J-Madd

Yeah, on flat ground, but I'd been flying down a long gravel. I guess each time I pinned the throttle it sucked a little more gas than it let back in while I was off the gas. After a mile or so, it eventually drained the right carb, I guess. A contributing factor is likely the billet gas cap. It flows air fine, but I don't know if it flows fast enough for this motor. I took the cylinders off and it just looks like melted aluminum that can be taken off, but no one around here is familiar with nikasil, so I'm just shipping them back to Jeff today. In the future, I'll never ride that far at or near WOT again. I'll probably get the billett bowls, even if I'll never need them again. Thanks all. I hope this thread helps others keep this from happening. Live and learn and open up the wallett!! ::

Thanks, I'll let you know.

I was running +5 degrees timing advance, and it ran very smooth in 6th gear, revved out well with heavy red label wheels and 22'' realtors. I installed a new billet impeller when I built this motor. I opened the radiator to see if it was circulating, but I couldn't tell because of the motor vibrating the water. I rode a good while before this happened, and it never seemed to overheat. No puking of anti-freeze or noise when I shut it off. As far as the cylinders, I guess I'll send them back to Jeff, then he can forward them to whomever. I was just hoping I could send them straight to the 3rd party myself to cut back on turn around time.

That's exactly what I'm going to do. Anyone know the quickest place to get new nikasil on these cylinders, assuming they're scarred beyond honing (I'll know tonight; too disgusted yesterday to work on it.) How many people have ran these things out of gas? I read a thread last week where a guy ran his brand new Cub out of gas also, but he just lost compression. I guess it's easy to underestimate how fast these monsters pull gas out of the carbs, versus how fast gravity can feed it in.

I just tightened the studs until they felt snug. If you go too far, there won't be enough threads above some cool heads, but if you don't go far enough the stud will come out when you try to loosen the head nut.

Well I had a gutted out stock cap before I built this 4 mil, but now I have a billett aftermarket cap from modquad (which doesn't flow as much as the gutted stocker) but I can blow air through it easily, but the way this thing sucks gas, I could see that being the problem. I used almost a half a tank in 5 miles and most of that was going slow through trails, only a couple couple miles of wide open gravels.

I have a pingel. Surely I couldn't have sucked the bowls dry. But if that's what happend I'm done riding this thing on long roads. I'll stick to drag racing instead of riding down long roads, but it was fun going 90+ on gravel. Edit: I thought the pingel was listed in my sig, but it's not.

Doesn't the cable still have to have a threaded piece on the carb? That's weird. I've had a twist throttle and the only difference I saw was the threaded on that went into the twist, rather than the thumb throttle. Not questioning anyone, just submitting my experience (from what I remember.) edit: I did not have a 2 into 1 carb. I'm sure that's the difference, but I'll leave this post here anyway.

As mentioned, I'd just buy a new dome. I ran a pitted stock head once that had compacted metal in it (wrist pin clip) and it came loose and ruined my piston and cylinder. It ran awesome before that happened, though.

Different carbs were on the other locked up motor. Running a stock gas line on one carb, and a tad bigger line on the other both times, though, if that matters. I don't see the bowls running dry, with burping the throttle every 3 seconds or so, but I'm open to anything to not let this happen again. This was not the first time today that I'd halled ass a few miles, 3 seconds at a time, but it was a little cooler outside when it locked. I tried to post a pic of my plug chop before I rode today,but the file was too big. It was tan with at least 2mm band.

I second that. There is no way that the Toomeys pull less on top, unless you are way lean (or have very low compression, compared to when you ran the stock pipes). Take off the lid, put on a K&N, and put in some 330s to 350s. I ran 350s with this set up. Rich, but halled ass past every piped Banshee or YFZ it ever raced. Probably 5 or 6 of each, beat'em EVERY time.

Enter exactly what is on the pistons in quotations on google and see what it comes up with. That's what I had to do for some pistons, but they happened to be wisecos. Yours are not, it seems.

I have cut the wires and spliced them before. The colors are the same, I think. Was not my Banshee, but I it worked.

Ring clearance was within tolerance, squish was 0.045", compression 180 psi running 108 octane Klotz fuel at 32:1 with super techniplate. These are (were) brand new cylinders.

This is a brand new crank/bearings. This sucks. Any idea why this would happen in the first place? Is it not safe to hold it WFO for a few seconds then let out and get back in the throttle? That's how I've alway ran down long straight roads, even on 4-pokes.

It had to tear it up to lock up a cylinder, right? (at least the other motor did) How thick is the nikasil? Is it possible to hone out the scratches, or bore it at all it the scratches are very deep (which I'm sure they are.)

Jetting was ok according to the plug chop I did, but it locked up anyway. I was going down a gravel road halling ass 6th gear WOT, but I'd let out every 3 seconds or so and get back in it. I let out to take a curve and went back on the gas and it locked up. this happened to me on my other Cub motor over a year ago and I called it a cold seize, but this motor was warm and I'd went 3 miles or so when this happened. (172 mains in 39 mm pwks, temp 45, alt 300ft) I haven't tore the top end apart, but I know what I'll see. What are my options here. You can't just bore and hone these cylinders can you? If that was the case, I'd have this fixed in a couple days with a fresh bore and pistons. Please advise!!!!

Thanks everyone. It looks like I'll take out the bad link (and another link?) and run 2 master links.

I was cutting a new chain for a +4 swingarm (392 Cheetah Cub) and almost took out the wrong pin. The pin that we marked was on the half of the link that did not contain the roller. In other words, if this pin is removed, your left with an open end to the chain that only a half link could fix. But I noticed this before the pin was completely removed. It was only partially pushed through, so I put the chain in a vise and pressed the pin back in and hit the ends of pin to flatten them. The roller is slightly loose on this particular link. Should I: 1. Run it like this until it stretches enough to remove this link entirely? It would not have to stretch far. 2. Put a smaller sprocket on the back and remove the link. 3. Make the chain were I can use 2 master links. 4. Buy a new chain and start over. Thanks.

I've found the clutch pull with an easy pull lever/perch and hydraulic clutch to be basically the same. My Magura's slave cylinder took a crap after about a year, so I went to the easy pull for a fraction of the cost.

Are you running the stock gas cap? It can restrict flow of air, thus restricting the flow of gas into the carbs.

Well, I finally rode it briefly. It IS difficult to shift under power, but I only made a couple passes by my house on rough ground. I could pull the clutch in without problems, BUT on the rough ground I couldn't hold on good enough to use my whole hand to pull in the clutch enough to shift it easily. I think it will be fine on smooth ground. I cannot believe the difference in this motor and my stock stroke Cub. It feels like my ass is strapped to a rocket!!

Glad you found it. But to answer the question, yes you have to have the washer. When you tighten the main, it actually holds the needle jet in the carb body. Otherwise, it could move up the needle.

Not sure what you mean by bearing pins. The c-clips are in the grooves in the case, if that' s what you mean. The crank didn't have those pins in the middle like the stocker. I'm sure it's all together correctly. I followed the Clymer's, but I have a bad habit of drinking a few too many Miller Lite's when I work on it. When I know I've had too many, I work on something simple, like throttle cable installation, instead of piston c-clip installation Thanks

JUST a lockup; no override. I hope I don't regret that. With +7 timing will it overheat if I just ride around while not drag racing (trail riding)........I know trail riding is not what I built it for; but it'll happen every once in a while.