Odd Jets in new L

Hi all. Here's my story. I just purchased a '93 XR650L that was bone-stock, with smog removed. Well, I have added a K&N filter, opened airbox, Supertrapp racing exhaust and jetted the carb. Here's where things get odd. The carb had the stock main installed, but it had a 60 long pilot. Well, the 55 short pilot that I have just installed has an obviously larger hole in it than the 60 long. Both pilot jets have the keihin star on them. Now, why is the 55 short larger inside diameter than the 60 long???? The bike seems to be running way too rich now on the pilot, with the 55 short, with a huge lag in response. It seemed a little lean with the long 60 and now its too rich with a short 55. What gives???:thumbsup:

Hi all. Here's my story. I just purchased a '93 XR650L that was bone-stock, with smog removed. Well, I have added a K&N filter, opened airbox, Supertrapp racing exhaust and jetted the carb. Here's where things get odd. The carb had the stock main installed, but it had a 60 long pilot. Well, the 55 short pilot that I have just installed has an obviously larger hole in it than the 60 long. Both pilot jets have the keihin star on them. Now, why is the 55 short larger inside diameter than the 60 long???? The bike seems to be running way too rich now on the pilot, with the 55 short, with a huge lag in response. It seemed a little lean with the long 60 and now its too rich with a short 55. What gives???:thumbsup:

may not be the pilot causing the lag. where is the needle set, has it been shimmed?

you sure its the stock keihin cv carb? has the slide been drilled?

oh, K&n's ok for street, no good for dirt. go with a uni foam for dirt.

Hi all. Here's my story. I just purchased a '93 XR650L that was bone-stock, with smog removed. Well, I have added a K&N filter, opened airbox, Supertrapp racing exhaust and jetted the carb. Here's where things get odd. The carb had the stock main installed, but it had a 60 long pilot. Well, the 55 short pilot that I have just installed has an obviously larger hole in it than the 60 long. Both pilot jets have the keihin star on them. Now, why is the 55 short larger inside diameter than the 60 long???? The bike seems to be running way too rich now on the pilot, with the 55 short, with a huge lag in response. It seemed a little lean with the long 60 and now its too rich with a short 55. What gives???:thumbsup:

This doesn't really make sense. Can you post a photo of the jets. I'm thinking that one must not be the right type. On these Keihin jets the number is hundredths of millimeters. A 55 jet has a hole .55mm in diameter. The pilot has holes in the side (emulsifying) below the metering hole. Those jets come in a S subtype. The side holes are smaller in the S subtype. The number for those would be 55S.

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