Plug Chop Pics. Need Some Opinions.

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KanuckKDX
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Post by KanuckKDX »

I don't want to hijack but where can I get the lowdown on "plug chopping"? I mean simple and detailed. The whole thing. "PLUG CHOPPPING 101"
KanuckKDX
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canyncarvr
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Post by canyncarvr »

PLUG CHOPPING 101 (clicky)

Well, sorta. Pretty close.

You will have better luck cutting the threads off all 'round I think. The 'chop' part does include clutch in and engine stop...but also throttle 'off'.

I think the color (..if darker than chocolate...) comment is bogus. The color will be darker if you run it longer. It's the 1-2mm part that matters.

Keep in mind that is testing only the main jet. There are still needle selections, needle clip, pilot, air screw and throttle valve choices to be made.

Start with a clean air filter......

btw...it came from googling 'plug chop'.

btw2..I think the link is in reference to Banshees.....not that it matters.

Consider the source
Using a perceived level of knowledge to boost my self worth.
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jafo
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Post by jafo »

In general, jetting by feel I've done many times on car engines with good results and in no way close to damaging the engine if you have a good starting point. Basicaly what I've done was from the begining when I got the bike, I put the pipe on and it recomended to richen the jetting to acomidate the FMF pipe. I know some guys that used to ride KDX's that have put FMF pipes on and not changed the jetting, leaving the stock jetting in place with no troubles at all. I did richen the jetting up alittle when I put my FMF pipe on and also the Delta 3 reed system. They ran the stock read system thats why I played it safe and jetted richer on my bike. Now after running it this way for a few months, I decided that my bike was'nt getting the hit it should have down low to begin with, as well as throughout the rpm band as I found later on. So I started this jetting thing awhile back to get the power oput of the bike I thought it should have while eliminating some if not all of the spooge that I could. So my next step was to try to drop the jetting size to start leaning the bike methodicaly and slowly to acomplish all of this. So I did drop the size and rode the bike as is for a few more months. Getting more knowledge of how other bikes perform while riding, I decided it was time for another jetting change. I decided to drop the jetting again to the next size down leaning it some more. It gave me great results. So this is where I'm at now. I'm still going to try another plug chop this week and see what it looks like. The spooge is all but gone, as you may have figured, spooge is a big deal with me. I mainly ride with mostly with guys who run 2-strokes. I don't see as much spooge with thier bikes as mine and when getting home my back was covered with it and so was the bike, so bad it was that it ran down the length of the pipe dripping down onto the swing arm and pooling. It now leaves just a residue around the arrester opening, thats it. I can live with that. But also my concern is making sure I don't do any damage to the cylinder or engine. I figure if it was going to blow, it would have blown Saturday. I got pretty rough with her on some semi-technical hills. I even ran it out of gas once. I've jetted cars by feel before and can notice the loss of power right off the line and know that the jetting is to lean. I think that jetting between cars and bikes are alike in alot of ways and I can notice small differences in the bikes tone and power right off as well as how it starts, just like with a car engine. I guess you summed it up Ski, I like to ride and tune by feel but I like to also rely on the technical aspect of tuning also to make sure I'm in the safe zone. So like I said, I'll do another plug chop tomorrow to see where I'm at. I just have a feeling that this is probably as far down the jetting chain I want to go until my carb mods this winter. Won't be doing any riding before long anyways. I appritiate everyones input tremendously. I'm still learing about bikes and the ins and outs of tuning, but I'm getting the feeling for it.

Charley, the ground strap is'nt the part thats wet with residue, but the lower part of the threads. The strap is pretty clean. After a days riding Saturday I pulled the plug and it was dark from the grounding strap down into the porcelin and dry, but the lower threads of the plug were and have always been wet with residue. I now run Bel-Rays Synthetic 2-stroke oil at 40:1 mix. Gap the plug at .028 and run a NGK B8ES plug. It's been so long since I've played with the different heat ranges of plugs but I think this a little hotter plug than stock but don't remember.

Jon.
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