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How to make 92 rear wheel HP w/XR650R

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This is from the Ebay XR -

"CFI Turbo Continous flow Induction Turbo works by pumping up the power much like a 2 stroke expansion chamber only on the intake side of the 4 stroke, the turbo works by utilizing the velocity of the incomming flow along with high pressure reversion to blast more air-fuel through the tuned tube into the cylinder with each and every stroke, hence more gas more boost it creates, the pulse chamber retains the high pressure reversion and the reversion cone along with the velocity of the intake charge wrk as a one way valve with out restriction or moving parts to contain the high pressure reversion, then the sonic tube blasts the combined pressure back inside the throat of the reverssion cone in the lowpressure area sequenced with the opening of the intake valves..."

If he would add a Splitfire plug I'd bet he could get 93 HP :cry:

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A stock bike puts out about 38~42hp to the rear wheel.

Uncorked about 44~46hp.

After market header, muffler holes in the air filter cover...46~48.

Pumper Carburetor and all the extra goodies 47~51 and about 40~42 foot pounds of torque.

Add the HRC kit and you 48~55.

680 kit with all the more flowing goodies (bigger Exhaust) and your 58~64hp to the groung and somewhere around 50 foot pounds of torque!

Here is something that Qadsan wrote for the Pig Pen

An uncorked XR650R produces close to 42 lb/ft of torque at 5,500 RPM and close to 48 rear wheel HP at 6,500 RPM. The CRF450 comes stock as a full fledged race bike and produces about 29.5 lb/ft of torque at 6,500 RPM and 40 rear wheel HP at 8,000 RPM. The CRF450 has a much broader powerband that's very linear and it will keep pulling where the XR650R falls off in the RPM range, so naturally it will feel faster to some people. Gearing also plays a big role in all of this.

A modified CRF450R that includes a special cam grind that's installed to the correct degree with higher performance valve springs, retainers, guides, porting, 12:5.1 piston, power now valve, Doma exhaust and running Nutec Special 5 fuel produces about 34.7 lb/ft of torque 7,200 RPM and about 53.4 rear wheel HP at 9,200 RPM.

Now if you modify the XR650R with a 680 kit, cam, piston, header & exhaust, you can boost the torque to about 50 lb/ft at 6,000 RPM and raise the rear wheel HP to 64 at 7,500 RPM.

If you take the total torque of the bikes and divide it by the weight of the bikes, you'll get a better idea of the power to weight ratios.

CRF450R @ 29.5 / 225 = 0.1311 lb/ft torque per lb of bike weight.

CRF450R modified @ 34.7 / 225 = 0.1542 ft/lbs torque per lb of bike weight.

XR650R @ 42 / 277 = 0.1515 lb/ft torque per lb of bike weight.

XR650R modified @ 50 / 277 = 0.1805 lb/ft torque per lb of bike weight.

Barnum's Dynamometer doesn't read as high as what some others are getting and his numbers are lower so, that's why there is a range.

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Thanx bwb63!! That's great info, but where is the 92 hp coming from. The velocity intake doesn't get 20-30 hp increase does it? If so, how many $ and where can I get one?

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I don't know where to get the Turbo...muchless about it.

I don't know if that is rear wheel horsepower or at the crank but, with a turbo I wouldn't be suprised if it is at the rear wheel. A turbo will be a big increase in power.

At Edelbrock they made a XR650R flow as much as possible. Biggest cam, ported to it's limit, head opened up as much as possible, 13:1 piston and only read 58+hp on the Dyno....it failed on the dyno! There is about a 25% difference in the bhp (Brake HorsePower read at the crank) and what you will get from a Dyno (read at the rear tire) Honda's 1x Baja bike is to be stock with a HRC cam and piston and claim 67hp that would be 55ph on a Dyno....everyone else is getting between 49hp~52hp so, they are doing real good. 58 hp on the dyno would be 72hp+ at the crank. It's all in the way they play with the numbers.

I did a test between two different dyno's and it was only .4hp difference! That's less then half a hp! The second one was certified calibrated. Different operators, different dyno'd, different places and they did not know I was going to two dynos. So, I am left believing that my bike is putting out 57hp to the rear wheel....+25%?? I will never know I don't have access to an Engine Dyno.

