I am going to try to do all that before getting the bigger jug. I guess I over looked a gearing change. I just kinda got back into the bike after a couple weeks with an xbox 360. After modifying the firmware... it consumed all of my spare time. I was even bringing it inot work. I completed %50 of Saints Row at work!!!. Anyway, I decided I had to put the 360 away if I was going to get anything done.

I should be ordering up the pipe and carb parts by the end of November. . lots of people talk to me on the bike. They all say how cool it is and they want to get one. It is fun taking it through the drive-through...

 

Deleted.

 

Nobrakes, when you went with the 14:49 (my 49 tooth sprocket and chain should be here Tuesday!!) did you have to trade out the lower chain guide? I already took off the black chain guard as i know that wont fit (and fills with mud anyway..) but in looking at the lower white one today, it just seemed like it might be out of sync with that much bigger a rear sprocket. Did you have to make any modifications?? (Man am I looking forward to the torque boost!!!)

 

I don't recall there being any rubbing with the larger sprocket. The top one definitely has to go, but I kept the bottom one on. Maybe there was a little rubbing and I just didn't notice, but I don't think there was.

 

my bike makes me happy

 

Hey, don't knock Courage; that's some time well spent!

 

Mine too. But if we can have this much fun in stock form, just think of the possiblities[8D]

 

Wow. Where do I start.
I thing you guys have a basic understanding of what you are trying to talk about but you are throwing terms around with little clue as to their meaning.
I will start from the top.

Iowaguy:A 300 kit will make more power because power is a calculated from torque. You say it will make more torque therefore it HAS to make more power. I will also tell you that a 300 kit will make more horsepower(also calculated from torque). What is "horsepower momentum" anyway? Is that an Iowa localism for something?

Nobrakes: I think you are confusing engine power with applied power (torque, horsepower ..whatever) Changing gearing does not increase engine torque. It will only change your gear reduction/multiplication. That is why unless you need the really low gearing for slow trail work, skip the sprocket changes and just leave it in a lower gear. If the bike can't pull the highway speed you want in sixth, don't change your gears to put sixth in a better RPM range, just leave it in 5th. You accomplish the same thing for FREE. I digress.....
Iowaguy was talking about engine power. Again, speaking about engine torque, you can not increase it by changine your gearing. If you wish to stand by your statement for some reason, then, it is still flawed because you state that reducing gearing will increase torque but not horsepower. If you increase torque, you increase horsepower, it is math. You can not even measure horsepower. It is a calculation dervied from torque(which is the only thing you can measure): HP = (Torque x RPM) / 5252. Horsepower is a calculation that is used to determine an engine's ability to produce torque at a given engine speed...that is all.
Your mathematical formula for torque is correct. But, in that paragraph you fall back into your applied torque/power vrs engine torque power. An engine will make whatever torque power it is going to make regardless of what gear reduction/multipication apparatus you attach to it. Changing gearing does NOT change the power characteristics of the engine at all. Think of your statements about power etc as being referred to the crankshaft of the engine. No sprockets, no transmission, just at the crank power......... That is what you are talking about with bore, stroke, air filters, cams etc....

I hope I did not **** anyone off but for the uneducated, both of your arguments will be terminally confusing.

Here are two links I found that discuss the formulas, and explains a bit from a third party in case you think I am full of crap.

http://en.wikipedia.org/wiki/Torque This one is nice and technical....

http://www.g-speed.com/pbh/torque-and-hp.html This one is good also.

 

I'm not confused - power is power, there not some kind of "special" "applied" power or "engine" power for motorcycle engines other than the usual power. There is no need to confuse things with such terminology. Power is power, it has a very precise definition and can be measured easily. And then there is the drive train that gears that power down or up for the particular application - in this case, to rotate our rear tire.

Power is the basis, without power you have nothing. The power comes from the combustion of fuel in the chamber which drives the piston downward and the linkage with the crankshaft turns that into rotational energy to turn the gears. The drive train gears that power down to the appropriate torque for running our motorcycle - a rear wheel spinning at 5000 revolutions per minute would be silly - you need gearing to convert it to something more useful.

A particular amount of power can produce ANY torque - it just depends on how much it is geared. You can make a 50 cc minibike pull tractor trailer assuming you have it geared enough (and there is traction). Note when you change your front or rear sprocket, it either speeds up the bike or slows it down at a given engine RPM. This is a gearing change, and hence a torque change, but is NOT a power change. For a power change, say an increase, that would mean increasing the torque, while the engine RPM remains constant.

The 300cc (292cc) upgrade increases engine power, i.e., larger combustion chamber and more energy from the combustion which ultimately results in more torque at the rear wheel. This comes with NO gearing change. I.e., at 5000 RPM before, I'll be going just as fast as I was at 5000 RPM after the upgrade. The difference is, I now have more torque at the rear wheel.

Some folks have changed to a 13t front sprocket which gives them increased torque at the rear wheel. But the the POWER is the same, i.e., their 5000 RPM before is more like 5500 RPM afterwards, i.e., the engine is spinning faster and working harder to produce that increase in torque. With the 300cc upgrade, it is not.

Note that with improper gearing, you can't make effective use of the available power. This is one of the reasons people have changed the gearing on the KLX250S so that 6th gear has more torque. But the cost of that is higher engine RPM. The other approach is to increase POWER by upgrading the engine displacement. The net result is still more torque, but is done by increasing power, without the side effect of having to increase engine RPM to get it.

I hope this is clear. I know the terminology can sometimes confusing.


EDIT: BTW, Cowboy 6, if you reread what I originally said, and what you said at the top in your response, I think we are saying the same thing. What part of what I originally said did you find confusing or incorrect? I thought my terminology was accurate. Also, I never said changing gearing increases engine torque, you supplied that term. I'm talking about rear wheel torque here. Perhaps I should have been more specific with that, but I thought that was obvious since that's what we really want. One can measure the torque at the crankshaft, torque at the final drive output shaft, i.e., the c/s sprocket, or torque at the rear wheel. All these are different, but power is one thing and only one thing and changing the gearing in no way changes the power - I think I said that in my first post on this.