I was starting to price out the big bore kit, but the bikeman kit + bolt on performer kit comes to $3500 anyways.
Talking to CNS, they said the BOV helps with the bottom and bog as well, so hopefully that's the case.
So, in my experience, the big bore at least on the older m8's was a farce, they claim big hp but i call bs and the one we had sure didn't, it made it much more torquey lower end but beyond that... ate a ton of fuel, should of went turbo lol., If you do the math and assume ok at sea level the ctec 800 is ~162 hp. , so a 800 is 162 hp, and a 900 is a 12.5% increase in displacement. so doing the math your in *theory* 182.25 hp at sea level. It too suffers from elevation all the same, but lets pretend you don't loose that extra ~20hp at all due to any elevation, thats only 20 hp more.
Bikeman has a video/dyno run on their 900.. now interestingly they show 200 hp, who knows on the correction factors and all that there. it could very well be true. so you've gained 40 hp there, and deal with elevation, though my math will be wrong, say maybe at 6k feet your 30 hp extra? 30 hp is not too shabby for sure. but same price as a turbo kit? hmm.
Now keep in mind parts replacement, say you pop your top end, you have to pay some hefty $$$ for their special bored/ported cylinders and the pistons, At least a turbo your stock, you will find parts for it and much cheaper, it's not an issue 5 years from now or 10.
And a turbo you're guaranteed power, to a certain point it's said 1# = 10 hp. could be a bit more, and of course due to heat/effeciency stuff, it could be less. you'd only have to run ~ 3# of boost to get to what the big bore does, then maybe you want a bit more, turn it up to 5#, your not limited at all.
A bigger displacement will burn more fuel all the time across the board. Where as the turbo, yes it moves a bit more air but interestingly but when your lower rpm, cruising down the trail your not boosting so your pretty much stock, it usually increases the fuel mileage a tad in those scenarios. then when your playing the boost it sucks it back. My turbo polaris I had usually the same and or sometimes more fuel left in my tank than other pro rmk riders in my group at the end of the day lol.
turbo weight. Think of it this way.... Your removing like a 25# muffler and putting in a ~20# turbo setup back in its place, your stock weight.
And boost/spooling, these ball bearing turbo's have so little lag, like honestly it's more that clutching is bad/wrong,.. From a absolute stand still if the exhaust is cold, yeah maybe a second. If shes warmed up and been riding, Its as fast as you can open that throttle. AND if you're playing already on off the throttle, it is instant. the turbo's already spun out, even if you let off the throttle for a few seconds the turbo still has that momentum in there and it's ready to hit you hard when you open that throttle. A turbo does increase mid range and all that as well, as while its forcing/ driving more air in through the rpm ranges as you rev out.... its making more power. Thats where a lot of the time theres issues hitting the rev limiter, the clutching can't keep up and literally the engine revs out so fast it bounces off the limiter.
A BOV is very important and all kits should have them, It keeps the turbo spinning, Otherwise when you close the throttle its working against the air pressure/flow that literally is going no where so the compressor/turbo slows right down. Now if you have a BOV to dump all that air, the turbo will essentially free wheel and then slow down, so when your on off the throttle, It's ready to hammer you with all that air the engine wants, It's an instant throttle response.
Seriously just watch the turbo alpha/ctec videos, I can't find any lag,
If you go higher boost you have to change gearing, and then thats when you get a small amount of lag because you need the boost to be higher to create more hp to get the track spinning up to speed.
