DR350 Thread

[mouthfulloflake]

I had forgotten its an enrichment circuit and not a choke flap

I think bender is on it.

thats pretty much the only way for it to be so rich if the jets are in fact screwed into place in the carb body, and the needle is in fact not being prevented from dropping down all the way for some reason.

[RuggedExposure]

Originally Posted by mouthfulloflake

I had forgotten its an enrichment circuit and not a choke flap

I think bender is on it.

thats pretty much the only way for it to be so rich if the jets are in fact screwed into place in the carb body, and the needle is in fact not being prevented from dropping down all the way for some reason.

I meticulously reassembled the carb, and cleaned every jet, orifice, nook, cranny, hole, and surface.
Installed it on the bike, and it fired up immediately.
Idled fine with the choke pulled out, warmed up nicely.
Took it for a spin, and right away it began getting flooded again...

Before it had a chance to cool I yanked the carb off. once again the intake was wet with fuel, and smoke poured out of the intake.

I decided to give the carb a sort of bench test by hooking it up to the tank but leaving it off the bike so I could see what it is doing.

Hooked the fuel line up, turned on the gas, the float bowl filled and that was it. No gas came pouring out as expected, the bowl didn't overfill... So I turned the cable assembly to simulate some throttle. The pumper squirted a fair amount of gas out and that was it. I wonder if the fuel I'm finding in the intake is just from the pumper and my problem is an electrical gremlin???

[Greg Bender]

Originally Posted by RuggedExposure

I meticulously reassembled the carb, and cleaned every jet, orifice, nook, cranny, hole, and surface.
Installed it on the bike, and it fired up immediately.
Idled fine with the choke pulled out, warmed up nicely.
Took it for a spin, and right away it began getting flooded again...

Before it had a chance to cool I yanked the carb off. once again the intake was wet with fuel, and smoke poured out of the intake.

I decided to give the carb a sort of bench test by hooking it up to the tank but leaving it off the bike so I could see what it is doing.

Hooked the fuel line up, turned on the gas, the float bowl filled and that was it. No gas came pouring out as expected, the bowl didn't overfill... So I turned the cable assembly to simulate some throttle. The pumper squirted a fair amount of gas out and that was it. I wonder if the fuel I'm finding in the intake is just from the pumper and my problem is an electrical gremlin???

Spark plug cap?

[BigD_83]

Having read through the posts, this certainly makes me think it is a timing/weak spark issue rather than carburation. I've seen this happen with some of my other bikes, but not to the extent you are describing. In one case it was a bad coil, another was bad spark plug leads.

There are plenty of cases of coils/CDIs/ignitors failing when hot, at least in the Suzuki GS and Honda CB world.

I'm new to the DR game, but thought I'd throw my point of view out there. I hope I can learn something from this for when I finally pick up my DR 350/450 setup similarly to yours.

[Wadester]

Don't know if this would help diagnose your issue - but a trick I used to use back in automechanic days for finding a miss/bad spark wire/plug would be to use an inductive pickup timing light. It can tell you if and when you're getting spark, since the inductive pickup only "fires" if there is enough electricity flowing. That would show you if the spark was failing when it was running bad.
Biggest problem is that you also have to pull the trigger on mine. If you have to be moving (under load) for it to happen, you'd have to secure the timing light and strap down the trigger (and the excess lead wires of the TL).

[RuggedExposure]

ok, lets sum things up:

Bike ran perfect for a few months.
Adjusted the valves, put about ~700 miles on it, no problems.
Installed Acerbis tank,
Bike began popping from the exhaust.
about an hour later it began sputtering and losing power.
half an hour later it would barely run.

Installed a new coil, bike ran a little better.
Installed new plug, bike ran even a little better.

After a few minutes of riding, it went back to having problems.

Bike will fire up easy, idles fine, once you start riding around and giving it throttle it bogs down and dies. Plug will be fouled and fuel is in the intake (possibly from the pumper jet).

Carb has been thoroughly cleaned and inspected, no leaks at all.

I am now inspecting for an electrical problem. I checked the kill switch, seems to be no issues there.
I even took off the security switch I installed next to the coil, no difference.
I checked for spots where the wires could be rubbing, or loose connections. Flexing and bending the wiring to the CDI and stator made no difference in how the bike is running.

Bike will idle now with the choke on, but barely idles with the choke off. Problem is now at its worst.

CDI? Regulator? or Stator?

[RuggedExposure]

Here is the stator:


How can I tell if this is operating properly? Anyone see any problems?

[MrPulldown]

Did you new coil include plug wires and spark plug cap? The stock unit has some kind of resitor in it that can get funcky.

http://thisoldtractor.com/gtbender/d...g_resistor_cap

[RuggedExposure]

Originally Posted by MrPulldown

Did you new coil include plug wires and spark plug cap? The stock unit has some kind of resitor in it that can get funcky.

http://thisoldtractor.com/gtbender/d...g_resistor_cap

No, I reused the old line and cap. Where is the resistor?

[Wadester]

Originally Posted by RuggedExposure

No, I reused the old line and cap. Where is the resistor?

In the cap at the plug:

http://www.ngksparkplugs.com/product...tor_covers.asp



Also - I always thought that resistors in spark systems were for noise reduction, but:

http://www.ultralightnews.ca/article...psandplugs.htm

"At a voltage of about 7KV the plug fires (irrespective of resistance). Until that happens NO CURRENT FLOWS. Whether you have resistance or not does not matter. A paltry 5KOhms does not do anything when compared to the nearly infinite resistance of the gap itself (until the plug fires that is). Once the plug fires the resistance comes into play. The coil cannot get rid of its energy in the shortest possible time due to the resistance.
This reduces current flow in the spark and it takes quite a bit longer until the energy in the coil has expelled itself via resistor and spark gap. This results in a longer spark. However the spark is weaker due to energy loss in the resistor."

[RuggedExposure]

Originally Posted by Wadester

In the cap at the plug:

http://www.ngksparkplugs.com/product...tor_covers.asp



Also - I always thought that resistors in spark systems were for noise reduction, but:

http://www.ultralightnews.ca/article...psandplugs.htm

"At a voltage of about 7KV the plug fires (irrespective of resistance). Until that happens NO CURRENT FLOWS. Whether you have resistance or not does not matter. A paltry 5KOhms does not do anything when compared to the nearly infinite resistance of the gap itself (until the plug fires that is). Once the plug fires the resistance comes into play. The coil cannot get rid of its energy in the shortest possible time due to the resistance.
This reduces current flow in the spark and it takes quite a bit longer until the energy in the coil has expelled itself via resistor and spark gap. This results in a longer spark. However the spark is weaker due to energy loss in the resistor."

Can I buy these here in southern NM or do I have to order online?

[MrPulldown]

Most napa autos and autozones are NGK suppliers. If your local auto parts shop does not carry it, I am sure they can get it for you in a hurry.

[Wadester]

After reading that article and thinking - if the resistor is flaking out, you'd be better w/o it. You can try your luck by just replacing the boot - or the whole wire with a known good one.

For a replacement resistor cap - ask at an autoparts place. I found this on O'Reilly's site: http://www.oreillyauto.com/site/c/de...0607&ppt=C0150

[levain]

Great condition, but waaaay overpriced?????

[RuggedExposure]

Originally Posted by levain

Great condition, but waaaay overpriced?????

Way too much. And as its turning out, no matter how new these junkers seem, they have problems.

Or maybe I'm just being pessimistic since I got mine in Sept and it stopped working in December...