 2, 2011 Report Share Posted March 2, 2011 On really grippy going (remember that?) a lower first gear slows it all down a bit. Gives rider more time..... Also on a GG Pro it brings 4th into play on the hills & snotty going. Like a lot of trials guff - it's just a rider preference, not necessarily right or wrong. Quote Link to comment Share on other sites More sharing options...
broony Posted March 2, 2011 Report Share Posted March 2, 2011 Bigger front or smaller rear sprockets=more speed smaller front or larger rear=less speed sprockets. Most bikes used for road racing are geared down e.g. less teeth on the front or more on the back for better acceleration as most bikes are overgeared for track use. cheers the noo Brian Quote Link to comment Share on other sites More sharing options...
paul w Posted March 2, 2011 Report Share Posted March 2, 2011 theDBF, on your track day bike you could quite easily come down 2 on the front and up 2 on the rear. This normally meant that 1st was useless, but you got to use 4th 5th and maybe even snatch 6th at a push. the general idea was that you kept the motor spinning and every gear change was nearly into maximum power. Thats what you want from a track day bike. Same thing applies on a trials bike, but remember, your rarely on full throttle (or even half) This means that if you do accidentally grab a huge handfull of throttle, it isnt going to accelerate too fast, more revs less speed. I cant remeber what bike youve got? are you trying to back off the power or is this just a hypothetical question? Cheers Paul Quote Link to comment Share on other sites More sharing options...
cabby Posted March 2, 2011 Author Report Share Posted March 2, 2011 theDBF, on your track day bike you could quite easily come down 2 on the front and up 2 on the rear. This normally meant that 1st was useless, but you got to use 4th 5th and maybe even snatch 6th at a push. the general idea was that you kept the motor spinning and every gear change was nearly into maximum power. Thats what you want from a track day bike. Same thing applies on a trials bike, but remember, your rarely on full throttle (or even half) This means that if you do accidentally grab a huge handfull of throttle, it isnt going to accelerate too fast, more revs less speed. I cant remeber what bike youve got? are you trying to back off the power or is this just a hypothetical question? Cheers Paul I'm having a rather healthy debate elsewhere, on another forum, who are all road/track riders, I have said that I have read on here and on Trials UK vids that to calm your bike down, you can go a tooth down, however, they are all disputing this, although none of them are giving a reasoned argument as to why. 1 1 Quote Link to comment Share on other sites More sharing options...
jimmyl Posted March 2, 2011 Report Share Posted March 2, 2011 As said above you can't compare trials with track/road. Most trials bikes are designed with flat torque curves and run on min throttle for a lot of the time. Lowering gearing has no effect on power curves of the engine but gives the rider a fraction more time to react to his/her throttle inputs. Lower gearing will give more torque at the back wheel but is marginal on a low powered trials bike. Lower gearing also reduces the need to have good clutch control which would be required and utilised to good effect by experts on higher geared bikes. Quote Link to comment Share on other sites More sharing options...
b40rt Posted March 2, 2011 Report Share Posted March 2, 2011 The Victor Meldrew of Trials Central. Wow i'm now even less popular than Omar Gadaffi See you have the same taste in head & facial hair wear. Quote Link to comment Share on other sites More sharing options...
gjbiker Posted March 2, 2011 Report Share Posted March 2, 2011 Jump on a mountain bike, preferably a 15 speed or higher and this will help anybody get their head aroung gearing. Small front sprocket and large rear sprocket - pedal like buggery and get nowhere fast. Change to a larger front and smaller rear to achieve maximum speed. Principals remain the same regardless of it being a sports bike or trials bike but the difference in power, torque, speed, gearbox ratios etc will make the feeling of acceleration a totally feeling altogether depending on the variables mentioned. I'm afraid your mates with sports bikes won't be able to relate as well to this as yourself Mr DBF unless of course they've dabbled with a trials bike? Getting the gear ratios right is a very personal thing and two different riders with two different gear ratios on the same type of machine could quite easily result in exactly the same lap times? Horses for courses and all that? Keep up the debate with the roundy roundy racers and point them in the direction of trials - they'll save a fortune! GJ Quote Link to comment Share on other sites More sharing options...
jimmyl Posted March 2, 2011 Report Share Posted March 2, 2011 Another example Take your sports bike buddies out to the car park and set some cones out to ride slalom between. - take your sports bike and try to ride round the cones in first gear and then try it in 2nd. Whats easiest? Quote Link to comment Share on other sites More sharing options...
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