yosty

Problem solved. I picked up a dirty '80 MX100 carb off ebay for $25 and cleaned it up. Also picked up a UNI foam filter. Tore down and cleaned the new carb and left it at the stock jetting (the same as the DT100). The bike runs like a top with the foam filter at almost stock settings (1/2 turn difference on the pilot air screw). Also got rid of the stalling when I shake the bike. Thanks to all for the help. My other carb is to beat up I suppose...

I've gone through the carb twice now looking for problems and making sure its clean. I've messed with all combinations of throttle stop and pilot air at two different float levels. With the floats set as they were it only idled with the choke on. Even when I turned the pilot air screw all the way in. To me this sounds like a lean condition, which I think I can fix with a larger pilot jet. Is that sound judgement?

I hear you about the float height. I rechecked all the jets, all seem good. I think that the extra air flow is the culprit. So I'm going to rejet the carb. Stock was 17.5 pilot and 130 main. I just ordered a 20 pilot and 135 and 140 mains. Also, ordered a 44mm POD filter to fit my 43mm flange. Hopefully that will get it set right with the stock float height. That kit is awesome, thanks I didn't know about Keyster. I'm not going to get it though because I think I need non stock jetting. Also, the problem with my pilot air screw is that the threads in the carb body have been stripped by someone messing around with a screwdriver that was too big. So to fix that I need a new carb body as well as a new screw... Either this rejet will work or I'll buy a replacement carb.

Yeah, I think we're on the same page. The bike runs well at mid throttle with the float set higher than stock AND the choke on. This leads me to believe the air filter I made is flowing more air than stock. I'd like it to run with the choke off because whenever I'm riding around the choke rattles itself off and the bike stalls when I come off the throttle. In order of pain in the ass level, I think I need to: a- set the float higher still b- put in a more restrictive air filter c- get bigger pilot and possibly main jets d- get a different carb that has an adjustable clip position and a pilot air screw that is not on the verge of stripping.

I agree about the need for a filter in the desert. As for changing the clip on the needle, that would have been my next step except that the Mikuni VM20SS that is stock on my bike has a fixed needle clip, no way to adjust it. http://books.google.com/books?id=CgqnqoODm...a3mCQ#PPA198,M1 It seems like upping the float passed where it was should help all the jets richen up. But if that doesn't work I either need at least a bigger pilot jet or a different carb...

Im open to the idea but if its not passing enough air, why would I need the choke to run with the carb float set higher than stock (more fuel in the bowl)? I made it out of 1/2" thick, air conditioner foam... doesn't seem restrictive.

Have you checked the emulsion tubes (needle jet orifices) on either set of carbs? http://www.factorypro.com/products/Mikuni_...le_jet_buy.html Would cause rich condition as you come off idle... Also, the FZR idle is 1500rpm, correct? and you say its fine above 2000? Check your charging system, or run it off a car battery and see if you still have the problem. The FZR CDI hates low voltage.

I'll double check the pilot jet when I pull it again to reset the carb.

Thanks, I dont think there's water in it, I cleaned it out two days ago and I live in the desert.

I had already stripped the carb down and cleaned it with carb cleaner and compressed air. Yesterday I took the carb off again, the float was already set higher than spec (smaller measurement, about .75") Seemed strange since that should richen the mixture right? And I was already having to run it with the choke. I decided to try the stock settings: I set the float to .83" and the pilot screw to 2 turns out as per these pages: http://books.google.com/books?id=CgqnqoODm...a3mCQ#PPA198,M1 and http://books.google.com/books?id=CgqnqoODm...a3mCQ#PPA192,M1 Bike is much worse at stock settings, wont rev at all, and needs full choke to stay at idle. With the old settings it would only need a little choke and revved up fine. My current thinking is that the foam filter I made for the bike is flowing more air than the stock paper one. My next step is trying the float a little higher than it was, maybe .70" Also, the head on the pilot air screw is slowly stripping, as the threads in the carb body were eaten up by someone else that used a screwdriver that was too big. Any thoughts? With the float now set at stock spec, yes. Before I changed it, no.

Thanks Dave, yeah I got the float level from that manual too as .83" I'll check that too. Already cleaned the carb... see above. Air filter is my own design, foam cut to fit, with UNI filter oil. I suppose that could be letting to much air through...

So I just found this manual online at google books: http://books.google.com/books?id=CgqnqoODm...a3mCQ#PPA198,M1 So the stock setting for my pilot air screw on a DT100K (1983) is 2 turns out. I'm gonna go try playing with that, I'll let you all know.

Hey all, I'm new to the site and I just got a DT100 for my girlfriend. It starts up great, one or two kicks. But I have to keep the choke just a little bit on to keep it idling. Also, when it's idling if i rock it left to right it stalls. I've already taken the carb apart and cleaned it. I've tried a bunch of different settings with the throttle stop and pilot air screw. I've noticed that maybe my pilot air screw doesn't come out as far as it should, it seems like some of the threads are stripped out, but I can't see why it would need more pilot air anyway if I have to choke it already. I'd like two things: -First, if anyone has any ideas about why it stalls when I shake it I'd love the advice. -Second, what's the stock settings for the pilot air screw? How many turns out? Really appreciate any help. -Yosty