It's a 05 carbed and the owner added 2 -2 inch home made snorkels that came out really nice.This is the highest HP 100% stock internal 750cc machine I have dyno'd yet.
Normally a snorkeled machine is down on power and this one even ran best on Dynojets as where other's don't?? I don't know what's up with this one. but it was working!!
Clutch is still 100% stock I didn't have time to dyno and cut the clutch and we only interested in tuning the carbs. I'd suspect a HP or 2 gain with the clutch cut. but this was plenty impressive the way it was.
Stock 750 VS Pro Pipe 750 look at the 20 mph gains. that's 34rwhp to 51 rwhp. 17 RWHP gain
Lower run was 180 Keihin and Stock needle 40 pilot. 48.51 Bad midrange miss. way too lean but 1/4 throttle and WOT were fine.
the stock needle was too lean midrange. I installed a dynojet needle 4th clip and it was perfect. This suprised me the most. it had to be due to the larger snorkels that this guy made. I can never get DJ needles to work.
I went to 185-185 and DJ needle 4th clip 40 pilot. it was perfect all the way thru, it ran smoother and sounded better than a Fuel injected model (buy I hate Brute carbs) but this came out nice!
That's freakin amazing
These are just some back to back runs when I was done tuning. it's consistent and running like a top
I removed the HMF Penland Full system exhaust system because it fell apart. When it was on there it was just TOO LOUD and I knew it was Hampering performance.
The top line (GREEN) is the Muzzy exhaust full system
Lowerline (BLUE) is the HMF penland Full system
Peak power and low end hit is up. I suspected this just from the Butt dyno. Midrange at 50 MPH was definatly noticeable on the trail.
Dyno confirmed the gains +5.1 rwhp gain @ 50 mph
Peak power is up just +2.48 rwhp but look at how much faster the Muzzy makes the power.
compare the gains at 20 mph. It hits even harder out of the hole. Hard for the seat of the pants to tell as it just spins with it being so cold out and low traction.
For the gains I have seen, all I did was switch the exhaust, and change the pilot jet to a 45. same 3/32 main jets, shimmed stock needle, clutching was not changed. just the exhaust pipe. It was definatly worth it.
Jacks 650 Prairie has 11.5:1 off the shelf Wiseco's 82mm in bore and the 750 66mm crankshaft. this makes his prairie a 697cc machine. same as a stock 700 prairie with the 11.5 wiseco's installed.
He also has Flynt Valve job and light Flynt head porting job.
When he came here he had the web150i cams installed in the machine, stock intakes, stock carbs, piston and crank all setup. here are his base line #'s.
consistant performer all 3 runs.
I then tore the motor down to install the AMR camshafts. I had to remove the heads and full top end down to the pistons, Install the HD AMR Double springs, Modify the Rocker shafts to the free floating Brute750 shafts, and I also Drilled and tapped the rear head for the YFZ box modification (Since the head was off just incase of Oil blowby).
We then installed the AMR drop in camshaft ALONG with the UPP 32mm Crossovers. here's the results we got.
there are 3 runs with the AMR camshafts installed. The AMR cam, and the UPP intakes we had to jet down from a 185-185 to a 170-170. it leaned out the mixture.
there is an overlay of the WEB150i cam VS the AMR drop in cam with UPP's
power was about 1 better at peak and then dipped off fo about 5 mph then came back on pulling more HP the faster it went. at 70 mph it's about 6.5 hp better than the 150i cam
It's hard to say what did what intakes or camshaft since they were both installed at the same time. but regardless there was a small but noticeable gain from the modifications. top end gains were more noticeable past 30 MPH riding the atv.
Stock cam VS Web 150i
the 3 base runs before we swapped out the stock cams for the WEB 150i cams. he was jetted 178-178 jetting was a touch rich for my altitude but for sealevel he'd lean out a hair. He was about .5 a point away from being perfect. or 1 jet size lower
these 3 runs show the web150i cams installed in the 750i Bruteforce and the gains were right on par with what I've seen before from these installs in Vforce. 2-3 hp gain at the wheels. very consistant setup as well.
