Actually nothing to drastic but substantial just the same. All I have done to increase performance on the 650 is as follows.

1) Modify the muffler as done by Nyroc.
2) Modify the air box as to Mike Penlands specks.
3) Change the jets in the carbs.

The only reason I have done these mods as I happened to race my friends who purchased the new Polaris 700 and as some people who have said that the 650 blew away the 700 maybe on a stock Kawi but not one with 28in. Outlaws. Not only did I not beat them like others have done but only managed to inch my way ahead on the start, As we continued at the half mile mark we were dead even and then they started to pull away from me ever so slight but pull ahead they did. There was 3, 700's and the verdict was the same for all three. We even changed riders and still it was the same no change. The only difference between my 650 stock and the 700 stock was I have 28in. Outlaws and if you don't now these tires are heavy about 30lbs. per tire to be exact. This weight makes the two bikes pretty much equal. Now I posted a thread some time ago telling of this same insident and there was two fellows that had the odassity to say that the bikes were not equal as my bike was too heavy and not a stock Item. In stock form I would have smoked the 700's and you can only race stock machines to be equal. Weight means everything when racing is involved and I mean everthing if you think not then you should talk to some pro's and see what they say.

Anyway it was time to regain some advantage. Talking to Bearman and Mike Penland was very informative and they would have talked my ear off had I the time. Not totally sold on the power lacking issue I went to some drag races here this last weekend and there was these little dragsters that kids from the age of 8-16 race. I later found out they use 5hp Brigs & Straton motors, or Honda and they are getting some whopping 50hp out of these motors naturally asperated without nitrous or alcohol. Truly amazing! Now I talked to a couple of parents on their mechanical skills and here is what they told me. MORE GAS, MORE AIR, GET RID OF THE EXHAUST = HORSE POWER! Pretty simple Yes!

Now I thought the best thing was to go to my dealer ......wrong! Although they did help me get started with the use of their dyno at $50 a pop. So I made my own and works pretty well even if I do say so myself.

I moded the muffler like Nyroc's except I drilled 7 1/2in holes in the muffler and took out the baffle. On the dyno the power jumped to 9.45% on the bottom end and gained 6 km on the top end this is with stock air box and jets. I then tried all combinations of jets from dyno flow and the results were dismal. I tried the 132fr and 136r and there was only a 3.7% increase on the bottom end and 3 km on the top end. So as I said before more gas,+ more air, get rid of exhaust = horse power. So far I am staying with the stock jets, drilled some holes in the air box and the power popped up to 10.37% just by doing these simple mods excellent. Oh yes the fifth notch on the dyno flow jets don't cut it use the 4th notch and it is much better. I should also add I live in the 2200ft range and ride my green machine up to 9000ft so the stock jets work well but I will try 142f and 145r.

July 1st weekend I had the chance to race my friends with the 700's again and it wasn't even a contest! The only problen I had was with another Kawi totally bone stock and a modified 400 2stroke Polaris 4x4. I ate the Polarises, chewed them up and spit them out it was great. Bearman told me that the bike was down tune approximately 20% from factory and I can see this especially from the read outs I got from my scope. There is a definate timeing detune from 5000 rpm -600rpm the power curve is litterally flattened out.

There is great amount of potential for the 650 with just a few mods that are simple enough to perform and I still haven't had the chance to install the new snorkle from Bearman and give it a try. I here it helps imensly. If anyone is in the market for a dyno jet kit let me now I will stay with the Kawi jets at least for now. Something else you might find interesting; the larger the jet you use the louder the sound that will come from your muffler not much but noticeable.

 

Great Job alltoys!
Sounds like you have it all together! Just a question. This is the first that I have heard about drilling holes in the muffler and airbox. Are you talking about the muffler casing on the left hand side of the bike and drilling holes in the airbox cover itself? Does this allow too much dirt and dust into the airbox?

 

alltoys-- Sounds like a good start. That's too cool, the fact that Mike Penland is accessible and will help P-650 owners!
I too, plan on the "nyroc exhaust" mod and air box mod.

 

Alltoys,
that sounds great..just what I was planning to do..about the holes in the airbox, the right side is a no brainer, but the left side, is that only on the flat side up high facing the right side?, or all the way around the top?
The snorkle will probally make about 1 jet size diffrent than what Mike told me..
since his is stock..
I have the DJ jet kit as well..but the needles look real strange, that's for sure..
I'll probally use stock jets & needles..
The stockers would seem a bit easier for me to work with..
a pipe would do a lot, for sure.. as far as the filter, are you running a foam or k&N?
the jetting would be a little diffrent for each as the K&N probally flows a little more..
The stock needles & jets are the route I'm probally going to go as well..
I'm at sea level or so..so maybe I can run a little richer..or not..
I was planning on starting with the 142/145 as that is what I have..
and it ought to be a real close starting point..
keep up the good posts, & thanks for taking the time to do all the testing & let folks know
that for about 22$(filter) 6-12$(jets) 6-7$ (screws for carbs) $50 (snorkle) and some time,
this makes a big diffrence..

