Oh yeah, one other quick thing - LED lights are evil on a dragstrip christmas tree. I'm used to incandescent bulbs, and try to launch once the third yellow gets to full brightness. Well, the LEDs are instantly at full brightness. That, and having a smaller front tire than before meant several redlights during the practice session. Fortunately, I got used to it, and only redlighted once during competition, and it was a race I would have lost anyway.
Video of a couple of practice runs. The guy in the other lane is running a Yamaha Vino converted to electric power. Its kind of fast.
http://youtu.be/EmaPPWVJrEY
Did a bit of interpolating based on Honda's specs for peak torque and peak horsepower (19 HP @ 7500 RPM, 15.5 lb-ft @ 5000 RPM). Assuming a linear falloff of torque from 5000 to 7500 RPM (big assumption, but I don't have a dyno), I was giving up almost 2 HP due to a max RPM of 6270 at the Spring Nationals. Did a little bit of work to the bike to pick up my max RPM on the track, I'll report back tomorrow, but I think I've managed to recover more than half that lost power.
1.1-1.3 HP may not be much on a car, but on something this small and light, this should make a significant difference. Anyone want to hazard a guess on my fastest E.T. tomorrow, based on my 10.96 last weekend?
10.45
Ended up going the other way. Best was in the 11.3 range. I don't think my changes did all that, though. Was having some issues starting the bike that I haven't had before. Will be investigating, after getting the Neon back in shape.
Was good to see some people at the race yesterday, but otherwise it was awful. Bike was running slower, and still somewhat inconsistent.
Myself and one of the other faster riders did what we could to not get paired in the first round, but as usual the gods of lane selection hate me(5 lanes, 10 scooters, we're both lined up in lane 1 and lane number 1 did not get called in the first 8 draws), and we got paired together. Anyway, he's the only one there who can pull consistent reaction times better than me, so I had to be on my game. I ended up redlighting, and even if I hadn't, the scoot was .15 seconds off from my selected ET, and I would have lost anyway. He went on to win the overall, and yesterday was one of two double points events of the season. So, I'm behind the eight ball for the rest of the season with a 90 point deficit. Even if I win every race from here on out, he'll need to get knocked out early at least once just for me to catch up.
King of the hill went similar, but not as bad. Started with 6 bikes, and made it to the second round. Did not get the bye, and lost to the bike that eventually won.
Time to concentrate on the rallycross car for the next few days, then I can get back to figuring out whats wrong with the scooter, and maybe making it a bit faster.
eastsidemav wrote: Quick pic with the Abarth:
This pic made me laugh. This forum attracts the strangest people 
Now, just bring that Zuma on down to race someday. Its not that far of a drive
Next race is in a month in Wisconsin. This weekend, I'll be tearing into the bike, and trying to find out why it was having some running issues at the last race, and I'll also do some clutch work, raising the launch RPM, and maybe putting a weaker main spring in.
The other update: I picked up a non-running chinascoot a week and a half ago, and am going to start on the next build soon. Initially it'll be a budget build, but eventually, expect big bores, nitrous oxide, and an ultralight bike 
Oh yeah, Evan, I checked, you are more than welcome to bring out a minibike for bracket racing. As a matter of fact, pretty much any safe motorcycle with an engine under 500cc is cool for running in the brackets, though I'm not sure about king of the hill.
The new project:
Someone was using it as a boozer scooter, they had strategically placed stickers over the displacement on the body panels. Known bad engine, supposedly due to overfilling the oil. I bought it cheap enough that even if all the internals are shot, it was worth it. I might get lucky, and just need some top end parts.
Drained the oil and gas tonight, and pulled the engine. Oil looks good, so the crank and crank bearings may be okay to leave as is. However, when I pulled the carb so the engine could be more easily dropped out, here's what showed up:
I didn't run a magnet over the fragments, so for now, I don't know if those are from the valves, the piston, or something else. I should get the time to pull it apart tomorrow and find out. Hope to put together a list of parts and make an order soon. Good thing parts are pretty cheap.
Cheap scoot was more thrashed than I thought, but still worth it so far. Parts are arriving for the engine build, so I'll probably assemble it later this week, so I can reclaim my workbench.
In the meantime, I pulled the side panels off the race scoot, and cleaned the connectors for the electric choke and the ignition. That appears to have fixed the issue I was having at the last race where it didn't want to stay running right after it's fired up. At some point, I should go back and try to clean as many connectors as possible.
Tonight, I pulled the clutch assembly out, changed out to stiffer clutch springs, and switched back to the stock contra spring. A quick test ride later, it feels faster. The next race is in WI, in a little under two weeks, so we'll see then.
Still enjoying this thread...
Me too. 
I should upload some pics of the cheap scoot engine carnage...