Also note the RPM gained on shiftout with the web150i cams. without touching the clutch we went from shifting out at about 6800 rpm with the stock cam to 7100 rpm with the 150i. more power the clutch automatically adjusted the RPM of shiftout and we never even touched the clutch.
We also had to jet down to a 160-160 setup to get the a/f back in line. installing these cams we had to JET LOWER.
all jetting and testing was done with the NEW EHS Racing lid with the ALUMINUM cover over the outerwears.
there is an overlay of the 2 power charts 150i is the line at the top. stock cam is the lower hp line. More power bottom to top
pretty decent gains from a drop in cam. No springs or anything required.
Courtesy of Vforcejohn: Stock internal 700 with nitrous
This run compares all motor to on the juice. very nice gains especially when we justused the smallest NOS nozzle with a little help from the drillbit. it was the 3 hole nozzle with 1 of the 3 holes drilled out with a .78mm drillbit (VERRRY small)
I coiuld have got alot more but in order not to compromize the stock pistons we let it be.
these are 3 consecutive runs to show how consistant the NOS hit is with nmaking power to the wheels.
the GREEN LINE shows what happens when you push the button at mid MPH speeds. I pushed, let off for 1 second, and pushed the button again. power shoots up pretty fast. this shows power is on tap whenever you may need it.
66.6 the # of the Devil!! this Dyno chart shows what CAN HAPPEN to someone tuning NOS WITHOUT an a/f meter. What was happening is the Stock Fuel pump was being overpowered by the NOS chargepressurizing the fuel bowls. what we did to correct this was remove the regulator from the STOCK fuel pump and then that just wasn't enough. (I sent TOM for a low PSI fuel pump but it wasn't needed). I then realized how we could get more fuel into the carbs and have them no empty out so fast. I raised the floats as high as they could go.
Without the a/f meter you would assume that the NOS is functioning correctly because even going DESTRUCTIVELY lean the power stayed up there. normal NOS tuning would have led to melted pistons for sure. it was running the carbs ut of fuel
all these NOS runs were done with 1 step colder CR8E Spark Plug for safety.
very cool, the brute with muzzy and snorks is very impressive! not a common thing though correct? every motor is different i guess is what im saying...
i wish i knew what i am going to be pushing.
MODS in sig if you feel like guessing!?!?!
I don't see why it wouldn't make atleast as much if not better. The 650i has a better flowing head and also bigger carbs from the factory. Ill see what I can dig up for ya though.
But remember that when they say 730 or 800 or 840 when talking pistons they use the 750 stroke as the default so a 730 on 650 stroke is a 698 but it will rev a little higher than a 730 because of the stroke
AMR 800 12.5 piston (gas ported, teflon coated, with CP rings)
bored and Nicasiled Brute cylinders
XX cams (new style)
Dynojet PC3 and Ignition module
Larger 24.5 lb injectors
stage 3 spidermod clutch
epi maroon spring
stock heads airbox and throttle bodies
stock air filter
this chart compares his previous setup stock motor with muzzy std and EHS Dobek FI controller and stage 3 clutch with maroon spring.
Here's the comparison of no moose module VS installing a moose module from a CDI/carbed prairie/brute. I cut and spliced it into the EFI computer to override the timing settings all the time. **** it worked for the low end that was missing.
it's a **** good running machine for just a bolt in engine kit.
there was a ton of Map sensor tricks and Idle control tricks that I had done/tried to make it work better. leaving everything that controlled the FI stock (map sensor, temp sensor, IAC control unit) I had it to a best of about 59 rwhp. what would happen is the map sensor voltage would change drastically with every revolution of the motor. not at idle, but just off idle. it would read max lean, max rich about 25x per second causing the computer to blunder and just flood it with fuel causing the lag. but I figured it out.
He had better not crash this thing. it''s far faster than that built 700 Vforce that he has. That's how he blew it up the last time and started this whole build.
