DRZ400SM - Fuel Mixture screw location | GTAMotorcycle.com

DRZ400SM - Fuel Mixture screw location

I

il3dsm

Well-known member
Hey guys,

I got a new (to me) DRZ400sm a while back.
I've noticed mileage isn't too good and exhaust smells like gas, so I'm thinking it's running a bit rich.

I would like to confirm the location of the fuel mixture screw. The bike has been rejetted by previous owner so in theory the cover (?) should be screwed out.
I have checked a video and seen a few pictures so I'm 90% sure this is the one, but just to be sure...

http://i.imgur.com/9PLl3BN.jpg

Is this the one?
 
That's it. Luckily po put in extended fuel screw. Saves you some work. This is for idle mixture. Other jetting work may be needed. Has the airbox been modded?
 
show a picture of the rest of the bike to see if its my old one! cuz when i rejetted mine i put int the extended needle + mrd exhaust + wrapped the pipe + undertail plate/light.
 
corpse said:
show a picture of the rest of the bike to see if its my old one! cuz when i rejetted mine i put int the extended needle + mrd exhaust + wrapped the pipe + undertail plate/light.
Click to expand...


Stock exhaust on mine!

I adjusted the screw, it was out around 3-3.5 turns and I screwed it in so now it's ~2.25 turns out. Still smell gas on stop lights but going to see how it affects the mileage.
Seems to run fine.
 
adjust screw to 1 3/4 turns for stock exhaust and air cleaner, so take it back another 1/2 turn. he must have changed the exhaust back after he sold you the bike, never turn the screw out further 3 turns or 3 1/2 max!!! if you cant make the bike choke while completely closing the mixture screw, you need to step down a jet(smaller). if your used to injected bike and this is your first carbed, this is not unusual to smell some fuel sometimes.

im adding to this post by assuming you know to monitor engine temps and signs of engine overheating when playing around with the mixture screw?? if you are not sure or understand id advise you to get some professional help who can physicaly see whats happening, you can damage your engine severely if you run overly lean. im contemplating deleting my post completely for this reason. play at your own risk!!!!
 
Last edited:
Skully said:
adjust screw to 1 3/4 turns for stock exhaust and air cleaner, so take it back another 1/2 turn. he must have changed the exhaust back after he sold you the bike, never turn the screw out further 3 turns or 3 1/2 max!!! if you cant make the bike choke while completely closing the mixture screw, you need to step down a jet(smaller). if your used to injected bike and this is your first carbed, this is not unusual to smell some fuel sometimes.

im adding to this post by assuming you know to monitor engine temps and signs of engine overheating when playing around with the mixture screw?? if you are not sure or understand id advise you to get some professional help who can physicaly see whats happening, you can damage your engine severely if you run overly lean. im contemplating deleting my post completely for this reason. play at your own risk!!!!
Click to expand...


Hmm I'll play around with it.

My last bike was FI so you may have a point.

It's been fairly cold lately and I've never seen the bike spin its cooling fan. I've changed the coolant not too long ago and took a temperature measurement of the radiator - radiator is at around 50C after riding. Not too hot. Never seen the light either, but I'll assume the circuit will work as expected?
I do try to pay attention to it, but assuming the temperature light doesn't work for some reason it's hard to tell, especially if the bike performs fine. I'm thinking of installing a temperature indicator sensor for the third party speedometer I got for some peace of mind.

I'll see if I can choke it with the screw all the way in.
 
You must log in or register to reply here.

Back
Top Bottom