Just bought 2003 drz 125 and having starting problems (carb?)

HI guys this is my first post on thumper talk but I use the site alot for all the info and always found it useful. Anyways I just bought a used 2003 DRZ 125 yesterday for my girlfriend to ride. Im used to working and riding 2 strokes since I ride a Cr 250. Well I couldnt resist the buy because I got the guy to sell it to me for $180. It needs a new muffler, rear wheel bearings and tires soon tho. I got it cheap because it wouldnt start when I went to buy it.The guy said it has been sitting for 6 months. Well today I went and removed the gas tank removed all of the old gas then cleaned the carb. This carb was by far the dirtiest I have ever seen. I had to use a wire brush on a dremel and a whole can of carb spray. I removed all the jets and cleaned them and the ports then blew with compressed air. Once I put the bike back together the bike would fire over with then die instantly. With starting fluid sprayed on the air filter it fired up on choke then would run if I kept on the throttle back and forth. I let it die then tried to start and it only would if the choke was on. Anyways I want to know does this have anything to do with me not having a muffler on it at all ( waiting on one from ebay)? My guess is the previous owner messed with the adjustments thinking it needed it even tho the carb was gunked up. How do I go about fixing the adjustments? Seems like its running lean on gas?

Could be a few things .

#1 Pilot jet / circuit might need cleaned again ? (read up on rejetting the pilot circuit and digging out the air screw)

#2 did you have the needle out of the slide ? Or did the previous owner ?

it's real important that this and the associated parts go back in in the correct order. Check a parts diagram and double check yours.

#3 does it have any compression ? if the air filter was as dirty as the carb it may have worn rings (mine was bad when I got it and the bike looked pretty clean other wise)

#4 check the valve adjustment.

#5 yes no muffler will make it run leaner and these bikes are too lean to begin with. Maybe this should have been #1 ;)

Thanks for the reply

# 1 - I did remove it and it appeared to be clean after blowing out and checking all the small holes.

# 2 - please clearify what you mean by needle out of the slide. If you mean the needle for the float then yes . If you mean the needle for the throttle cable then yest also. I made sure I put it back with the arch facing the back of the bike.

# 3 - I have a cheapo harbor frieght compression guage I can use but will it affect the reading if the muffler still isnt on? Ebay says the muffler will arrive between jan 30- feb 12. Should I wait till then? What should the compression be at? The air filter was just replaced so it was brand new.

# 4 - I know how to check adjustment on small engines ( lawn mowers etc.) How do I go about it? What should it be set at?

# 5 - So should I wait on the muffler then update you?

Sorry for the overload of questions and thanks for the help. New to 4 strokes.

i have worked on a lot of little 4 strokers before old and new and when the carb gets so dirty like you said its better to just buy new jets. i worked on a xl 125 and cleaned the carb and jets about 100 times it seamed like and still had bad performance. took the jets to the bike shop and got new ones and the pilot and main jet had smaller looking holes then the new ones.

some times the dirt just doesn't come off. happened be me and it was very frustrating lol

i also have a 03 drz 125. fun bike when its running good. check your PM after reading this post i might have something that can help you :thumbsup:

also i have gotten burned on a cb 125 before all new jets. cleaned carb, bike is cherry only 1245 miles on it for a 74. but not running just right.

check your float level. thats all it was. put the float level back to stock and it runs like a dream.

just another thing to think about.......

check you pm.

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