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About harrperf

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  1. I grew up racing Cycle Ranch before joining the AirForce. haven't rode out there since Ian purchased the track until fathers day weekend. Was cool to see that HP was still around and building bikes!!!   I rode for "taylor Mx" back when he was out screwing people over...

    Hope all is well.

  2. No 200 testing The part has worked on nearly every application tested...it's universally a good product - and most notably is throttle response/acceleration - it flat out works great here. Depending on your tuning abilities - will determine how quickly you can hone in on final settings - but what works on stock - +10 numbers on main - +2 on pilot - and your very close. Hard to keep up on all the emails and posts - dont check TT to often any more - sorry on delay.
  3. We'd prefer to stick with a .115 outlet for a few reason down the road long term. The long short of what is happening is at idle and early transition the straight diameter of the needle is not blocking off enough flow of fuel. The .114 reduces this. If you do the area calcs - it requires a .002 larger straight diameter of the needle to achieve same change Testing of the product has mostly been done with 32:1 applications (really what most people should run for race/hard usage). And after doing some neat fuel flow tests with various premixes - I can conclude that mix ratio not only effects jetting - more oil makes it leaner - but also flow rate. And different premixes do the same. A quick fix for if you are too rich chasing your tail is to up your mix ratio - I run 28:1 in everything we race - but offroad guys this would be costly long term - and not necessary in tight trails. I believe we've gotten whoever needs a .114 taken care of - if not let me know.
  4. harrperf

    STIC metering block testing 17 300XC

    Fits the 36 My website has results on ktm 250 with 36mm stic Here is a video review on a ktm 300 There is another video of the smartcarb from same rider here I am am told the gas gas 300 REALLY LOVES the stic insert from a test report I have gotten
  5. Yes, you want more width one the early front - and it's built to compete with modern 250fs If it was made to be vs a 150f - it could drop some peak and add some width
  6. Use the air screw first. Nothing wrong with being 4 turns out for a day... But sounds like you may be a tad fat anyways in that spot.
  7. In total fairness this was a true stock ktm with maybe 2 mains leaner - I'd have to look. But I redid the test with a bored, tapered etc etc set up that really picked up! What I prefer to stress - is just how good it feels when you ride...that's what sold me on day 1. Like any carb - still has to be tuned in close - but the settings data base is growing by the day - and I think we have honed in some needles that will work well for the 300 owners vs using a smaller needle jet outlet.
  8. Huge thanks to Mog for posting his results - all of which he paid a fortune to publish. Like him or hate him - not many people on this forum pony up the cash or time to publish any real data. I with-hold most of our test data because it costs me a fortune - gives our customers an advantage, and most people "dont believe it anyways" when you show some bolt on sucks that they are partial to. I sell these STIC because of exactly what Mog has posted - it was a mind blowing experience when we first tested the STIC - enough that I have invested huge time in some changes for the production parts and also helped George to see the "light" about what some of the offroad guys are searching for (which was a great learning experience for me) The STIC performs BETTER on the track than the dyno suggests - which is what has me enamored with it to this day. How do you quantify some of these intangibles. The part throttle testing is one aspect - but its willingness to change rpm on command and "crisp" feeling are what are hard to quantify. This is where keefer's tested philosophy frustrates engineers - sure the dyno says this, but I feel that. The stic is a test riders "dream" and engineers nightmare - it performs really well - but is hard to quantify in all categories. It isn't universally a large power adder to all bikes at WOT - but it most definitely is a performance enhancer. So much so - I have said and continue to say - buy it, try it - and if you dont want it - send it back for a full refund. No refunds to date
  9. harrperf

    ISO Derek @ HPRaceDevelopment

    Since I'm absolutely pissed I'll reply I received a call at 5:40 am the other day from dave. I find this whole unaccepable of which I didn't answer. this was followed by a call at 7 am of which I did answer and told dave I would send tracking. Tracking was then sent the same day. I broke my windows 7 computer beyond repair recently and with it my ktm software. This is no longer available despite the fact I own the user setting tool.... I'm told due to EPA concerns (of which harley was fined massive dollars if you recall) ktm is no longer offering the UST. in order to ensure daves ecu was properly set up I had a friend in the business who I help when I can and who helps me when he can install my map file for me at his retail pricing. I was sent tracking of shipment of the ecu and sent that tracking to dave. while I truly wish I could improve anything the us government decided to do... I can't. until the postal service provides further update, both dave and myself are out of luck with the ecu tracking. I am currently part of a wedding this weekend for a best friend , which i may point out is the WEEKEND... and I feel it's entirely ridiculous to call me at 9:30 pm any day of the week let alone a weekend day. Your time could be better spent calling the usps and getting better info, maybe they can help you on their weekend time. Until usps reports back, I am in the same boat as you. It has been paid for and dropped off in the hands of americas finest post service members. Hopefully it's a computer issue or human error and it shows up sooner rather than later.
  10. Hey,

    So I would like to get a 2017 ktm 350 exc and would like to give it maximum torque.  Based on your posts I think the best option is the SXF header with the 4.1 slip on.  Of course I would remove all the smog shit, open up the airbox, and adjust the tps.  What are your thoughts?  Your messages are not working.

