XR650L mods... how does my plug look?

Just completed Daves Mods (160/55), removed smog, uni filter, supertrapp IDS2 exhaust, and ground pipe welds.

First ride exposed a hick-up at 10-25% throttle so I adjusted the air mixture screw and found 1 1/2 turns worked best (started at 2 1/4). Pulled the plug after about 20 miles of typical riding and think it looks pretty good. What do you all think? Also I'm running an NGK DPR8EA9 is that a good plug for my mods? I ride 75% on and 25% off road.

NOTE: the ground electro strap is a bit lighter in person than the image.

pics025.jpg

I think it looks just about perfect:thumbsup:

I think it's about right myself. Runs pretty good now with the mods.

Doesn`t mean much......you need to do a plug chop test to really know how the main jet reads...........anything less is just a mixture of fuel screw,pilot and main.........the main could be rich.....but the low speed ride near home will make the plug look decent due to the fuel screw and pilot being fairly close......

B

......you need to do a plug chop test to really know how the main jet reads

How do I perform a chop test? Thanks.

Basically all you do is get a new plug,,Stick it in then go roaring down the road at highish revs or speed..Then stop immediately and shut her down ,,then burn your fingers pulling the plug out so you can look at its colour..Yours looks good enough to me but I;m no fuss pot...Here's a good site for you on all sorts of stuff..

http://www.dansmc.com/MC_repaircourse.htm

and from that site,,,

To get a true plug color reading you must run the engine,on a level road, at the throttle setting that you want to test, for about a mile, then kill the ignition, pull the clutch in and coast to a stop. Then pull the plug and look at it.

and again from Dans,,,

http://www.dansmc.com/Spark_Plugs/Spark_Plugs_catalog.html

That is one heck of a good site..Bookmarked for sure...

Yup.........what Horri said..........different throttle openings will uses different parts of the carb..wide open throttle,pull the clutch and kill it at the same time will tell you your main jet if you pull the plug on the side of the road,depends on how accurate you want to be.......Horri`s links will help if you want it really close....:thumbsup:

B

that looks good. i checked mine the other day and its a light gray/tan. i checked my buddys also, his bike setup the same other then main jet and his was a light tan. both looked good. mine my be a tad fat, but not enough for me to rejet it. the bike runs outstanding. 55 pilot/160 main. my buddys is 55 pilot/158 main at sealevel. im 2 1/4 out on the screw. not sure what he is.

how many disk are in the muffler? if you feel like your a little lean, take out one or two disk.

I always thought if I didnt have any throttle surge or hick-ups at high speed (3/4-full throttle) then the main jet was good. Although, after these mods I had noticiable gains in the low end but think the top end is lacking a bit from stock. Could that be a main jetting issue?

how many disk are in the muffler? if you feel like your a little lean, take out one or two disk.

I put them all in... I think 12. Thanks for the tip.

i dont think with the mods, your going to do anything with the top end. its all going to be low end power.these motors are lowend motors. they dont like to be rev'd high.

i dont think with the mods, your going to do anything with the top end. its all going to be low end power.these motors are lowend motors. they dont like to be rev'd high.

I wasnt looking to increase top end but believe I lost some doing the mods. Still cruises nice at 65 but takes some time to get higher than 70.

what size sprockets you running?

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