TomB Posted November 8, 2009 Share Posted November 8, 2009 Apparently West London Yamaha have pioneered a way to "de-restrict" the YZF R125, and are charging £150+vat to do it. It consists of fitting a specially modified secret part and a new sprocket, Now common theory is the bike is not restricted any way, so firstly I imagine this is tuning. The second thing is there is supposed to be an article by Liam from MCN floating around somewhere, where he had the work done... I cant find this and wanna see what he had to say. I just dont seem entirely convinced, expecially as they claim that you dont need any kind of fuel management system fitting. Can anyone shed any light on this as I am having real trouble finding anything out! Thanks Link to comment Share on other sites More sharing options...
stinger_ YZF r125 Posted December 16, 2009 Share Posted December 16, 2009 right then, the bike is resricted from word go. to derescrict the bike you do not do anything with the rear spocket or the front, all this will do is change the accelaration. the bike is resricted in the exhuast pipe, if you knock the baffels out it will be abit quicker and loader. or you could do it properly by buyin a chip for £5.00 off yamamha with cancles out the rev clock and will allow to rev way past 12rmp. but a full scoirpan or lavinchy pipe, ur bike will then be de-restricted..... the best thing to do would be wait till new year now if you havnt allready done anything about it, i say this because mosati have made a 192cc big bore for this modle of bike with a pipe and crank shaft to match in suit. do not do anything with the spocket Link to comment Share on other sites More sharing options...
wizz1978 Posted December 9, 2010 Share Posted December 9, 2010 right then, the bike is resricted from word go. to derescrict the bike you do not do anything with the rear spocket or the front, all this will do is change the accelaration. the bike is resricted in the exhuast pipe, if you knock the baffels out it will be abit quicker and loader. or you could do it properly by buyin a chip for £5.00 off yamamha with cancles out the rev clock and will allow to rev way past 12rmp. but a full scoirpan or lavinchy pipe, ur bike will then be de-restricted..... the best thing to do would be wait till new year now if you havnt allready done anything about it, i say this because mosati have made a 192cc big bore for this modle of bike with a pipe and crank shaft to match in suit. do not do anything with the spocket hello mate i have just joined the owners club and have owned my yzfr125 for a year now and love it but it does need more poke this 192 big bore kit sounds just the thing do you have any idea how much it will be and when next year it will be available Link to comment Share on other sites More sharing options...
Paulwhite Posted December 9, 2010 Share Posted December 9, 2010 its a 125 4 stroke! its not restricted. everything is the way it is to give you the best balance between performance and reliability if you change the exhaust then it will make it flow a little better but its injection so the icu/ecu/cdi or whatever you call it will be out of sync with the engine. the "secret modified part" is most likely either a re-profiled cam or a ecu chip which will give you better performance at a cost! and the cost 9 times out of 10 is reliability! plus any addition or modification done to the bike which has not been done by yamaha will void warranty! best thing (and the cheapest) is change the sprocket size, that way your not messing with the balance of the engine and you can set it for more speed or more acceleration at the expense of the other (more speed = less acceleration and visa versa)im sure ppl wouldnt mind dropping a second at pull-off to gain an extra 10mph. as to the 192 big bore kit, it would dramatically improve the top speed and acceleration but think of how much extra force is going into the crank and bearings!(it was designed and built as a 125cc!) could find you need a new engine after a year or two. plus if ur on L plates and happen to get randomly pulled by a copper that knows a little about bikes ...well lets just say you wont be riding it home. sorry for the rant lol but if you want to go fast on a 125 sell the r125 and get a 2 stroke (as it will work out allot cheaper to go faster!) Link to comment Share on other sites More sharing options...
Moderator Airhead Posted December 9, 2010 Moderator Share Posted December 9, 2010 Talking of 'Restricted' are YOU restricted? or have you passed your test, Learners can only ride 125's (I suppose you already know this though) Link to comment Share on other sites More sharing options...
Moderator Cynic Posted December 9, 2010 Moderator Share Posted December 9, 2010 its a 125 4 stroke! its not restricted. everything is the way it is to give you the best balance between performance and reliability if you change the exhaust then it will make it flow a little better but its injection so the icu/ecu/cdi or whatever you call it will be out of sync with the engine. the "secret modified part" is most likely either a re-profiled cam or a ecu chip which will give you better performance at a cost! and the cost 9 times out of 10 is reliability! plus any addition or modification done to the bike which has not been done by yamaha will void warranty! best thing (and the cheapest) is change the sprocket size, that way your not messing with the balance of the engine and you can set it for more speed or more acceleration at the expense of the other (more speed = less acceleration and visa versa)im sure ppl wouldnt mind dropping a second at pull-off to gain an extra 10mph. as to the 192 big bore kit, it would dramatically improve the top speed and acceleration but think of how much extra force is going into the crank and bearings!(it was designed and built as a 125cc!) could find you need a new engine after a year or two. plus if ur on L plates and happen to get randomly pulled by a copper that knows a little about bikes ...well lets just say you wont be riding it home. sorry for the rant lol but if you want to go fast on a 125 sell the r125 and get a 2 stroke (as it will work out allot cheaper to go faster!) This advice from someone trying to construct a ram air/positive pressure system for a 125 Link to comment Share on other sites More sharing options...
Paulwhite Posted December 9, 2010 Share Posted December 9, 2010 This advice from someone trying to construct a ram air/positive pressure system for a 125 cheeky so n so! its not a ram air positive pressure system its just a air box replacement! no harm in havin a play Link to comment Share on other sites More sharing options...
up.yours Posted December 9, 2010 Share Posted December 9, 2010 it seems that your not too bothered about breaking the Law. sooo , buy a Z1000 if you want a bit more poke,and fuck em.... 1 Link to comment Share on other sites More sharing options...
ChristianSRA Posted January 3, 2011 Share Posted January 3, 2011 it seems that your not too bothered about breaking the Law. sooo , buy a Z1000 if you want a bit more poke,and fuck em.... I'm not to sure if that's going to go down too well. We all know a S1000RR would please the police more Link to comment Share on other sites More sharing options...
Kyle shepherd Posted January 26, 2014 Share Posted January 26, 2014 Alryt guys/girls I have just joined and would really like two no what all I need two get if I am putting in a 182cc big bore kit two my yzf r125 Link to comment Share on other sites More sharing options...
pilninggas Posted January 30, 2014 Share Posted January 30, 2014 Alryt guys/girls I have just joined and would really like two no what all I need two get if I am putting in a 182cc big bore kit two my yzf r125 You might want to introduce yourself in the new members area - we will help if we can, but's good manners. The general mood of the yzf125r owners is that the big bore kits are quite a bit of hassle for limited return. From memory, you'd need: athena barrel and piston. a bigger injector (or multihole) a fuelling mod. some of these guys have spent £hundreds for maybe 2bhp more. Spend the money on better gear, training or some long distance trips. Link to comment Share on other sites More sharing options...
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