 

alltoys, very informative post!I would like to know how you built your own dyno.

 

See if I can answer some of this stuff you guys are asking. The holes in the air box are along the opposite side of the air box just above the air filter iself. I used a 9mm drill bit but 10 is okay too, like I say just along the edge above the filter and not along where the carbs are. If you happen to get some water in the box at least it will travel away from the inlet to the carbs and drain out from the box when it can. I was in water this last weekend up above the seat and water did get in the box but there wasn't enough to bother the running. Even the muffler was under water and I was wondering if the mods would affect the motor and if you manage to keep the motor running there shouldn't be any trouble.

I will keep my stock jets from Kawi as I beleive I had better results from them, more bottom end torque and top end speed to boot. The stock ones are 138f and 142r, trade the back one for the front and put in a 145 in the rear. To adjust the carbs although not balanced but it worked on the dyno quite well. Turn out the air screws to 3 turns and turn in the front carb untill the bike runs ruff then turn out till the motor wants to run fast and turn back in one half the distance between the two. For eg. if you turn in untill you are 1 1/2 turns from bottoming out and the motor runs ruff, then turn out till the motor runs wants to run fast say 2 1/2 turns out. Then turn in untill you are 2 turns out directly inbetween the two. This should be close and repeat for the rear carb and again you should be close. Not all bikes are created equal!!!

As for my dyno I had some rollers from a conveyor belt system four to be exact and they happen to be larger than the width of the tires around 16in. just worked out perfectly. I also had an auscilliscope I picked up from a TV rebuilding auction some 12 years ago I paid $50 for because it still has vacume tubes, old and heavy but useful. My wife I do beleive said what are you going to do with that thing, my reply was something intelligent like " you never now deer" I think that was the response at the time. Any way it has multiple graph overlay ability and 110,000 HZ capability what ever that means. I rigged up a hydraulic motor for the torque sensing part because as the motor turns it creats fluid flow as the rate of fluid increases so does torque and there is meter that on the system which can be tapped to input on the scope. For RPM I put a white line on the tire so a timeing light can strobe off the tire and using 12 volt to power the light it picks up the white line and of course if there is output it can be picked up from the scope. I also used a distributor off a high performance dodge 383 as It has dual point system to manage high RPMs as around 6000 - 9000 RPM. Most distributors can only handle up to 5500 RPM and the Kawi can if all reports are valid do 10,000 RPM. I used this system just to give me an average or hopefully more exact measure of RPM and possibly torque because the weights on the shaft have to measure inertia which can equate to torque and thereby HORSE POWER. Tim Allen eat your heart out. Also I rigged up a decibal gauge and vacume draw off the intake just to see how much the Kawi was sucking air and the findings were interestins to say the least. Now I did use the some of the results from my dealer's dyno to zero in my dyno and I can honestly say my enitial results were some 0.025% off that's close enough for me!!!! The only draw back was my Outaws wanted to launch the bike right off the rollers to somewhere out in space. So I had to use stock wheels on the dyno that's the only problem I had. With my stock jets, holes in the air box lid, and the muffler modded I acheived a respectable 10.37% increase in horsepower on the bottom end and 6km on the top end, not bad. My dyno cost me around $200 to biuld from spare parts around the shop and works well for me.

I hope this helps I enjoy tinkering as I am a machinist and welder. Nyroc, Monte, 1Bearman, and Mike Penland are very helpful and can answer pretty much any question you have. Its nice to read about these guys and be able to talk to a voice if you or anybody else needs help I will be glad to give you my findings.

 

Wow!!!!I am truly humbled.I think that building my own dyno is out of my league.

Thanks a bunch alltoys.

 

Hey alltoys, when I get to be on JunkYard Wars, I want to be on your team!!!

 

Truly impressive my friend! Glad to hear you are having so much fun! The muffler mod is definitely worth it's effort. It's quite a bit noisier than stock but man, does it sound cool!!!! I really want to get ahold of that new CDI box 1Bearman is working on. Once a guy gets the airbox mods done, the exhaust done, the jets and the CDI box, WE WILL BE UNSTOPPABLE!!!!!!!!!

p.S. CLUTCH MODS WILL HELP TOO.

 

Surveyor Good day! About your jetting question, if you haven't modded your muffler but your airbox jet down. The stock jets are rich to start with and work well with a modded muffler. Go with the dyno jet kit and start with the smallest jets. I say this because if your are rich to begin with and supply more air you still have to get rid of the exhaust. If you don't then the bike tends to run hotter. What will happen when you jet smaller without modding the exhaust you will run cooler but your power ratio shouldn't change that much. Which is good, start small then work up untill there is now more change in power and I would guess you will work up to 132f and 136r before there is now change stop. If happens before then all the better, as soon as there is no change then go back one smaller or leave it there untill you do some more mods. The stuff I have done is relitivly cheap and anyone can do it if I can beleive me can too!!!!!! The color the sparks should be is a straw brown color when you acheive this stop you are at the peak. Good luck in your endeavors, we don't do we don't learn.