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About smcdonn

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  1. There is so much bad info in this thread. So let's say that you can only inject fuel while your intake valve is open, in theory that's 25% of the time on a 4 stroke right (I'm not going to get into cam timing as its actually more but lets keep to theory). So maximum duty cycle would only be 25% if you never wanted to fire onto a closed valve. On a properly designed EFI system you will have a max duty cycle around 85%, please explain how this bike isn't firing fuel onto a closed valve??
  2. Been there done that. I used Sportdevices.com for my data acquisistion. Stay away from trying to make an absorbtion dyno, controlling those gets very difficult.
  3. smcdonn

    asf treatment

    Micro-polishing the tranny has benefits, they are minimal at that but if your a factory team trying to get every last drop of power to the wheel it makes sense.
  4. Give it a try. Your right it can't do much harm, but the flip side is it sure won't do much good.. Your wasting your time to be completely honest.
  5. smcdonn

    High Compression.

    If you understand some thermodynamic terminology, I found a pretty good read. http://www.chemcases.com/fuels/fuels-c.htm
  6. So if the capacity of the bearing is 1k lbs, and you have 2 bearings that means you can support 2k lbs.. You are going to run bearings in both sides correct? Also don't forget your front wheel only supports half the weight of the bike (there are some assumptions here), until that is your doing stoppies!
  7. There is a reason for that, "wall wetting", "accel enrichment", are all terms to be associated with why it does this. Fuel injection is no different, when you crack the throttle open on a FI bike it's "dumping raw fuel" just like a carb except it's being done electronically. Yes you can definitely refine the FI quite well, but like Gray said, thats why they have leak jets.
  8. Fuel injection is really not any more efficient thermodynamically. Fuel injection is capable of fine tuning on the fly which a carburetor can not do which makes it more fuel efficient as a system vs. a carb.
  9. smcdonn

    Hour Meter Mystery

    You guys are way overthinking this.. Horsepower hours? Sounds like "Work" to me. Work IS directly related to fuel consumed assuming constant thermal efficiency (pretty good assumption). So fuel consumed would be a pretty solid measurement for when to change your oil..
  10. Many OEM's use micro switches, problem is that if it wasn't originally designed for one, it's much easier to use the banjo pressure switches than rig a micro switch..
  11. Imagine if your rear wheel was actually a sprocket, and the road was a long chain. A zero slippage scenario would yeild a certain maximum acceleration of the rear wheel with respect to speed (wheel rpm's). The next closest thing to this would be measuring the same thing with a street tire on the road, measurements should be very similiar.. Now you have a baseline for the most traction you could ever have. All you have to do now is compare the acceleration of the rear wheel at a particular speed to that of your best case scenario. If your motorcycle only has say 50 hp, with perfect traction there is a maximum acceleration the rear wheel will have at a particular speed, any acceleration higher than that of the theoretical limit would mean there is slippage.
  12. In general I think the general trend your going to find is that larger mufflers are needed as performance goes up if you want low noise output. If you look at OEM and the aftermarket, the trend is the same. No one has really come up with a "silver bullet" on damping sound with performance gains, it's one or the other. Unless your willing to compromise going to a larger muffler..
  13. A piece of tape cost you .2 hp?? I have built, and operated dynos and I just can't see a piece of tape affecting a HP reading.. Sorry I just have to call BS
  14. Well if you know what they are NOT about, why don't you explain what they ARE about... Telling someone they are wrong with out explaining why is about as useful as well, me rambling...