drz400s carb issues

I took apart a good working DRZ400s carb to clean and haven't gotten things right since.

 

Ive taken the jets out to clean twice since then (did not take apart choke assembly) and these are my symptoms:

 

-Only starts with choke fully on.

-Idle surges up and down. Seems as though if I take the bike off the kickstand and set it up right, the idle goes higher

-Bike easily dies if choke switched off, or if given throttle ( sometimes it can handle gas, maybe when really hot?).

-Sometimes wont start at all (even w choke) until I drain the carb of gas and start over

-Some smoke coming from exhaust header where that heat shield is (may be due to the very high choke idle?)

 

-Fuel screw set 3.5 turns out (how it was before I took apart)

-I have my TPS sensor unplugged.

 

any thoughts or suggestions appreciated

Edited by ean

You must clean the various circuits as well as the jets, sounds a little like a plugged Pilot Jet circuit to me. Not sure why draining the float bowl would help? Is the gas clean and is there any foreign matter in the bowl?

Thanks for the response. The gas is a mix of what was in the tank a week ago, and what was in an old gas container that I drained it into, so I'll get a fresh gallon in there.

 

I'm more curious as to what might be causing the surging of the idle....How do I clean the circuits of the carb?

Yes make sure you have fresh gas. Also make sure that the float height is correct, I believe the float height for the BSR36 is 13mm.

Did the little spring/wire that hooks the float needle to the float get put around or on top of the float tange? Does the float move freely? Is the float correct side up? Are the small jets in the correct locations?

Thanks for the response. The gas is a mix of what was in the tank a week ago, and what was in an old gas container that I drained it into, so I'll get a fresh gallon in there.

 

I'm more curious as to what might be causing the surging of the idle....How do I clean the circuits of the carb?

Fresh gas first. That might be the entire problem.

Carb circuits are the passageways drilled through the carb body. To clean the circuits you spray Brake Cleaner through whereever and every where you can get it through. Carb cleaner is very aggressive and can damage rubber quickly thus the brake cleaner suggestion.

Yes make sure you have fresh gas. Also make sure that the float height is correct, I believe the float height for the BSR36 is 13mm.

This is with the carb on its side so the float just holds the needle against the seat but does not compress the spring loaded plunger inside the needle.

I had the same issue it's the ethanol gas clogging the pilot. My solution is to clean the pilot, put a gallon of 110 octane race fuel and run it through. Keep it stored with the 110, when I go riding I fill up with 93. After I ride I drain the tank, put in the Tacoma and put another gallon of 110 in and run it through.

Thanks for the response. The gas is a mix of what was in the tank a week ago, and what was in an old gas container that I drained it into, so I'll get a fresh gallon in there.

 

I'm more curious as to what might be causing the surging of the idle....How do I clean the circuits of the carb?

Take the jets out and use carb cleaner & compressed air if available.  The pilot jet hole is pretty small, so I use a bread tie wire to clear hole with.

Take the jets out and use carb cleaner & compressed air if available. The pilot jet hole is pretty small, so I use a bread tie wire to clear hole with.

Here's the pilot jet in 1st pic.  Like said above, make sure do not or did not mix up the main jet with starter jet.  The main jet will have a bigger number on it like 142.5 vs 62.5.  Here's the main jet in 2nd pic.

1412566721774.jpg

1412567377942.jpg

Edited by Throttle5

Thanks for all your replies. I put in fresh gas and the bike is running great.


Here's the pilot jet in 1st pic.  Like said above, make sure do not or did not mix up the main jet with starter jet.  The main jet will have a bigger number on it like 142.5 vs 62.5.  Here's the main jet in 2nd pic.

Thanks for uploading that pic. What is the purpose of that plastic tab around the jet? Ive never seen that before and my DRZ carb didn't have one when I opened it.

Thanks for all your replies. I put in fresh gas and the bike is running great.

Thanks for uploading that pic. What is the purpose of that plastic tab around the jet? Ive never seen that before and my DRZ carb didn't have one when I opened it.

It's a baffle, to help keep gas from sloshing around.

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