There's no stupid questions, just stupid people. ....help.

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quantum500
Posts: 193
Joined: April 21st, 2008, 9:44 pm

Post by quantum500 »

Have you ever tried wide open kill button depressed engine braking. Works pretty darn good. Another reason that its hard to squeak going down hill is your not generating much heat to break down the oil. Skiddy had a great question that no one answered I'm interested in everybodies opinion. The lean burn on the DT250 with no spark?
Ported&Polished
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Post by Ported&Polished »

teemtrubble wrote:I was being a smart ass "HELLO" someone pass Bob and Skiddy the box of "Summers eve" hehehehe :twisted:
Sweet! Smart ass remarks rule! But I thought summers eve came in a bottle? :P
Don't Clyde it, ride it!
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dannygraves
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Post by dannygraves »

quantum500 wrote:Have you ever tried wide open kill button depressed engine braking. Works pretty darn good. Another reason that its hard to squeak going down hill is your not generating much heat to break down the oil. Skiddy had a great question that no one answered I'm interested in everybodies opinion. The lean burn on the DT250 with no spark?
thats easy, it got so lean that something protruding in the combustion chamber (probably the plug tip) got hot enough to ignite. That why you don't run a head with damage on the surface becaus little chunks poking out can get nice and hot and ignite the fuel before your spark occurs.
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quantum500
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Post by quantum500 »

I understand the ignition part. Where does the extra revs come from? Any engineer will tell you that there is only so much available energy in gasoline. Here we have circumstances where it seems an extra lean condition produces more power out of the same amount of fuel. How does that work?
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britincali
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Post by britincali »

Lean = hot and in most cases hot = power, they just dont last long running like that :wink:



I had a YZ490 that would rev its balls off when it ran out of gas, the plug would start glowing so the kill switch was useless the only way to stop it was jam the back brake and slam it in second.
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quantum500
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Joined: April 21st, 2008, 9:44 pm

Post by quantum500 »

I agree they will not last long, but the fact still remains there is only so many calories in said amount of fuel. A engine could be designed to run at higher temps to use the extra lean condition especially for economy and possibly more power.
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dannygraves
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Post by dannygraves »

yes, but aluminum WILL melt! I've seen pistons with holes or even the exhaust side ring lands melted off :shock: they always say it ran awesome right before that happened :wink:
if we could use metals that can resiste higher temps and account for additional heat expansion, it would be a possibility, but then you'll melt exhaust, burn gaskets..... ya, probably not gonna happen. Stoich for gasoline is 14.7:1 if I remember correctly. if you run a motor under load WFO at 14.7:1 you'll start melting shit, especially a 2 stroke or forced induction application.
'09 kx450f 4-Poke
Gen-4 trail bike --SOLD--
Gen-3 badass trail/mx bike --SOLD--
Gen-1 built dunes bike --SOLD--
'05 klx110 --SOLD--
'95 pw80
Image
quantum500
Posts: 193
Joined: April 21st, 2008, 9:44 pm

Post by quantum500 »

Some diesel generators used for compressors on refer trailers use tungsten piston tops and sleeves. Thats 3000f + not the lightest material but interesting. Rumored to last over 100,000 hrs between service. There are also some Ti alloys that may work and lighten things up considerably.
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Skidmark
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Post by Skidmark »

I asked the "Old Salt" mechanic who's put a zillion miles on bikes that should have been crushed years ago (he showed me a clapped out BSA with over 200K on it that he rides to work daily!! And from the looks of it...never washed once.)

SO, back to my point....he also stated there is somethnig glowing in my combustion chamber and that what I experienced is REALLY bad. Temps skyrocket and if let to continue mass hysteria will ensue. It happened to me again today but I caught it fast enough.

Since we are talking about my questions that were never answered......
why does the bike fire every 5 seconds or so on decel with a solid DING and subsequent accelleration. $-strokes don't do that.

So why huh, huh, huh...why?

BRAAAAAAAP ! ! ! Going riding (or diving) tomorrow!!

"Skiddy" :shark:
I'd rather be riding right now!!!

1982 CBX six, 04 XB12S Lightning, 91 XR100R, 03 Yosh DRZ450S, 74 DT250A, 80 CR125R, 79 Husky CR390, 02 RM250, 07 LTZ90, 75 914 2.0, 08 Tundra5.74x4
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