IVIayheIVI
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Now... I'll be the first to admit that I'm no mechanic. I have some mechanical skill from working on the farm and that's largely from maintenance work on larger vehicles and equipment. I never had to do any sort of work on my dirt bike engines.
With that said, I just finished reading a bunch of articles in regards to power band. I was one of those noobs who did think that "powerband" on a bike like my CR250 was a mechanical part or parts in the engine which produced that large, sudden increase in power at higher rpm. What really engrained this in my mind is the fact that my little MX80 did not have that noticeable increase.
From what I've read, and I hope I've got it right this time, my CR250 had that boost effect largely because of the tuned pipe. There are other factors such as the reed valve but the pipe does most of the work here.
My MX80 was an oil injected 2-stroke. It did not have a pipe design like my CR250. It performed more like a 4-stroke as there was not a significant increase in power at higher rpm.
So the Jetpro added that high rpm tuned performance like I experienced on my CR. That's cool. However, it didn't satisfy my desire to have more low end power. I LOVE climbing with my XT. I find myself a big pile of dirt or a cliff and I go for it. With the Jetpro, I didn't get to the real power when I was climbing.
Without sacrificing the top speed of my XT by changing gear ratios, what can I do to get more low end power for climbing? Seems to me I read that DDM's Dominator is better for low end, Jetpro better for high end, but DDM doesn't make one yet for XT's as far as I know.
I'm wondering if a straight pipe does allow for better LOW rpm performance over a tuned pipe as the backpressure might be working against the engine to some extent until it reaches that sweet spot in the higher rpm range. The exhaust port on the engine is much larger than the hole at the end of the Jetpro. If my thinking is correct, this restricts the engine's ability to expel exhaust and obtain fuel mixture at those lower rpm's. I would really like to get some feedback on this theory as again, I'm no mechanic and I'm really trying to learn how this all works so I can get my XT running how I want it to.
The fact that we don't have multiple gears in these rigs really restricts our ability to take advantage of a tuned pipe, keeping it at that high rpm range through multiple gears.
Your feedback is welcome and appreciated!
With that said, I just finished reading a bunch of articles in regards to power band. I was one of those noobs who did think that "powerband" on a bike like my CR250 was a mechanical part or parts in the engine which produced that large, sudden increase in power at higher rpm. What really engrained this in my mind is the fact that my little MX80 did not have that noticeable increase.
From what I've read, and I hope I've got it right this time, my CR250 had that boost effect largely because of the tuned pipe. There are other factors such as the reed valve but the pipe does most of the work here.
My MX80 was an oil injected 2-stroke. It did not have a pipe design like my CR250. It performed more like a 4-stroke as there was not a significant increase in power at higher rpm.
So the Jetpro added that high rpm tuned performance like I experienced on my CR. That's cool. However, it didn't satisfy my desire to have more low end power. I LOVE climbing with my XT. I find myself a big pile of dirt or a cliff and I go for it. With the Jetpro, I didn't get to the real power when I was climbing.
Without sacrificing the top speed of my XT by changing gear ratios, what can I do to get more low end power for climbing? Seems to me I read that DDM's Dominator is better for low end, Jetpro better for high end, but DDM doesn't make one yet for XT's as far as I know.
I'm wondering if a straight pipe does allow for better LOW rpm performance over a tuned pipe as the backpressure might be working against the engine to some extent until it reaches that sweet spot in the higher rpm range. The exhaust port on the engine is much larger than the hole at the end of the Jetpro. If my thinking is correct, this restricts the engine's ability to expel exhaust and obtain fuel mixture at those lower rpm's. I would really like to get some feedback on this theory as again, I'm no mechanic and I'm really trying to learn how this all works so I can get my XT running how I want it to.
The fact that we don't have multiple gears in these rigs really restricts our ability to take advantage of a tuned pipe, keeping it at that high rpm range through multiple gears.
Your feedback is welcome and appreciated!
