I think it is really cool when people are interested in learning new stuff. The best thing would probably be to find yourself a diagram or a cross section of a small engine on the internet and familiarize yourself with the different parts. I will always be at the mercy of someone else until I figure out how it works.

Trust me when I say you do not want to go around asking dolts such as myself for information on your quad motor all your life because at least 50% of my knowledge is certifiable crap and the other 50% just hasen't been certified yet![img]i/expressions/face-icon-small-wink.gif[/img][img]i/expressions/face-icon-small-happy.gif[/img]

Ron

 

Damn and I thought the answer was $$$$$$.

I remember when I was just young pain in the butt while in the pits at Englishtown here in NJ hearing two racers discussing the advantages of cubic inches v/s compression and HP between races, and the one guys answer always stuck in my head. He pretty much just said that cubic $$$ beats all, and the more of it you can add the faster you can go.

That may not really add much to the tech part of this discussion, but I think its still true to today, and controlls the limits everyone keeps questioning more than anything else.

Something I have always told riders looking for info on HP etc is that HP is nice, but Torque really moves me.

Now for a more serious question, since we have hashed some of the VE, compression, torque, and HP numbers and relationships of them etc does anyone know how to establish the longevity of the crank, rod or bearings when producing the additional power or energy?

I am currently working on a project to allow my engine to make the most of the comp is has (a true 12.6) and hope the hd head studs that just came in will do the trick, but now I am seriously quesioning the amount of time it will take till I will need to beef up the bottom end after it grenades. Any input on this would be appreciated, and the relationship of increased heat along with the increased energy from the compression would be great too.

Sorry its not on a DS but an engine is an engine right

 

I don't think an engine is an engine......... That may be the stupidest thing I have ever said[img]i/expressions/face-icon-small-disgusted.gif[/img] You tricked me into saying that didn't you?

The Rotax comes right from the factory ready to almost double its hp without worrying about things such as tranny's or additional cooling or crank or rod life. A YFZ450 motor comes from the factory compromised in half of those areas even needing a piston after only 100 or so hours, etc. etc.

I can't speak to your motor (400EX?) but part of the DS advantage is you have so much baseline durability right out of the box.[img]i/expressions/face-icon-small-smile.gif[/img]

 

I understand your point, but I meant as far as std things like mods to the bore and stroke, or compression goes in creating power and increasing stress on the other engine componets.

 

I didn't read the whole thread but i have one question this one is serious. Say there is a bike with 62 lbs of torque i guess were talking rear wheals. is this with a small rider or what. i wouldn't think that the bike would have the same amount of torque with a 200 lb rider as compared to a 300 one, just curios if that changes the torque and then how would you calculate it?

 

2big, based on what I have found that number will stay constant. The weight factor increases drag and thus makes the bike work harder to do the same. I am in the same boat as you, as I am at that horrible 300lb number myself. I am trying to learn, and find how the numbers work with the different mods available to really get the best bang for the buck.

 

Boys, All you have to do is cut the bike down to hardly any weight at all and then you will feel just like your flying with all the torque that your bikes are making. [img]i/expressions/face-icon-small-wink.gif[/img] 2Big will ride my bike whenever I come out and he will give a full report, [img]i/expressions/face-icon-small-happy.gif[/img]

 

The bike and I are going on a diet together, doubles the losses [img]i/expressions/face-icon-small-smile.gif[/img] The kind of riding I do, I can't take her down too low or she would never hold up.

 

I understand about the different riding conditions. All I have to do is throw the dune shocks on and I will be set. [img]i/expressions/face-icon-small-wink.gif[/img]

 

I would be scared to jump that bike Choose. My fat **** would snap the frame [img]i/expressions/face-icon-small-smile.gif[/img]