Any Dyno Results on "Burned" Bikes?

In another thread, it was stated that a stock S has 38.4 HP, and with the Yosh exhaust (loudest) it is 41.5 HP. Burned, do you or anyone else have Dyno results from the following generally accepted mods: :)?

- 3x3 airbox mod

- Stock 142.5 Main Jet

- Dynojet 25 Pilot Jet

- Dynojet spring and needle (4th clip position)

- fuel screw out 2.5 turns

- Exhaust restrictor drilled

I run the same setup as yourself. I think the DynoJet kit even came with a coupon for a free dyno run. I suspect the reason that few S rider bother to dyno their bike, is that we aren't setting up competition bikes. So, we tend to be happy with "better" power, and good jetting, as oppopsed to MX racers who are obsessed with finding "best". Because we all know that an extra 1/2 hp will put you at the top of the podium everytime. :)

I think those HP figures are for the E and kicker models.

Cycle World tested the stock S at around 33hp so with rejetting and a pipe perhaps around 36-38.

i do have many graphs,but im not going to get into posting them.i use the dyno inconjunction with a exhaust gas analyzer to obtain the correct jetting.

every dyno is a different animal!not to mention the different brand of dynos out there.the room set up plays a big part of the numbers.the kind of tire a bike has affects it,the drum wear,conditions.to many variables to compare with somebodys elses numbers across the country.

i have to this day refrained form getting into dyno graph wars.its no win situation. :)

maybe somebody else will post some graphs.

horsepower gain claims are a flame war waiting to happen.sorry.

Dyno results are only accurate on the day they were run. It's a tool to dial in your jetting, not a benchmark that a guy in Colorado chases, when he sees that a fella in LA got 40hp on his particular run(s).

As well, I don't think you can really do much with just one run (that you can't feel in the Seat-of-your-pants). If there's a huge flat spot, you'll feel it. If you want to get "best" jetting/power you'll need a notebook, a pocket full of jets & series of runs (one after another).

Burned's setup was good out-of-the-box. The bike is jetted better than I ride, so I know where "MY" R&D needs to go.

Thanks AGAIN, Burned.

I'm not interested in starting a flame war. Really, my reason for asking was actually in deciding whether to invest in a slip-on. I haven't actually done any of the above mods yet, just weighing actual gains opposed to money spent. I agree with the seat of the pants analogy based on my experience with other bikes, mostly street.

Here may be a more appropriate question....Based on "seat of the pants" feel comparing before and after the aforementioned mods, how would you describe the diff? More low and midrange pull, 10% gain maybe? Roughly the same top end? Less top end?

That's gonna mean more anyway than a number.

I have run Dyno jet dynomometers for about 10 years. While it is true you can't compare sea level to 6000 feet runs,(there is more air available at sea level). Running a controlled test, at SAE corrected will give you fairly accurate and comparable results. There is something to set up though. Proper tire and pressure, chain adjustment etc. all play a part in setting up before a run. I've never had problems with drum bearings or anything like that. Jetting the bike correctly will yield big gains.:)

A lot of that 'seat of the pants' feel is dependent on what type of exhaust you purchase. Like on mine, I run the PowerCore IV with a PowerBomb header. This header is tuned for more mid/low and feels different than their straight-through header. What type of riding are you going to be doing, wide open desert where power up top is paramount, or woods where low-end grunt is more important? My point is make sure you get the system that will most closely match your riding style and terrain. Not all exhausts are created equal. IMO :)

I ride mostly fire roads and open trails, some moderately tight trails, but I'm not trying (yet) to decide what pipe to purchase. Rather, I am trying to decide whether to purchase one at all.. That's why I'm asking about "seat of the pants" feel of the above mods compared with stock. I would really like to consider myself finished with the above mods. Can anyone answer this question, or do I have to trial and error? Come On....

Originally, I ran a setup suggested at Thumper Racing (3X3 hole in top of air box, 150 Main, 27.5 Pilot). This was an improvement over the stock setup. I left the exhaust completely stock. This setup was good, but I felt a mid-throttle surge that wasn't solved by shimming the needle. So I went to the DynoJet kit for the adjustable needle.

The DJ kit (and Burned jetting) gave a much improved pull at mid-throttle. I'd say that for whatever improvement I got from the Thumper jetting (over stock), I feel I got that much more with the DJ kit (over Thumper Jetting).

Numbers? Percentages? I dunno. With each setup I felt an improvement. I'd say that if you go from stock directly to the DJ kit (and Burned's setup), you would be very happy. Installing an aftermarket exhaust? Not for me. I think you'd get more bang for your buck with an E carb.

DR, If you want to know do it and tell us ya lazy bastard.

Next you'll be asking Burned to come over your garage and change your oil.

Seek and ye shall find. :)

Oh ya, a 14 tooth counter shaft sprocket also helps on the trails, and will only cost you $15.

Some guys have run a 13 t, as well.

I did the pipe and jetting at about the same time. To me, it was absolutely worth the $450 or so for the exhaust. It ran better/harder right after I changed the pipe (prior to the airbox/jetting mod). I had to change the jetting right quick cause it was very very lean..... lots of popping and crackling on decel and even on gear changes. :)

This could all be in my head, but I don't think so. :D

Now that's what I'm looking for....Thank you. Curious.....Why are aftermarket pipes not for you? I think I agree, but curious about your reasoning. Also, regarding the E carb, isn't that like a $1200 add-on? I'm in GA. That would be like six trailer payments.

beezer....what can I say? Your input is appreciated, but I can't let your comment go without a response......Other listers....please tell me if I'm out of line.

I'm not lazy, but trying to learn from others who have been there done that. I'm willing to learn from my own mistakes, but would much prefer to learn from others who have gone down the road before me......

To sum it up.....I'd rather be a lazy bastard than a dumb bastard. Thanks for getting it right. :)

Historically, lazy people have been the true innovators. We find easier, faster ways of doing things so that we have more time fo fart around on TT!

:):D :D

you should have just asked DR!i would have told you what you wanted to know!if noise isnt a issue for you by all means go with a slip on or full system.the peak horsepower gain will be around 2 h.p.,2-4 more with jetting depending how you go about it.but that doesnt tell the seat of the pants story.it will rev so much quicker with a after market muffler you wont believe it!imho if you go after market,go with a full race/open baffle.if noise is a issue,stay stock.

i dont mind answering q's,just dont like dyno graph wars.been there and done that.

ive been asked several time lately what my bike dyno's at.i would tell you guys but i would have to kill you! :D

alot!,how that? :)

I'm in California, and sound testing is becoming the norm. The "BRRAPPP!" of a Yosh will definitely get you noticed, but it's simply not the kind of attention I want.

I think there there are good slide carb kits avail' for around $500, but someone else will have to comment on that. Plenty of other guys have done it, and reported big gains.

A couple reasons for keeping the stock carb would be the CV carb's tolerance of altitude changes, and the increased gas mileage (for big rides). My current jetting still gets me 50+mpg on the street. I think that E bikes get something more like 32-34mpg. There's no free lunch, is there :) ?

DR, I was kidding you.

Changing brass is not major surgery, you can always go back to stock if you keep records.

You don't need a dyno, your sitting on one right now.

Hey Beezer, I was kidding too....There's nothing I dig more than a spirited discussion......The re-brass IS major surgery for me though. I have not done it the first time yet, and I can't justify (honestly) taking a chance with it over paying the 60 bucks at the stealer.

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