Cleaning the carbs the other day, and managed to lose the front main jet **facepalm**. Got an OEM replacement - size 115 - manual lists front as 115 and rear main as 112.5.
Front carb is back together and disassembling rear to clean I notice the main is 106. Pilot is 17.5, and starter is 42.5 (as per manual stock sizes) so I'm assuming the front was the same - forgot to check before reassembling.
Anyone any suggestions as to why PO would have changed rear main to 106? Bike has aftermarket pipes (but I haven't been able to identify them), and stock intake.
i'd say it has been rejetted with a kit.possibly dyno. if the 106 is a dyno jet i would get another 106 jet to replace the one that was lost.a 115 mikuni might be to big.
I think I have identified the pipes - Road Burners. Road burner suggest Dynojet Kit Stage 1 - 110 front, 108 rear (the rear I have is 108, not 106 on re-inspection). The RB jet suggestion because "it could run too lean otherwise". I assume that's hardly gonna be a problem with mikuni 112.5/115.
Someone said on a previous post related to carb issues that one would only need to rejet if changing intake. Clearly PO rejetted based on recommendation from Road Burner - has Dynojet needles also.
Reading the wiki knowledge as well, appears general consensus is staying away from Dyno kits.
Given rest of replacement parts to go back to stock are about $30 - vs $90 for dynojet kit to replace front 110 (can't seem to find anywhere selling single dyno jets), seems worth simply going back to stock?
going with mikuni needles and jets would be best they may have changed the float level in case you have a flooding problem. usually when you change just the pipes you can increase the main jet size one size up or turn the pms screw out a little.
the dyno kit may have recommended a pms change two turns out is stock. you could go 2.5 you turn the screws out to get rid of popping on decell with aftermarket pipes.115 in both cylinders is fine.i checked Niche cycle for needles and there $6.00 each but you got to know what ones to get ha ha.
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