DRZ400S WON'T START

Lee Frost

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My 2007 DRZ400s (bought in April but hardly used since then) won't start. It turns over, but won't fire-up. I've almost flattened a full battery twice now trying to start it! It did run fine but had stood in my shed for the last 3 months.

1. Could it be a weak battery? The headlight dims when I hit the start button, though I recently had a 2nd hand Lynx fairing with HiDs fitted so I'm not sure if it's supposed to do that to aid starting as the light pull a lot of power from the battery? The battery stays on an Optimate so it's always well charged.
2. Didn't realise that my bike has a vacuum petcock. Had older DRZs before with a manual petcock. I wondered why there was no 'Off' position on the tap - just 'On', 'Res' and 'Pri'. I could have inadvertently left the tap on the 'Pri' position for the last 3 months stupidly assuming that was the same as 'Off' so fuel has been able to run into the carb. Could fuel have filled the carb, got through the vacuum hose and into the cylinder, causing the starting issue?
3. Could it be the spark plug? Removing the plug on the DRZ is a pain - seat off, tank off etc!

I've got the battery on charge and will try again tomorrow, but wondered if anyone else has had a the same issue.
I'm a totally numpty when it comes to bite mechanics, btw!
 
Put a spare plug in the cap and rest on frame/engine and just make sure theres a spark there before ripping it all downtto get the fitted plug out. I think/remember theres a cross headed drain screw at the carb base. drain it and let it fill again just to check the float hasnt stuck up.
HTHY
 
A combination of stale fuel and discharged battery,probably fouled the plug.
modern fuel is a bit shit.
Bite the bullet and whip the plug out,burn the old fuel off the plug on a gas ring, or fit a new one.
Get some fresh fuel in it and drain the float bowl.
Make sure the battery is good before trying again..
Some folk,start and run their bikes every week or so,but it really is better to only fire them up if they are going to reach operating temp or going for a ride
 
Thanks chaps. I think your diagnosis is probably right Mikeyboy. Shame it’s such a pain getting the plug out of a DRZ!
 
Fuel diluting the oil has been known to happen with other DRs. I think it's worth checking. But I'd expect an external leak too via the overflow. And in complete contrast .. check the needle valve isn't stuck and the carb is empty. Based on my DR350 experience. Is the plug wet? Open the drain screw to check for fuel..
Other comments about stale fuel and spark plug valid too. Oh, and disconnect your headlight.
 
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Check the Oil level is not higher due to fuel polluting it, if thats fine try spraying some easy start or propane into the air box to give it boost.
You might try it with the tap set to prime too just in case the vac rubbers faulty.
 
Riding the strata Florida in winter with drz riders will make an expert of you!!
Same with an x challenge what a ball ache:blast
Edit,,,
Flooded 990 was worse.

Yes we had to run a 990 with the oil filter out on Strata Florida a couple of years ago after it became waterlogged. :D
 
Good fun if it’s not your bike:D

I told the owner it would be all right but to be fair he didn't have a choice, then suggested all the lc8 bikes going to Iceland fit a stainless oil filter :D
 
Hmmm was thinking of one for my wife, I have a nice 550 husaberg I'm not using these days?
 
Lee are you still living at the same place near Alnwick and is the DRZ up here , if so I have no problem popping along at the weekend , I've got a spare coil, cdi and new iridium plug off the CCM404 to see if it will go ,most probably just fuel and a fouled plug .

PM me if it is any use
 
IMG_1293.jpg

Rhayader Golf Course

I think that I'd make the effort and whistle the plug out and pop a new one in; drain the tank and replenish with fresh fuel and give it another go. Check for a spark whilst you have it apart.
 
Lee are you still living at the same place near Alnwick and is the DRZ up here , if so I have no problem popping along at the weekend , I've got a spare coil, cdi and new iridium plug off the CCM404 to see if it will go ,most probably just fuel and a fouled plug .

PM me if it is any use

That's very kind of you Neil, but for my sins I'm now living in Surrey - 350 miles south :blast
 
IMG_1293.jpg

Rhayader Golf Course

I think that I'd make the effort and whistle the plug out and pop a new one in; drain the tank and replenish with fresh fuel and give it another go. Check for a spark whilst you have it apart.


That's the plan Greg. I suspect the plug has been fouled as the bike turns over as normal but doesn't fire.
 
That's the plan Greg. I suspect the plug has been fouled as the bike turns over as normal but doesn't fire.

Yes Lee but the plug has fouled because the fuel is stale, you'll probably get away with just draining the carb :beerjug:
 
Yes Lee but the plug has fouled because the fuel is stale, you'll probably get away with just draining the carb :beerjug:

You were spot on Tim :beerjug:
I drained the tank, then drained the carb, popped some fresh fuel in and it fired up almost immediately :thumb2
 


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