My Updated Dyno Page Click Here:usa:

I don't know if I would want to put the strain of 92hp on a XR650R Motor. All that with little strength and very little

weight it put's out this Horse power! Every one wants to compare HP

(hp per CI)and don't want to hear the BRP dosen't put out killer

numbers, but, for what it is it dose! and dose it for a long time.

I am not comparing it to a V8 as to say it put's out

more HP but, that for how light it is (and they could keep that

weight) It weighs 80 pounds with every thing....transmission, kick start, clutch...everything. I would guess 30~40 pounds for just the engine. Crank, rod, piston, case, valve train...ect. It would be a nice package as a 544hp 240 pound V8 and last!

I didn't write this but, it's said, a lot better then I could say it.

This is worth reading!!!!

A: First, getting a REAL honest to goodness 500HP out of a pump gas street engine isn't an easy thing to do unless you really know what you are doing (which we do) or you are planning on running a supercharger or nitrous. A true 500HP engine will propel a car into the upper 10 second times in the quarter mile (on average), and really, how many street trim 10 second cars do you see running around? Not many I'll bet. There sure are a lot of people that "claim" they have 500HP, but when they hit the track and run a 14 second et, the excuses start flying like a flock of birds why they couldn't pull-off a 10 second, (or even an 11 second) time slip, and the reason they couldn't pull a 10 second time is simple, thay ain't really making 500HP.

Second, always remember this, horsepower is cheap, strength costs money. It's a no brainer to pop a set of 13:1 pistons, a large cam, port-out a set of heads and a few other tricks to get a lot of horsepower out of an engine. Horsepower is a no brainer. It's a simple matter of increasing cylinder pressure, which can be achieved by increasing the static compression, increasing the flow of the heads, or stuffing more fuel and air into the cylinders via a supercharger, or creating a mass of expansion and heat in the cylinders with a shot of nitrous, which is easy and cheap, but will it last? Not if the parts aren't strong enough to handle the stress and heat! The key that needs to be followed is matching the parts so they work together, and building it strong so that it will hold-up under the heat, stress and RPM it's going to be put through. I can easily build a 500 horse small block or even a 750 horse small block for about $2,500 but it ain't going to last but only a few minutes! It must be built with strong parts or it's going to end-up as a large puddle of oil and twisted metal in the middle of the road. Strong, quality parts aren't cheap. There are ads in magazines that offer 350's and even 383 stroker motors with 450 horses for about $3,500, but when you look at what's in them, most of the parts are just crap. They use plain old cast, stock pistons, stock "reconditioned" rods, (which adds nothing to the strength). They use cast iron stock or low priced (and low quality) after market heads, stock cranks, re-used main bolts, head bolts and rod bolts and so on. Remember this, the ONLY thing holding your engine together are the bolts, so they'd better be the best you can buy! There are too many variables to put a single price on an engine, unless it's a generic "crate motor" and with those, you get what you get, with no choices or options. That's why we don't pre-build any "generic" engines.

Third; when comparing engine prices to horsepower, remeber this, you don't pay for horsepower, you pay for quality and strength! Here's a good comparison. A 750HP small block Chevy Sprint Car engine is about a $15,000 engine, and that's including the fuel injection system! The same 750HP small block in Nascar trim suddenly becomes a $40,000 engine, and they don't even have a $5,000 fuel injection system! So why is the Nascar engine so much more expensive for the same amount of power? That's simple. Because the Nascar engine is MUCH stronger and lighter. A Sprint car only has to run a few laps a night to get by, and there's only a little bit of sponsorship money behind the car. A Nascar has to run at 9,000RPM for 400 or 500 miles at a time with millions and millions of contengency and sponsorship money behind the car, so they can't afford to have a failrue because a part couldn't take the stress. The comparison has the same princibles in ANY engine when comparing prices, including street engines. So now you can see, there are lots of options that dictate how strong an engine will be and what it will cost, and it usually doesn't have anything to do with how much power it makes. Always remember, it's the quality and strength you're paying for... not the horsepower.

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It sounds like a load of crap. I see people claim 20 more horses with a slipon muffler on a 400. Unless this is an actual turbo, I don't believe it. Where is the link to this XR?

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