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Discussion Starter #1
Has anyone don any engine mods on the 850 yet. Any head work or cams or different injectors or high comp pistons. If so what were the results?
 

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Speedwerx is the only company offering cams for them that I've found so far. Talking to them , good for 2-3 hp alone. Not worth $900 IMO. But with that, bumping compression, bigger valves, and some other things you can get one to about 115hp on straight C116 racing fuel.
 

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I'm with you about the $900 for a cam. But bumping compression, bigger valves and some head work sounds good. Not the C116 though, but 93 is doable. Has nobody done this?
 

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I'm with you about the $900 for a cam. But bumping compression, bigger valves and some head work sounds good. Not the C116 though, but 93 is doable. Has nobody done this?
It would probably cost you triple that 900 to get pistons/rods and proper head work done.
 

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seen a 850 put down 92rwhp with these mods just to say no my bike ive just seen this done.

12.5:1 kit
ported and polished heads
fired rings
duel state line custom exhaust
bigger fuel pump (more line pressure)
stm full clutches (worth the money my 850 pulls like a can-am 1000 with them)
intake scope on top of box (lot more air)
custom 44mm throttle bodies (2mm bigger then the HO)
pcv with timing


I think I got all of it, you got to think that's big gain from stock 43-45 rwhp more then double the power. I only seen it on a dyno, never actually rode it.
 

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^^^. Vids or it didn't happen
 

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^^^. Vids or it didn't happen
wish I still had videos, not my bike. I don't got 8 grand+ to drop into just a motor, im amazed more people don't build these 850s up, the bottom ends are tanks........just need stronger rods.
 
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