1983-84 ATC 205R Carburetor

[ianj454]

Hello,

I am currently working on my 1984 ATC 250R project bike. I bought this bike off a co-worker who had intentions of rebuilding it. He ordered a pile of new parts and started rebuilding. He then had to move away for work and it sat for 5 years. When I purchased it off him i finished the motor rebuild and got the thing moving and stopping. The bike came with the wrong carb ( a keihin 37mm code 37 AAWL) I managed to get the bike idle properly with this carb but it is starving for fuel at high revs, and idles high when slowing down from moving. I ordered a carb off ebay that said was a stock carb off an 84 ( keihin 30mm code 30 AAVG), and only got around to cleaning it up today. Upon installing I found this carb does not fit the intake and air box boots. It is smaller on both sides. I was wondering would someone know the correct carb for this bike? or am I better off trying to make the 37mm work (which will be difficult since it is such a weird size carb). The only thing different from stock on this bike is it has a brand new dg pipe and silencer combo. Any help will be appreciated!

Thanks

Ian

[manbearpig]

its likely that the stock boots on both ends were stretched out to fit that larger carb. your best bet would be to find a good used (unstretched) intake boot and good used carb to airbox boot and install.

i may have both. PM me.

[ianj454]

I doubt both were stretched. I bought the reeds and intake boot separately from the bike. I am going to measure both the intake side and air box side of both the carbs

[jacobfour]

That should be the correct carb. I got a 32mm carb and could barely get oem 30mm intake boot to stretch to fit the 32mm aftermarket carb so I would think u got some different intake boots, some people can heat them up to make em stretch. which by the way do not get mikuni 32mm carb its been a jetting nightmare. Ive herd if go to autozone or O'Reilly's and look at their cold intake section some of those reducer connectors may fit as far as the air box to carb go. but reeds to carb intake boot ull have to find one off ebay. 84-83 was 30mm 81-82 27mm. so make sure u get 83-84 for it to fit.

[dibbs]

Hey fellas I am new to the thread and it looks like you guys haven't written for a couple of years now. I am having carb problems with my 83 250r. I have taken it out multiple time and have cleaned out the carbs. The floats seem to be working fine. The problem just started a year ago and the carb will just start dumping gas into the muffler, not so much in the actual piston. The carb will stop the gas from leaking until I actually start kicking on it. Once I start kicking on it the gas seem to dump into the muffler where I see puddles under the front and rear of muffler. I was going to just buy a stinkn new carburetor but I am having difficulties finding the right one for the bike. My bike has been bored out to a 310 and I have currently run 350 jets in the carbs and it has done great for about 5 years. Any help would be mucho appreciated!

Thanks - dibbs

[deejaycee_2000]

When last did you inspect your reeds? ... the 83' 250R carb comes with a 50 pilot and a 130 main, on a big bore I would run 55 pilot and a 210 main ... are you running a 350 main? If you are I think that is your problem right there!

[dibbs]

Thanks for the reply. I have not checked the reeds. I will pull them and check. I am not the most knowledgeable on the carburetor but I am not sure what the 50 pilot is. I know where it is but not sure of the function. The main jet was at 290 when I received the bike 12 years ago and it blew a piston. I talked with a local bike shop and I decided that I would rather foul a plug and go big and just started out with a 350 main jet instead of running lean and taking out another piston. It has ran great for the last 10 years with the 350 main jet in it so I didn't think that might be the problem. I am willing to listen to an expert because I am willing to learn. Maybe it is worth taking in to have it looked at? The problem is I don't learn that way if you know what I mean!

[350for350]

50 is the size number on the pilot jet.