They talked about this same stuff over a month ago. The main things they said that I was intrigued by were:

-unplug the bat while it is running and plug it back in, that resets the cdi and give you more power (but you have to do it every time)

-The pre prod 650 was a 750. Good golly spankin!
-The Production 650 cam was ground to reduce volumetric efficiency above 6500 RPM so the torque disappears above 50mph and you can't go much faster than 65 to 70.
-The production 650 also has a retard in the cdi for above 6500RPM to cut power.
-The engine is durable to 12000RPM, in case anybody wants to CAM and reprogram the cdi.
-Mike penland is makin CAMs (we knew that).
-FST is working on reprogramming the 650 cdi box. I can't fin FST on the WEB.

 

Two replies to all the posts here in this particular subject. I certainly noticed less torque over 50 mph. Now I know why. Thanks NYROC. And I did notice how quiet my 650 is. My buddy was riding in my direction in my 650 going about 30 mph. I could hardly hear the 650 as it approached. I could not hear him until he was about 50-60 yards away. But that distance was about 100 yards as he was going away due to the muffler facing me. But its quiet. Good stealth for hunting season. Heck, that is why I got the darn thing, for hunting adventure.

Daryn

 

Kingmort
We have been working on modifying the black box, and are currently pricing companies to build us an entirely new box to our specs. We managed to disconect all of the limiters designed into the praire to slow it down for production and believe me, there is a lot of horsepower just waiting to come out. We had to destroy the black box to do this so [don't try this at home].
Bearman

 

As I replied to another thread some time back the horsepower was ruduced prior to release due to the driveline, i.e. diffs and shafts, not being strong enough to handle the extra horses. Do we really want to spend more money for more HP just so we can spend mega bucks in repairs? Your choice.

 

Keep us informed Bearman. I am mostly just curious for the time being.And I wouldn't dream of getting into any of the electronics.

Dangerous has a very good point, any more hp could possibly be hazardous to running gear.

What are your opinions on that?

 

nyroc~

FYI: FST Web Site

I've also heard white brothers were making an aftermarket CDI for the Grizz, if they are, I would imagine they would for the Prairie as well.

SilverBear

 

As far as more horsepower hurting the shafts or final drives, very unlikely they are built to withstand much more stress than what they will ever see in the real world. The drive belt is another story, hopefully someone will come up with an after market replacement soon.
Bearman

 

As far as the governor question goes, making the engine produce more high RPM horsepower won't matter to drivetrain. Belt stress from engine is higher at the lower cvt ratio (low speeds). Drivetrain sees highest torque in low range at lower cvt ratios.

Obviously, FST's 750 kit for the 650 will make more low rpm torque, and that will definitely affect the belt and drivetrain. Who knows if somethin will bust. Maybe someone else will make a bigger shaft, hardened cv, high perf belt. I think if we want something, someone will eventually try to make it and sell it to us.

Here is what mickey dunlap at FST told me when I asked him about the CDI:

"We just got our Prairie and we will be doing a magazine article on it around the end of June. I really don't have enough information on whether the ignition timing is going to be a problem. If it's just a rev limiter, we will remove it. If it needs a different timing curve, we may talk to someone else about doing that - possibly MSD. Mainly, we try to build more torque into the machine through high compression pistons, cams and exhaust. If at all possible, I would like to keep the rpm's low and move the machine from point A to point B as quick as possible. This kind of power works best for us in GNCC racing and also works for the mud bog/trail rider."

Did you guys know they already are making a grizzly kit? They pumped it up to 735cc. I would think the 650 is more popular. On second thought, maybe that's cuz the 660 needed a power upgrade more.

 

What size kit would you buy? STD.bore 11:1,.040 over 649cc,.080 over 665cc bore in kits.How about a big bore piston/sleeve kit,85mm 715cc,86mm 732cc or a 89mm 784cc.Will you be willing split the cases to bore them for the bigger sleeve? $375 piston kit? $650 big bore piston/sleeve kit? 2 39mm carb kit $1000/cam and valve spring kit $500/port&flow the heads $600/big valve heads $1040.HP cost money how fast do you whant to go?

 

I think a lot of Prairie owners would be interested more in the cdi mod box rather than big bore kit. It would be awesome to be able to just plug in a different cdi box in 5 minutes rather than having to tear down the motor.