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Dt125 power valve stick


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Power band " that what its called, :yeah: , you see the old race 2 stroke bikes were like this, [ high cut exhaust port] they had to slip clutch outa the corners and off the line ,[ to stay in the power band,]

Yamaha thought " if we could have a Road bike with the big power band, but it needs to be ridable in town,[ bottom end power]

so they made the P,Valve, the gate closes to give bottom end, YPVS.

Sounds like yours aint opening fully,

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Yeah that's what I think the problem is , when I was out earlier I found slipping the clutch helped at low speeds , she seemed to have plenty of oooosh if I was able to stay in the band (mainly in a straight line haha)

However I would like to use both ends of the scale bottom end and top end so this problem needs sorted, it's frustrating as there isn't any point in doing anything else until I can check the battery,

The question is when I do check the batt should it read 12v? if it's any lower does this mean it needs recharged? Also the batt still has enough power to start the bike so it can't be that low surely??

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A good battery will sit at 12.6 volt roughly, as soon as ignition switched on thers voltage drop. so 12volt aint enuff , that will drop to 11.5v right away,, when recharging it will go up to 13+volts,, whitch is good,,it will settle back to the 12.5 area,

Here . this will do yeh,,, mines is model up about £18.00,

http://www.ebay.co.uk/itm/DIY-DIGITAL-LCD-MULTIMETER-DC-OHM-VOLT-AC-BATTERY-OPERATED-ELECTRIC-METER-13190-/320595309882?pt=UK_BOI_Electrical_Test_Measurement_Equipment_ET&hash=item4aa4f8353a

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Sorry internet slow here didn't realise it would multi post :/

Fixed

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Yeah that's what I think the problem is , when I was out earlier I found slipping the clutch helped at low speeds , she seemed to have plenty of oooosh if I was able to stay in the band (mainly in a straight line haha)

However I would like to use both ends of the scale bottom end and top end so this problem needs sorted, it's frustrating as there isn't any point in doing anything else until I can check the battery,

The question is when I do check the batt should it read 12v? if it's any lower does this mean it needs recharged? Also the batt still has enough power to start the bike so it can't be that low surely??

Fair point. But start at number 1. So many times electrical problems cause greif because people try and cherry pick the fixes.

So start with the battery. And the generator output, should be less than 14v or therabouts at 6k rpm

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A good battery will sit at 12.6 volt roughly, as soon as ignition switched on thers voltage drop. so 12volt aint enuff , that will drop to 11.5v right away,, when recharging it will go up to 13+volts,, whitch is good,,it will settle back to the 12.5 area,

Here . this will do yeh,,, mines is model up about £18.00,

http://www.ebay.co.uk/itm/DIY-DIGITAL-LCD-MULTIMETER-DC-OHM-VOLT-AC-BATTERY-OPERATED-ELECTRIC-METER-13190-/320595309882?pt=UK_BOI_Electrical_Test_Measurement_Equipment_ET&hash=item4aa4f8353a

Very helpful pal Il buy it ASAP , don't have a clue about electrics or batteries but I know a little more now so thanks lad. What battery would you recommend? are these AMG Batts worth it !!

Fixed

Haha I thought the issue was in my end

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Fair point. But start at number 1. So many times electrical problems cause greif because people try and cherry pick the fixes.

So start with the battery. And the generator output, should be less than 14v or therabouts at 6k rpm

Battery issue seems to make sense, but i hope that's it lol How do you measure generator output?

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With the engine running put the meter across the battery.

Then take the revs up to 6 or 7k. Simple. Should stop at 14 and a bit. Dont know the exact number. If there is a problem it will likely hit 20+

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Near enough. So long as the volts hit about 14 quickly and stop your golden.

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Not the battery the generator in the engine produces the high voltage well over 14v in fact the regulator reduces the voltage down to a manageable level, that's why if you regulator goes pop so do your bulbs and wiring. When the power reaches your battery it is enough to charge the battery and run the lights and stuff, to many addons can overwhelm the regulator, that's why it gets hot and burns out, you should check your bikes maximum voltage output before you add any extras like lights or GPS & mobile phones. Hope that helps?

Try this to give you some idea of what happens when your bike is running, not the same as yours but close enough. http://www.electronicamotos.com.ar/technical-resources/library/known-issues/street_65700.html

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Yeh " what he means is engine off , when you put meter on battery , it should be 12.5 volts , and after starting it should read 14+ volts.

:eusa_shifty:

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Cheers again lads, well this morning I woke up to an almighty crash , looked outside and the wind had blown my bike over!!!! It was up against my back door wall with the stand facing outwards and the guests were so strong it's blown over the stand side smashing with left fairing to bits and bending my gear selector inwards ! F****ng fantastic start to the day.

Had a small amount of engine oil on the floor which I hope was coming out of an overflow pipe??? There has been no more leaks since I stood her back up again and I've fired her up all seems well just no more damage has been done

Needless to say her new home is in the kitchen until this ridiculous weather has settled down, hope everyone else's day started better than mine !

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Right the multimeter arrived today! After reading another post about them I set the multimeter to the setting immediately above what I was expecting to get ( so 20v as I was expecting around 12v)

My battery is coming in at 2.93 so I assume that it is pretty much as flat as you can get?? Providing I got the multimeter settings correct???

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