Finally after many pitfalls in the build process, it's done. he'll pick it up tonite. I think it will have been worth the wait, It came out better than I had expected. I told him he'd be lucky if I got it to 65.
V force AMR 730 (same motor as brute and prairies)
Little did we know that it was to be the highest hp 730 I've ever dyno'd.
Glenn said he expected 68rwhp out of it. he was exact in his #'s.
Amr 730cc motor
Glenns AMR +1.5 valve heads with full porting
UPP Crossover intakes
Muzzy Pro (coated black to look stock)
Twin air filter.
Stage 3 clutch
EPI maroon spring (too soft)
We tuned for a/f first setting up the pilots and mains. he had 42's in it and it was blowing 19.0 a/f it had a bad bog out of the hole and backfired like a machine gun on decel. we went to 48's and that cured most of the low end and 100% cured the decel poping.
Being he had the new Muzzy Pro on there they come with te 02 bungs pre welded sp that made tuning a breeze. we used mikes supplied factory PRO jets and he came in 215 main jet in the rear and 220 in the front.
I'll post the charts this afternoon soon as I can get them loaded up from the dyno cpu. I have 2 ton of work to get done here today.
Thanks again Mike. I'll get these up for you today. YOu have yourself an AMAZING running (just stock & piped) machine
Here's the best run of the day 68.99 rwhp @ 7990 rpm. we couldn't squeeze 69 out of it. but this is pretty close.
Also note with the high RPM nature of this motor. with 100% stock clutching and an epi maroon it was hitting the limiter @ 8680 at 65-66 mph. The tiny dyno tires are partly to blame for this as well. we ran it to the limiter plenty of times
This is the Average power of most of the runs. power was a very consistant in the average of 68.5 rwhp the Green line shows after the stage 3 clutch. I could have revved it higher and gone faster, but there was no need to do that to a fresh motor.
Whoever says you can't tune a clutch on the dyno to the motor. PAY ATTENTION. Here's how you read the chart to tell you what's up. This chart above shows a stage 3 clutch run with the motor tuned in. You can see it peaks power out at 68.49 rwhp @ 7950 rpm.and this occours at 21.3 mph
Next we will see at 28 mph the motor is revving 7570 rpm. it has lost both power and rpm. This is because of the EPI spring being too soft for this ported big valve motor. it needs a stiffer spring to keep the RPM's held up so they don't drop off. This is obvious by looking at the dip in the chart. Also look how power climbs back up the faster you go. Simply because it's gaining RPM's back as it goes faster. Also note how the power holds to 80 mph it doesn't loose ANY power from 25-80 mph. it's always above 65 to the wheels.
This last chart just shows that at 80 mph it's revving 9290 rpm and still holding over 65 rwhp. It's a very efficent and powerful motor that holds power from start to finish.
With a stiffer spring to keep RPM's up in the power range better, I would feel it could hit 70 rwhp. 68.99 is very close. it has to gain just 1.5 more but as far as 730cc's is concerned. this is the most powerful I've seen to date.
Bottom Line (BLUE) was how he brought it with these parts installed.
- Dynojet jet kit installed, 135-140 dj's, DJ needle stock carbs.
- UPP crossover intakes
- Penland HMF full system
- Closed airbox
- Napa hose mod
- Twinair power flow.
-stock clutches, EPI red primary, EPI black 2ndary
the a/f was really good for the Dynojet kit. 12:1 a/f 42 hp was Impressive!!
Middle line (RED) was tuned in with the stock clutches same setup as above,
- We Removed Dynojet jet kit
- Stock needles put back in.
- 145-148 Keihin mains
power went to 44
Top line (GREEN) All carb settings stayed the same. we added:
-VFJ Stage 3 Spidermod Clutch
-VFJ Drag lightened secondary
46.78 wow! Clutches gave him More low end HP, More midrange HP, More top end HP and Higher top end speeds. All on a smoother operating lighter clutch setup .
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