Another jetting Question...

[JhallettEX]

I have re-jetted my carb, but I was wondering what would it do if I put the E-clip on the needle on a different groove. I am pretty sure that it is currently on the 3rd groove. What difference will it make when I move it either way? I am running a 170 main jet, E-series pipe, K&N filter with no air box lid, and a rev limiter. Thanks alot for your help.

[MARCUMS ATV]

You will probably richen it up a little too much. A 170 is pretty fat. You almost are bordering on jetting for a race motor. I would stay right where you are. Also check out the plug color, if it is very white you need to be richer.

Terry

[JhallettEX]

Thanks.....When I re-jetted it, it called for the 170 because I was under 3000 feet. If this is wrong and I need to change jet sizes let me know. Anyone else please help. I am running a E-series pipe, K&N air filter (No Lid), removed choke, re-jetted w/ a 170 main jet, and a WB rev limiter.

[Wheelie]

Is the clip in the stock position? If it's not, leave it. If it is, lower it one notch. Lowering the clip on the needle one notch will richen the mixture at low rpms and improve throttle response.

[JhallettEX]

Ok......Thanks alot, The needle is in the stock position. I will try and move it down another notch and see what happens. How about my jet size ? Should I change the jet size or leave it at 170? Also I am going to the track on Monday and I am planning on timing some runs to see what way is the fastest time. Is there anything else I should do or try? Thanks again for your help.

[carlj75]

jhallettEX: Did yours run fine when you followed the instructions that came with the jet kit? Because, I just installed the dynojet kit: 170 main, e-clip on 3rd notch, and mixture screw 3.5 turns out, and my quad runs like crap when I'm at full throttle. It feels like it sputters and wont go to redline. I tried adjusting the mixture screw in 1 turn-didnt help. I lowered the e-clip on the needle 1 notch-didnt help. Then I put the stock needle back in-didnt help. Any suggestions? I am running pretty much the same set-up: Megamax pipe, K&N with no lid.

[JhallettEX]

MIne is running just fine. I am just trying to fine tune it. i dont know what to tell you. Remember it calls for a different jet depending on what altitude your at. I would check it all over again. Also make sure you get your airbox tube correctly attached to your carb. Mine tends to slip off every once in a great while. Make sure it is really tight.

[Wheelie]

Carlj75-
Leave the needle in the one notch below stock position, and change your main jet to a 158 or a 160 and see how it runs, I think you're too rich right now.

[carlj75]

I let a friend ride it tonight, and he said that it felt fine. I think that I might be hitting the rev limiter. How would I know if its the jetting or rev limiter? It just feels like it tops out really fast in each gear.

[skemp]

It will get the RPM's up faster with those mods, carlj75, so maybe you are hitting the rev limiter. It will be like a rev-cut-rev-cut-rev-cut sound. I would compare it to a CD or record skipping or repeating over and over. Hard to explain, but easy to identify. It will be a repeating noise, as long as the revs are high.

With jetting, the problem wouldn't come with RPMs, but with the throttle position. It wouldn't be repetative as the rev limiter is, but more erratic and random. It might sputter here or miss there with jetting. Remember, the engine wasn't designed to red line, that is why there is a rev limiter.

Your jetting sounds pretty good, but might require some fine tuning. To me, it sounds like you are hitting the rev limiter, given the problem is happening only at the highest RPMs you reach. If however, the problem comes at 3/4 to full throttle, it is almost certainly jetting.