Jump to content
Sign in to follow this  

DR-Z400E starting/valve problem?

Recommended Posts

Hi, I bought a 2000 DR-Z400E about 2 months ago. A week or so back I had the battery recharged because it was really low. It ran great at the desert, but it was getting harder to start and eventually I had to choke it with full throttle engaged just to fire it up when the engine was warm. The last day there the battery was about dead so I hooked it up to a jumper / charger that a friend had. After that the battery seemed fine but it wouldn't start. A friend whos a mechanic said to change the spark plug. I did that but still no start. It's acting like it has low compression, the engine starter turns over but nothing happens. The friend then told me it was likely to be the valves out of adjustment. I had a minor suspicion it could be the carb but I doubt it. My question is, has anyone had the same problem? I thought these bikes were supposed to have a solid reliable valve system. While I don't deny it could be the valves I just wanted to see if anyone has had the same issue and fixed it so I can better educate myself before I start stripping the bike apart.

Share this post


Link to post
Share on other sites

Also when it was acting up it wouldn't idle (choked or not) for long before cutting out. If that helps diagnose the problem at all.

Share this post


Link to post
Share on other sites

Mine did something similar when the valves died on mine. Started ok cold but eventually got so hard to start when hot that it'd only bump start.

The valves on these things are generally pretty good AS LONG AS THEY DON'T INGEST DIRT. The valves have a hardened coating on them that wears away when dirt gets into the system. This then causes the valves to wear and go out of spec. You can adjust them but they go right of spec again.

Check your valve clearances. It's easy. If they're ok post again and we'll go from there. Has it had a valve adjustment before? A 2000 model could have some major miles on it.

Share this post


Link to post
Share on other sites
...It ran great at the desert, but it was getting harder to start and eventually I had to choke it with full throttle engaged just to fire it up when the engine was warm. ...

Great place to get sand and dirt in the engine if the air filter isn't oiled properly, is torn, or not properly in place. Pull the filter and look in the airbox to see if you can see dust going down into the carb.

Share this post


Link to post
Share on other sites

Well I bought it from an older guy and just him and his friend owned it before, he estimated it had about 5000 miles on it. I heard to check clearances around every 3000 or close to that. I'm cleaning it up now before I open the valve cover, I thought the filter looked ok but I didn't think of taking it off, thanks for the advice with that I'll post again soon with the situation

Share this post


Link to post
Share on other sites

yep....check valves.... if the valves are good your battery is most likely toast. a weak battery is going to have a tough time spinning the motor over.

Share this post


Link to post
Share on other sites

Well I cleaned the air filter out. It was dirty but not too bad. Checked the valve clearance and it's a little off spec I guess that's it. The battery I have is pretty crap but I have to live with it for now because I have no money. Thanks to everyone who responded, does anyone have any good links to a tutorial on how to adjust the valve clearance?

Share this post


Link to post
Share on other sites
Well I cleaned the air filter out. It was dirty but not too bad. Checked the valve clearance and it's a little off spec I guess that's it. The battery I have is pretty crap but I have to live with it for now because I have no money. Thanks to everyone who responded, does anyone have any good links to a tutorial on how to adjust the valve clearance?

How out of spec are they?

Share this post


Link to post
Share on other sites

Thanks for the links. The clearance they are supposed to have is 0.20mm to 0.30mm for the exhaust and 0.10mm to 0.20mm for intake. Mine barely had 0.2 on the exhaust and the intake was less than 0.1. I don't have a shim kit and the places around here want 90 frickin dollars for them so at that rate I might just take it to the town mechanic / abortionist.

Share this post


Link to post
Share on other sites

It seems like you believe its the valve clearence. I would strongly urge you, please, before you take it to a mechanic, replace the battery. I know a lot of people are going to say that the ignition is seperate. But I had a very similar problem and replacing the battery solved it. period. Your battery is bad. You have to replace it anyway. replace what you know is broken before you start guessing and splending a lot of money. batteries go bad all the time. Valves don't. The guy that sold you the bike knew the battery was bad but didn't want to spend the 60 to 100 dollars to replace it. On second thought, also check that the charging system is working. Your stator, both ignition and charging, could have been fried by hot or low oil. A shorted stator good be giving out whacky signals to ignition. Really if it was me. I would have already hooked it up with good connections to my car battery, bypassing my motorcycle battery. I really think its an electrical problem. Keep us posted. The DRZ repair manual is pretty good at describing have to troubleshoot the ignition circuit. Is the spark super strong?

Edited by toadl

Share this post


Link to post
Share on other sites

You may need another battery, but you DO need to get the valves set properly.

Share this post


Link to post
Share on other sites

Well it could be a combination of out of spec valves and the battery. Because it was acting just like an old lt230 quadrunner we have. Initially I thought I had just run the battery down on it, so we got a new one but still no ignition. Compression on it was low so the mechanic friend looked at it and the valves were out of spec, he adjusted them and now it's running fine again. But regardless of getting the valves adjusted I was planning on getting a new battery when I can. About 5 weeks back it was getting low, I put it on a tender and that helped up until last weekend when it got to the point where it was too weak again. But now even when I had it hooked up to a jumper it wouldn't start. I dunno I'll get the valves done and then post back whether that fixed it or not.

Share this post


Link to post
Share on other sites

The valves should not stop it from starting until the clearance hits zero.

You have checked and your oil does not smell like gas?

It would not hurt to unplug the charging connector below the R/R and see if that affects *how the bike runs*. It is the connector with 3 yellow wires just in front of the airbox door. If the bike starts and runs better with that disconnected you likely have a shorted to the signal coil in the stator assembly.

If you have not been riding that much and have done a lot of cranking for starting the battery may not be bad.

Are you using PROPER "Foam Air Filter Oil"? Using engine oil on the filter will cost you valves/top ends. It should be sticky and leave threads between your fingers if you pinch and open.

Edited by slowriding
clarify.

Share this post


Link to post
Share on other sites

Well I took it to a mechanic and it was the valves, got them adjusted and now it starts up just fine even on the low battery it has. I cleaned the air filter and re-oiled it so that won't be a problem. Thanks everyone for the help, stay classy san diego

Share this post


Link to post
Share on other sites

be prepared to do a valve job as the valves will soon be back 0 clearance. once they start receding they will not stop.

Share this post


Link to post
Share on other sites

Create an account or sign in to comment

You need to be a member in order to leave a comment

Reply with:

Sign in to follow this  

×