little dave Posted June 21, 2009 Share Posted June 21, 2009 on my 1974 dt175 the tach has a marked off area at 7500. unfortunately its faded to pink from the sun. is that where my redline starts or is there some orange area first. right now when i ride, i only take it to just below the "pink line" what is the recommended max rev point? thanks. Link to comment Share on other sites More sharing options...
Moderator Cynic Posted June 21, 2009 Moderator Share Posted June 21, 2009 on my 1974 dt175 the tach has a marked off area at 7500. unfortunately its faded to pink from the sun. is that where my redline starts or is there some orange area first. right now when i ride, i only take it to just below the "pink line" what is the recommended max rev point? thanks. Nope thats it all done at around 7500, the engine ( new) peaked at around 6500rpm with 16bhp. Link to comment Share on other sites More sharing options...
little dave Posted June 21, 2009 Author Share Posted June 21, 2009 Nope thats it all done at around 7500, the engine ( new) peaked at around 6500rpm with 16bhp. thanks cynic. so, it would be ill advised to exceed that point when running thru my lower gears then? (7500?) I understand what you say about it peaking at 6500, as the fastest ive been is 68-70 mph in 5th gear, at 7000. but it seems to still have pull thru first and second above the 7500 line. I have only just noticed this fact last night though so its not a bad habit that i will have to break. I usually shift at around 7k. Link to comment Share on other sites More sharing options...
Moderator Cynic Posted June 21, 2009 Moderator Share Posted June 21, 2009 thanks cynic. so, it would be ill advised to exceed that point when running thru my lower gears then? (7500?) I understand what you say about it peaking at 6500, as the fastest ive been is 68-70 mph in 5th gear, at 7000. but it seems to still have pull thru first and second above the 7500 line. I have only just noticed this fact last night though so its not a bad habit that i will have to break. I usually shift at around 7k. The engine will still be making power past 6500 but in decreasing amounts and the stress on an engine is the square of engine speed. So at 4000 rpm you have 16 times the stresses compared to 1000rpm, if we take it further 7000 rpm is fifty times the stress of 1000 rpm, 8000 would be 64 times the stress. These are hardly scientific but you get the idea. Link to comment Share on other sites More sharing options...
Moderator drewpy Posted June 21, 2009 Moderator Share Posted June 21, 2009 took my xs400 over to 10k today, it red lines at 9k whoops!!! Link to comment Share on other sites More sharing options...
wild foamy Posted June 21, 2009 Share Posted June 21, 2009 my DT doesnt have a redline... Woohooo!!!! Jawa redlines at 5750... but fair amount of grunt to it, managed to powerslide and spit me off into the garden hedge yesterday :\ Link to comment Share on other sites More sharing options...
Moderator drewpy Posted June 21, 2009 Moderator Share Posted June 21, 2009 my DT doesnt have a redline... Woohooo!!!! Jawa redlines at 5750... but fair amount of grunt to it, managed to powerslide and spit me off into the garden hedge yesterday :\ got a video?, especially in punjab Link to comment Share on other sites More sharing options...
wild foamy Posted June 21, 2009 Share Posted June 21, 2009 got a video?, especially in punjab nope, my dad was getting the washing in off the line because he didnt want it stinknig of two stroke oil, there i was making cropcircles in the garden and got a bit too confident with the throttle, back end slipped out and next thing i know the bike is down and im in the hedgerow :\. my dad laughed and said "whyd' you throw it down?, dont you like it?" Link to comment Share on other sites More sharing options...
Rapco Posted June 28, 2009 Share Posted June 28, 2009 The engine will still be making power past 6500 but in decreasing amounts and the stress on an engine is the square of engine speed. So at 4000 rpm you have 16 times the stresses compared to 1000rpm, if we take it further 7000 rpm is fifty times the stress of 1000 rpm, 8000 would be 64 times the stress. These are hardly scientific but you get the idea. hmmm, i think this is wrong. The stress on the engine depends mostly of how much you open the throttle. Meaning if you are wot at 6500 and at 10 000, the stress on the engine is pretty much the same. The stress would be different is you would stay steady at those rpm, then this would mean you would be half throttle to stay at 6500 and 3/4 to be at 10000. maybe the stress would be even harder at wot at low rpm, since the engine is have more pressure to push. Thats what at think. but it sure is true that reving hard the engine will put stress on it. correct me if im wrong. Link to comment Share on other sites More sharing options...
Moderator Cynic Posted June 30, 2009 Moderator Share Posted June 30, 2009 hmmm, i think this is wrong. The stress on the engine depends mostly of how much you open the throttle. Meaning if you are wot at 6500 and at 10 000, the stress on the engine is pretty much the same. The stress would be different is you would stay steady at those rpm, then this would mean you would be half throttle to stay at 6500 and 3/4 to be at 10000. maybe the stress would be even harder at wot at low rpm, since the engine is have more pressure to push. Thats what at think. but it sure is true that reving hard the engine will put stress on it. correct me if im wrong. Nope your on about torque, i'm talking about no load situation. The loads you are talking about are IN ADDITION to the basic stresses. Link to comment Share on other sites More sharing options...
Recommended Posts