If you still don't feel that the bike is running it's best at mid range rpm(normal highway speeds) then I would change the two brass washers for two steel washers , that would raise the needle two "tads".( slightly )higher.

eskimo619 wrote on 08/15/18 at 03:15:22:



Do the washers first, and test ride, before doing the main. The jets are cumulative - they affect each other - pilot, needle, main. I found that adjustments to the needle made much more difference than changing the main jet.

eskimo619 wrote on 08/15/18 at 07:29:43:


Keep in mind that the main jet primarily affects the 3/4-full throttle range.

may also just need to let it warm up more before riding.  It just has that little

I start up, drop in gear, go.
If you're not able to ride it on a nice day right after it's fired up, sumpin ain't right.

Carb talk is always fun haha.  Id buy the jetkit from Lancer but I dont have any plans to add a pipe or filter.  Just want it to run better and not so lean like they come from the factory.  Im swapping in 2 steel washers this evening and will see how it rides.  I got such a good deal on it ill most likely sell it for a quick profit but if it doesnt sell then I may consider a pipe down the road lol.  I have a 1992 Honda shadow 1100 I ride when I want a little more power and sound.  But the s40 is so light and nimble its a completely different ride.

Edit:  Installed 2 steel washers in place of the brass washers.  Bike started fine no choke.  Let it idle for about a minute.  Initial take off had some hesitation in the lower throttle positions.  Once fully warmed up it  smoothed out and pulled hard all the way up to 80mph, as indicated on the speedometer.  Think I can live with how it is.  Definetly much better than it was when I bought it.  Now to see if it sells or if Im keeping it.

So I havnt really been able to ride the bike much due to it not being registered but I did ride it a few miles today in the backroads near where I live and the bike is running well.  Pretty smooth through throughout the rev range and rides good at wot cruising 80mph as indicated by the speedometer.  Dont think ill mess with it anymore.  Now to see if it sells or if ill be keeping it for a while longer.

So I still own the bike.  It was sold but heres the story.  I tell the guy im still waiting for the title to arrive in the mail.  He says thats fine and he agreed to pay $1100 up front and remaining $300 when title comes in.  He pays me $1100, we fill out a bill of sale.  He rides the bike home probably a 40 minute ride or so.  Next morning he texts me saying bike has a bad valve.  Im like no way and ask what happened.  He says nothing happened and it rode to his house perfectly.  Im like okay so no way it has a bad valve.  He tells me his father who is a bike mechanic listened to it and heard a backfire and said it has a bad valve.  I had already told him the quirks with these bikes and their lean condition and people that try to tune out the "sneezing" from the exhaust.  I tell him again and he says okay.  Few hours later asks to return it.  Im like fine didnt even want to make it a big deal, he says he will give me $100 for my troubles and will return bike back that next evening, so basically 24 hours from when he bought it.

 I ask if hes riding it or putting it in a truck and he says ride it.  Im thinking well it apparantly has a bad valve so why would he ride it?  I knew it was fine so let him do what he wanted.  He makes it to my house and bike sounds as good as it did when it left.  I ask how it rode he says great.  I tell him bike has zero issues.  He then tells me he still wants to buy it back when the title comes in.  Makes no sense lol.  He also proceeds to tell me he took his girlfriend for a ride on it for about 2 hours that day.  Im thinking well thats messed up considering that morning it had a bad valve lol.  All in all he rode the bike about 180 miles before returning it to me.  He also used my helmet to be able to ride the bike home and still hasnt returned it.  So yeah I still own the bike and its still for sale.  I occassionally bomb down my backroads with it but it just sits in the garage on a trickle charger till someone buys it.  Gotta love when this happens.

So I have a question now that the temp is cooling down.  I never need to choke to start the bike however if i use it, it will actually make the bike stall out instead of idling high.  I end up just turning the idle knob up a bit until the bike warms.  Only thing I did to the carb was the washer mod and bike runs great.  But with the cooler temps im noticing the difference in startups.  I know its common for colder temps to affect bikes but want to make sure I have everything adjusted properly so cold starts arent an issue.