pittss1c

My plugs are pretty black after a ride... It might not be easy to get it into the sputtering state and pulling the plugs (it is rather intermittant...)

Hot Rods 4mil stroker 5mil long rod crank with Hot Rods pistons, noss cool head w/21cc stroker domes, cylinders have a mild port job. V Force 2 reeds, 28mm PWK carbs, DG pipes, dual carb mounted air filters with outerwears. THe mains are 172, and I believe the pilots are 55 (I haven't verified this) and the clip is in the middle.

I am not sure how to describe it. Normally when I give it throttle, it quickly and smoothly accellerates to the power band, where I hold on the best I can and try not to poop. When this condition occurs, the engine doesn't sound like it is firing all the time on both cylinders or missing some strokes, and does not ever reach the power band. If I pull the clutch in to bring the RPM up, it clears up and everything is back to normal. I have not yet seen the problem come back yet unless I slow down and drive slow/idle or go into the trails.

I have only a few rides since a series of enginge mods. near the end of the day on my second serious ride, when I gave it power to go up a hill, it sputtered and crackeled. Next ride I experienced the same problem intermittantly. When this condition occurs, if I pull in the clutch and peak the RPM, the problem goes away and it goes back to performing great, but will persist if I don't do something other than give it more throttle. Background: I think I have the mains kinda rich, but it seemed to perform pretty well, so I figured I would leave it. Most of my riding is done under half throttle, so I am not sure if the main jet could be the problem anyway. Needles are in the middle clip and the machine performs great 80% of the time. (even decent low end torque on trails) I thought maybe I was fouling plugs... They are pretty dark when I pull them, but I am not sure that means much. I don't have enough data to be precise (but do not want to burn my engine up collecting data)

I like the mod... I might buy a spare first. I haven't checked the needles yet...will do.

I can tell you mods that I was told at purchase. 4 mil hot rods stroker crank and rods... cool head with 21cc domes. 28mm PWK carbs, DG pipes, vforce 2 reeds. some mild porting. I'd buy a pingle right now to help eliminate it as a possibility, but don't want to lose the reserve.

It pulls well with either set. I expect to be running it at higher outside air temperatures. (these were done at 50 deg, and I expect I will run more often at 80) I am concerned that either the float level is incorrect, or maybe I am starting to run my bowl dry on the left carb during these tests.

I attached a file with a couple plug chops. The top 2 are 165s and the bottom 2 are 172s Both times the right side has a larger dark region and it varys a lot in width. The left side is more consistant. Any clue why? I am just trying to get it a little too rich for a starting point. I am told: The carbs are 28mm PWKs. 4 mil stroker +4 timing cool head w/21cc domes/ dg pipes/mild port

You were asxking which screw was which.... I am new and have the same carbs. I went looking and found this: PWK 28 diagram

I just have the stock petcock. I am wondering if that will fix the behavior at wot. For plug chop... warm up, put in new plugs, jump on and give as much throttle as possible and go through all gears till it tops out. kill switch and pull the clutch. remove the plugs. not quite WOT for 1st and 2nd gear...I am trying to keep the front end down. I am now just suspect that it might be running with bowls less then full bowls during the test (now that I know I can run them dry)

I did a plug chop, and one cylinder looked a little lean and the other had a wider band, but not very dark. Just for fun, I increased the jet sizes from 165 to 172 to do another test where I should be plenty rich. Well, I didn't feel like I lost any power, but now I am cutting out after running for a while in 6th at WOT. I am guessing that I am running the bowls dry of my PWK 28mm carbs. Should I assume any plug chops I do now are poisoned by the fact that I could be running lean due to a reduced fuel level in the bowl?

I wouldn't have bought them either (they were just on there when I got it) I have seen the graphs, but I am not sure how relevant they are to a significantly modified engine. Graphs for my engine with toomeys vs DG would be nice. (anyone want to loan me some) The fit around the petcock stinks. I will just have to wait and see how they hold up. They don't totally lack power. I am in danger of going over backwards in 1st and 2nd at all times with the flick of my thumb. Here is a recording It sounds a little deeper in the video then they do live.

I am just curious because that is what is on the banshee I just bought. I guess I am just curious what I am missing. Is it durability or performance. It doesn't seem to have much power after about 10,000 RPM, but that seems to be the case on other pipes too. I have seen many references to them sucking, but I have not seen much on why.

Well, I did my first plug chop. I am guessing it would be a funny thread if a few of us idiots posted pictures from our first plug chop. One side came out fine, and the other looked rich, but the accelleration really flattened out as the RPMs got high. I need to decide if it is a carb issue, a pipe issue (I have DG pipes), or a timing issue.

I am new to all of this, and have purchased a freshly overhauled engine with many mods. Before I go ride this thing, I want to see where I am at with the jets. I have read the plug chop method, and it appears you need to follow the instructions to a T to get an accurate read. You might find this funny, but I don't think I can get to WOT in the first 2 gears without ending up on my back on pavement. If I do the plug chop test and don't use WOT until I get to 3rd gear, will that invalidate the test? Also, what are the odds of burning up my engine trying to do a plug chop?