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oem jet sizes

5K views 4 replies 3 participants last post by  nick57 
#1 ·
can anyone tell me the oem jet sizes for the 650 engine, because i keep getting conflicting info in my searches. i'v seen 95 front and 100 on the rear carb. everyone say's rejetting isn't required if you only remove the final baffle, but my plug's and performance say different. the bike pulls very well up to 3/4 throttle but at wot it go's flat unless you back off slightly. the top end is still good at little over 90mph. i don't know if just shimming the needles will do it, or should i go up to a 110 jet which is supposed to be the next size up from oem and maybe shim with just one #4 washer. because it pulls good up to 3/4 throttle i'm assuming the pms screws don't need to be touched.
 
#2 ·
i'd go with upping the main jet one size. i don't know about increasing the shim.if you up the shim i'd check the plugs after 500 miles see if there any darker. most of the time your runnuing at 1/4 throttle so does the shim come into play . if your on the throttle maybe the extra fuel would be a boost or just end up as unburned .
 
#3 ·
the thing is i don't know what the next size up is, i think 110. i'm trying to do it in one shot not having to pull things apart to see what's there then reassemble while i order the jets, then pull it apart again to install the jets, if someone knows for sure that 110 is the next size up i'll get them and install them in one shot. i just don't want to have to attack those brass jis bowl screws twice. i rarely need to go full throttle but if i need it in an emergency to avoid something it has to work right and not make the power go flat.
 
#4 ·
Get 8 - 3mm stainless socket cap screws and never worry about those funky bowl screws again.
 
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