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DR250 6v or 12v?

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I'm having trouble starting my 1992ish model from cold. It's kick start only with no battery. I've got the carb set up right now using a colourtune kit and I'm satisfied the is fuel getting through and the choke works. (Carb overhauled, cleaned and new diaphragm). I've pulled the plug and the spark looks weak even with a new plug. The compression feels good but I haven't measured it.

When it's running it's only putting out 2.6vdc on tickover and the 3 yellow wires from the mag are showing 2.6vac between each pair. The dc voltage rises to around 5 or 6vdc at half throttle and above half throttle the meter won't read a steady voltage (numbers jump around everywhere).

I'm guessing that the weak spark on kickover is because at the speed of kickover I'm only generating a low voltage.

My question is this: Do those figures seem correct? I assumed it was a 12v bike and the reg/rec would trim the a.c. voltage to dc but the only steady reading I've been able to achieve is 6vdc. 

My coil meters out ok (16.25kohm and 0.9ohm) do I was going to replace the reg/rec next, but now I'm not sure because if the reg rec is only getting 2.6vac to start with maybe the magneto needs looking at?

All help appreciated 

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This is for a DR250/350 90-94 US & UK models

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Maybe grab the proper wokshop manual for it

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If I knew what model it was I would. 

That page is from the clymer manual which I have already but none of the wiring diagrams in the clymer manual match my components (10 wires on the cdi and 5 on the reg rec). I can't find those particular parts in any diagram online either so that's why I was questioning whether this model  was even supposed to be a 12v in the first place. I didn't want to be throwing money at it trying to get 12v by replacing the magneto etc only to find out that those particular components only run on 6v

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Got similar issues with a '92 DR250s I picked up Friday.  Seller said carb probably needed cleaning but I suspect low voltage problem.  Very weak spark.  Are these bikes prone to ignition issues.  I was going to look at the coil next.

 

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Warm coil up and then measure resistance (if you can't start it warm it with a hairdryer) Should be about 12k ohms to 20k ohms between the plug cap and the earth bolt, and about 0.6 to 1 ohm between the earth bolt and the trigger tab. 

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Finally got some life out of my 250.  Started and died.  Still looking at ignition.  Had to order a plug for it.  Wanted to go with a non-resistor type and none of the parts houses carry them in stock.  Will get it today and see if that helps with cold start.

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Let us know how you get on.

I've ordered an aftermarket coil that supposedly gives 34% more spark but I'm sceptical.

I'm taking a look at my flywheel tomorrow as I'm starting to suspect there may be an issue there

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Well the non-resistor plug did the trick.  Got it started.  Would only run on full choke so I blocked off the vacuum line going to the petcock.  Thinking about changing that out anyway.  The diaphragm doesn't work.  Fuel flows regardless.  Anyway, the more I ran it the more it settled down and was finally able to get it off choke but only at high(3000rpm) idle.  Rode it around the place a little before dark.  Will continue to mess with it.  Will probably take the carb off again and remove the factory plug so I can adjust the fuel needle and see if I can tune it.

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