J-Madd

The track didn't have 60 ft beams, and was so shitty and bumpy that I couldn't go straight on most passes. I don't have any useable feedback yet. Going to an all day test and tune session at a good track in a couple of weeks. If I get time, I'll get some back to back passes with different pipes. I have a few more bikes I have to get dialed in first.

I don't see any reason peak power wouldn't be gained with the Vito's pistons. It's like raising the exhaust port. Whether it's 8 hp, I don't know. Probably depends on the pipes, and if they like the higher exhaust port duration.

Yeah, I bought a set a few years back also. At least I've never bought a boost bottle.

Why do you want to run the spacers anyway?

That is gonna be a handful on a stock chassis. For comparison, I had a 14 Mil Cheetah and ran 76 - 77 r/o 14 Staggered extremes on a stretched stock chassis with a +12 swingarm; 16/43 Gearing, launch in 2nd. You may try 16/44 or 45 with your weight There's no way I'd ride that with a +6 arm, even with a bar. I broke a wheelie bar and the bolts in the struts (twice) because it launched so hard on the bar. Those bigger (relative to the Cub) motors feel so much faster, and have so much more torque; even when they don't lay down good times. I can ride a 14 Mil Cheetah and run 3.8s or run a Cub and run the same time, but the bigger motor reacts completely different (in a violent way), but that could have been in the chassis setup. Good luck and be careful! This was mine.

Well, we actually raced in Kentucky. The track was not prepped well for a ridgid, and there was not enough shut down room. My best pass was 4.39 @ 55 mph, lol. We were letting out after half track. My crazy brother actually ran a full pass; 4.02@82 mph. I don't know how he got it stopped (that bike should run low .80s at other tracks, though.) Well, back to the pipes. Here are some more pics.

Yes, unless the plating is damaged, just put it back together with new pistons. What size domes are you running? You should've checked compression on the old pistons so you would have a baseline to go by. On the latest Cub I rebuilt, the new pistons and rings only brought up the PSI by about 5. The motor was ran hard all last year at the track and even had some deto while on the dyno, but I didn't change the pistons.

Well, the piston hitting the plug could obviously shatter a spark plug also. Didn't know a torch would shatter porcelain though. How hot does porcelain have to be to shatter? Does an engine ever get that hot without detonation or preignition?

You don't usually have to hone nicasil at all. Also, what were the numbers on the old pistons? Are you running a stock rod length crank or + 5mm?

I guess they have a monopoly on the paddle market?? Can you buy the paddles separately?

Will post more pics when I get them installed. I'm going to a track I've never been to tomorrow, so I don't have any times to compare them to vs SHearer. I plan on getting them on the dyno vs. RDZ, CPI, and Shearer. THe quality is excellent, and I'll find out later if they mount easy.

Those tires will be perfect for you.You're correct, they are directional, but run them against the arrow with about 2 lbs in them. Be careful with the stock swingarm though. You may have to regear because the Pro Wedges are 22" tall, and swell up a lot more than that on top end.

If its a lever it will work. One way will be closed, the other way will be open. You'll just have to figure out which way is on or off. The blue wire is for the voltage regulator (goes to the silverbox mounted on grab bar) that keeps the bulbs from blowing when you rev it up. Not sure what the others are for without looking at diagram

If your new kill switch is a toggle switch it should work. If its a button that you push and hold, it must be normally open (I think) for it to work. In other words, it closes the circuit grounds the black/white wire when you push the button and kills the ignition. SOmeone will correct me if I have it backwards. As for the other wires, I think it tells you in the electrical FAQ.

For what its worth, I dynoed BB OOF vs SB OOF on my 10 mil Cub. They made the same HP, but the BB made it sooner in the rpm range, and that means more TQ. NO difference in times at the track with them, using the same tires/gearing/jetting on both. YOur results may vary.

Due to variances in the casting of the stock head, there probably is a range of accepted static compression. I just don't know why Yamaha won't specify it. I'd guess 110 to 130???

I think you found the answer. Puking coolant-leaky head gasket/oring. Sometimes it only leaks outward, sometimes it will suck coolant in. That is your problem. Coolant in the combustion chamber effectively increases compression (by displacing what would be air in the dome, making it act like a smaller cc dome.) That leads to detonation, and that is causing your problem. Like MIke said, detonation is the only thing that causes that.

Mike Z, what I meant was all of the info you posted was great info, except the part about the gasoline. I didn't mean it sarcastically. I know you just overlooked that he was running alky.

Any chance the head is letting water in that cylinder?

Same here. I have a couple of axles with hubs, and may have tailight bracket if I didn't give it away. PM if interested.

I have one laying around the shop. Make offer via pm.

Don't buy a jet kit. Get some suggestions for what jets, then you can get the individual jets from www.carbparts.com

Just noticed that you haven't jetted the carbs at all. Well, that's the problem. If they are Mikuni's I think they would have the same #s as the stockers (but not sure). If that IS the case, the mains are waaaaaaaaaaayyyyyyyyyy lean, since even bone stock is 200 mains. If the mains are that small, the pilots are probably waaaaaaaaaayyyyyyyyy small, too; and that is why it idles so high. Forget my previous suggestion and jet the carbs first. Maybe some gas carb experts will chime in. The only gas carb that I can recommend jets for is stock.

Has it ever ran right, or is this a fresh build and new carbs? Take of the filter and make sure the carbs are sync'd and make sure the slides are all the way down. If it idles that high, let the idle screws all the way out to let the slides down and try again (it shouldn't start without giving it some throttle.) Start with that; then pressure test it if it doesn't work.

Does ANYONE have dyno info out there comparing the Cascade stuffers to the regular VForce stuffers? I wonder this myself. I have the VF3s with stuffers, but now have a Chariot intake. The cCariot is round, much the same size as the Vforce stuffer, but I lost my Vforce stuffers when I put the Cascade ones in. I used to have the UPP intakes, which are much bigger (not necessarily better, due to decreased velocity.)