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xl600lm

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i have a 85 xl600lm.it has always seemed under powered,stock air filter,55 piliot,115 prim,115 sec slightly opened up stock silencer.i live in belfast n.ireland sea level just above freezing.to free some power i removed snorkel and added a uni filter and replaced piliot to 60,prim 120 ans sec 118 which made no difference.so i removed complete air filter cover no change and when adjusting the air screw it does nada.any thoughts would be great.ps checked air cut off valve etc and cleaned carbs still no change.confused tractor.

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Your jetting sizes sound pretty close to what I was running in my stock XL. It it makes no difference with the air screw at idle you may be too rich there. I found that mine liked leaner rather than richer for ease of starting and idle quality as far as the pilot jet was concerned. If it is still gutless on the top end I would look into other things like cam timing and valve adjustment, or worse. You could experiment with slightly larger main jets at those temps, I have run as high as 128's in the early spring here, but that is with a bigger bore than stock.

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Your jetting sizes sound pretty close to what I was running in my stock XL. It it makes no difference with the air screw at idle you may be too rich there. I found that mine liked leaner rather than richer for ease of starting and idle quality as far as the pilot jet was concerned. If it is still gutless on the top end I would look into other things like cam timing and valve adjustment, or worse. You could experiment with slightly larger main jets at those temps, I have run as high as 128's in the early spring here, but that is with a bigger bore than stock.

hi dave,topend power is pretty good it just seems a little flat getting there.today i put a clear plastic tube on the float bowl drain off to check the level and the fuel went straight to the top of the bowl.i done this several times and ended up with the same resault.what do you think.. could it be dirt or do you reckon i should remove the carbs and set the float level.would the float level being so high cause the problems i am having ie hard to start from cold and bad throttle response.cheers trac.

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Hey trac: Sounds like you may be close on your mains if the top end is good. Pilot jets are mainly for the idle circuit and have little to do with mixture control above 1/8 throttle. Needle position and needle jets come into play there. For hard cold starting I might suspect the choke passage may be plugged. The choke is a bypass bleed system that uses its own jetting and passage independent of the other jets. If it starts and idles good warm you are probably close on your pilots too. Float settings usually don't cause much trouble unless high enough to flood, which it would just leaning on the sidestand. Since I detest carb removal on these bikes I have evolved techniques that allow me to remove the float bowls and even change needle settings with the carbs still in place. I have played around extensively with the dual carbs to try to make them work better, allowing the secondary carb to open right after the primary helped throttle response a lot on my bike. I put two small washers under the primary needle clip to lift it a little more, also gaining some midrange there.

I had a problem for quite a while that I thought was one main jet plugging intermittently because it would just go gutless all of a sudden and felt like one carb quit working. If I let it idle a minute it would recover usually. I suspected dirt near the main jet, and cleaned it out numerous times. One day, my stator just died suddenly. I replaced the stator and did nothing more, and have not had the suspected carb dropout issues since. Starting is easier too,so don't overlook that possibility.

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Hey trac: Sounds like you may be close on your mains if the top end is good. Pilot jets are mainly for the idle circuit and have little to do with mixture control above 1/8 throttle. Needle position and needle jets come into play there. For hard cold starting I might suspect the choke passage may be plugged. The choke is a bypass bleed system that uses its own jetting and passage independent of the other jets. If it starts and idles good warm you are probably close on your pilots too. Float settings usually don't cause much trouble unless high enough to flood, which it would just leaning on the sidestand. Since I detest carb removal on these bikes I have evolved techniques that allow me to remove the float bowls and even change needle settings with the carbs still in place. I have played around extensively with the dual carbs to try to make them work better, allowing the secondary carb to open right after the primary helped throttle response a lot on my bike. I put two small washers under the primary needle clip to lift it a little more, also gaining some midrange there.

I had a problem for quite a while that I thought was one main jet plugging intermittently because it would just go gutless all of a sudden and felt like one carb quit working. If I let it idle a minute it would recover usually. I suspected dirt near the main jet, and cleaned it out numerous times. One day, my stator just died suddenly. I replaced the stator and did nothing more, and have not had the suspected carb dropout issues since. Starting is easier too,so don't overlook that possibility.

hi dave,its great getting these detailed replies.ill stick a spare set of carbs on and use a temp gas supply.if i have the same problems ill go for a stator.ill let you know the resaults,many thanks tractor.

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hi dave,its great getting these detailed replies.ill stick a spare set of carbs on and use a temp gas supply.if i have the same problems ill go for a stator.ill let you know the resaults,many thanks tractor.

forgot to say from i got the bike the choke has had no effect while starting.its dual start and i normally kick it over. when i do so it just catches idle at very low revs and if you touch the throttle it dies so i have to let it tick over for a minute before giving it any gas.ill try what you said when i get time as i am super busy with work.my xr 600 actually sarts better since enrichening the piliot(single carb model) that does not seem to be the case with the xl.the xl 600 lm has adjustable needles so ill drop down a notch to see if mid throttle improves.if you think of anything else please let me know.thanks again t.

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Your jetting sizes sound pretty close to what I was running in my stock XL. It it makes no difference with the air screw at idle you may be too rich there. I found that mine liked leaner rather than richer for ease of starting and idle quality as far as the pilot jet was concerned. If it is still gutless on the top end I would look into other things like cam timing and valve adjustment, or worse. You could experiment with slightly larger main jets at those temps, I have run as high as 128's in the early spring here, but that is with a bigger bore than stock.

hi dave,i was out looking at the bike and the top access hole on the stator side has an oil stain(more than a weep) coming from it.i did not think oil would be up around this area.after you mentioning the stator i am getting confused.if you have any thoughts please let me know..a worried tractor.

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