Daniel Cooper Posted August 25, 2009 Share Posted August 25, 2009 had a go on an older 1990 dtr with an engine and plastics off a 2003 model few weeks ago, took it for a spin and noticed when it was in gear at times i would pin the throttle and sometimes it would just continue going as it was or the engine would pick up very slowly but when it hits higher revs it revved freely and when clutch was held in it revved freely again, what could cause this cause ive never rode a dt before but am interested in this bike Link to comment Share on other sites More sharing options...
Moderator Cynic Posted August 25, 2009 Moderator Share Posted August 25, 2009 had a go on an older 1990 dtr with an engine and plastics off a 2003 model few weeks ago, took it for a spin and noticed when it was in gear at times i would pin the throttle and sometimes it would just continue going as it was or the engine would pick up very slowly but when it hits higher revs it revved freely and when clutch was held in it revved freely again, what could cause this cause ive never rode a dt before but am interested in this bike Its just what baby 2 strokes do. They make power at high RPM. I've just got a TDR250, 2stroke 250 twin and that is flat untill 6000RPM whereby it goes psyco, the DT will be very similar just with less psyco. Link to comment Share on other sites More sharing options...
Daniel Cooper Posted August 25, 2009 Author Share Posted August 25, 2009 ohh i see, im more used 2 off road 4strokes, it had standard pipe on but comes with dep pipe so that myt free it up aswell? Link to comment Share on other sites More sharing options...
Moderator Cynic Posted August 25, 2009 Moderator Share Posted August 25, 2009 ohh i see, im more used 2 off road 4strokes, it had standard pipe on but comes with dep pipe so that myt free it up aswell? Ahh the mist clears, off road 4 strokes are specifically designed to give you loads of low down stomp. The smoker will seem flat to one of those the off road stuff wont be restricted either. The dep pipe may make a diference if its the complete system but it will only push the power further up, the tailpipe will just make it noisy so you THINK its quicker . Bloody good service and de-coke will probably get more go than the pipe. Check the powervalve, it may not be connected up as the engine is in an older chassis. Look on the LH side of the barrel is there a round casting with a couple of cables going into the top? Link to comment Share on other sites More sharing options...
bob-c Posted August 26, 2009 Share Posted August 26, 2009 [Check the powervalve, it may not be connected up as the engine is in an older chassis. Look on the LH side of the barrel is there a round casting with a couple of cables going into the top? This may well be the problem , the powervalve if not working may be in the open position which gives you all top end power, sod all till 6000rpm Do a search on powervalve or ypvs to get the lowdown on cleaning and adjustment , on the 1988 DT200 I picked up cheap the cables were broken . then the servo operating the cables went . Replaced adjusted and cleaned everything and there is now plenty of power through the rev range . I'll try and dig out the links I found if you get stuck .try here http://www.yamahait.com.au/forum/index.php Bob Link to comment Share on other sites More sharing options...
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