    1. harrperf


      I prefer the bills slip on a good bit.
      The rest might work out ok, but adjusting the TPS is a half ass attempt to richen the bike..a remap or a proper ECU would do wonders.

    2. skylerj


      I can definitely get a remap done. What header/slip on combo will give me the most bottom end in conjunction with proper mapping?  

    3. harrperf


      You wont get much with a pipe...it's just a sad fact.  I like the bills RE13 slip on - we have worked with them quite a bit and have a stepped core technology that really improves the "bark" and snap of the bike.

      The stock header provides the best power on the dyno - bottom to top.  The fmf looses quite a bit of bottom - and peak...a lose lose.

      You may consider a throttle body mod we sell - it's an improved air flow wing design - but a restrictor insert that increases velocity. Gains are great...but usually again requires some mapping to be perfect - although I have had it run well without mapping.

  11. harrperf

    STIC metering block testing 17 300XC

    I don't want to go too far into detail - but power instability is an unfortunate side effect of two strokes. Cyclical variation occurs between power strokes for a host of reasons - largely due to the fact the entire engine is resonating (from pipe to cases to inlet). It's also why I have stated fuel injection is a massive challenge on a two stroke (in pure performance applications). In addition - at part throttle the engine is far from "optimum" design. The inlet tract, reeds, case volume, port tunnel sizes, port areas, and exhaust system are all design mostly around WOT power - and not 1/8-1/4 throttle power. Trials engines are quite the opposite - designed for both a torque curve that is very flat - and that peaks early - as well as low throttle opening power. these engine has very tight cases, really low exhaust ports - and mild pipe designs. you Can jet areas so rich this doesn't become as noticeable something very common on stock KTMS...but then of course you are jetted rich. my engine simulation software shows this very clearly - with a SET AFR RATIO. AKA perfect carburation - there is still large variance in power per cycle in various throttle positions. At wide open power - its hard to notice a 1hp variation out of 45. but at part throttle - when you are asking the engine for 3-5 hp - .5-1 hp varation is easily noticed - and not a by product of fuel delivery - but rather power variation (which i real world means RPM variation)
  12. Society is getting dumber. Suspension is proof of this
  13. This isn't meant to be mean....please understand I really mean this in the nicest way possible. But lack of understanding is pervasive in this sport. Air is 78 percent nitrogen. 20 percent oxygen. It leaves 2 percent for other elements - lets call those insignificant (although next in line is argon at 1 percent - also inert and also a capable of usage in a shock or fork) You will not find statistically significant data that suggest oxygen expands significantly more to temperature than nitrogen ANYWHERE. it's just a fact of science. Expansion rate to temperature is well defined by the ideal gas law - for a set volume (what forks or shocks have) the pressure rise is Pressure = (nRTemperature)/Volume R is a constant for all gasses in this equation N is the number of "moles" captured in the set volume - the molar mass per set volume and pressure of nitrogen and oxygen is quite similar T is absolute temperature from true 0. If you bother to go through the equation - you will find that the pressure rise vs temperature of nitrogen vs air is nearly identical. http://www.barrystiretech.com/nitrogeninflation.html They did the math for you in above link. That said - highly humid air will be worse than totally dry air. But even still - it's a really small amount of difference between the most humid air possible and dry air. At 95F - about the limit many people ride at and fill their forks at trackside - it's about 3 percent maximum weight of water vs total weight of air...and that 3 percent in your fork will not reach a temperature high enough to cause massive issue. In the shock - it's more critical to be moisture free. I'm an advocate for practical improvement. N2 isn't the answer. On the normal aer fork - the balance chamber and the main high pressure chamber exchange pressure every extension. This means pressure rise is equal. Seems your works version has a massive flaw as it's building truly huge pressure. Maybe your better solution would be to start the moto off with air that is already at 100F - or closer to outside temperatures if you are filling it the night before or early AM with cool air.
  14. Nitrogen provides no improvement in pressure rise if the air you use is moisture free. And even with moisture the difference isn't huge. Nitrogn IS inert which provides benefits with oil oxidation and rust prevention...but that's about it. it blows my mind people continue this non sense... it's not hard to understand with basic research.
  15. I must not understand this cone valve air fork. I'd imagine the increase in balance chamber pressure would make it substantially softer. We must have a terminology mix up.