Promised carnage pics. I pulled the cylinder head, and this is what I saw:
So, yeah, a valve came apart and started bouncing around inside the combustion chamber. Here's the piston:
Metal fragments all over the inside of the engine. The bore was done for, and some of the other parts, I was afraid to re-use since there were aluminum chunks in them I couldn't get to. The parts list was growing longer. Then I started pulled off the cooling fan, and found this:
Yup, it appears someone had screwed up the woodruff key and keyway, so they welded the flywheel to the flywheel nut, and the crankshaft. I had to cut this up with an angle grinder to get it loose. Add a flywheel, crankshaft, and a little bit of hardware to the parts list. And, throw in the stator, too, since it got a bunch of metal fragments into it during the aforementioned cutting.
At this point, I ran the numbers, and I could use what I have laying around, plus do some shopping, and build a 155cc engine. Or for a couple hundred more, I could get a kit to convert it to a 180cc engine. So, I've been working on assembling the engine. Here's where I am for now:
At this point, the engine portion is assembled. Followed a bunch of tutorials online, but this is my first ground up engine build. I'm just hoping it runs, doesn't grenade immediately, and doesn't leak oil from every seam. Still need to salvage the rear gear hardware from the old engine case, and then install the variator and clutch, do a little bit of other stuff, then throw it back in the scooter, and see what happens. I doubt I will get more work done on it in the next few days, since the next race is on Sunday.
Speaking of which, this race is at the Great Lakes Dragway in Union Grove, WI. I highly encourage any GRMers in the area to come on out, and have some fun. And if you've got a scooter, bring it and enter the races.
ouch... I guess that is not some ultra secret air flow design there?
I'm wondering if the timing wasn't wacked out by the new "kustom keyway", resulting in meltdown and demolition. It's hard to hear those little guys pinging sometimes... by the time you hear it, it's too late. Many moons ago, when I would hear "it lost power" at the shop, I'd cringe. Nobody wants to show that to the customer.
Looks good now, though.
In reply to noddaz:
Well, it does improve the exhaust flow considerably, which might work well with the extra crankcase ventilation provided by the hole in the piston
In reply to Beagle:
It amazes me the abuse these things can take, but this one went a little too far. I am inclined to believe the "overfilled with oil" story a bit, since the exhaust valve is on the bottom, it wouldn't surprise me if the oil was slowing down the valve closure. That is assuming its an interference engine, so it could have been something else, too. Since it was likely being used as a DUI bike, nothing would surprise me.
Managed to make only one practice run this weekend, the bike was running extremely lean. Covered up a bunch of the air filter to richen it up a bit, but ran into other issues. Packed up and left early, since it was an 8.5 hour drive home, not including stops, and we'd already been on the road all weekend.
Got to set the bike aside, and fiddle with the rallycross car, since there's an event next weekend, and we have not run a single one yet this year. Hoping the scooter's engine isn't damaged.
Time to update in the week before the next race:
The drag scooter is back up and running well. I am not 100% certain, but I think the lean condition may have been due to the carb being a little loose, and letting air in at the intake manifold. I pulled the mainfold, and it seems fine, no cracks, but the O-ring where it attached to the head was flat enough, I didn't want to put it back on. Replaced it with a new one I had in my parts stash, and it took a bit of force (and WD40) to get the carb all the way on, but it seems much more secure than before. I also checked and made sure there were no clogged jets in the carb.
So, potential lean condition taken care of, the scoot still wouldn't start. Which was my second problem in Wisconsin. On a hunch, I disconnected the ground wire on my tethered kill switch, and the bike fired up and ran fine. Looks like the rubber on the tether is getting out of shape, and not pressing the kill switch in enough. I cut up a small piece of plastic, and put it in there to make the switch work with the tether in place. It works, but I really hope I don't need to use it, because that plastic will go flying, and my race day will be over. A better kill switch is in the plans for the future.
On the the GY6 scooter - the engine is installed, but lines/wiring still need to be hooked up, and a little prep work needs to be done. Once I get the engine tuned, this scooter will get scrapped, and I'll start building something lighter
Finally, over the weekend, I picked up a 70cc 2 stroke race scooter that was part of an earlier deal. Its very slow off the line, but once it hits 4000 RPM or so, its pretty zippy. This is going to be the loaner scooter, to try and draw some more people in who are interested, but don't want to spend the money on buying a bike before they get a chance to try it out. If I can do so cheaply, I'll try to rig the clutch so it doesn't grab until a lot higher RPM, then adjust the idle up so its faster off the line.
The boozer scooter lives again! Finished hooking everything up, and after a few minor issues, got the thing started. Took it for a quick spin around the neighborhood, but didn't go far, it really needs to be rejetted. Stumbles like crazy if you give it more than a little throttle under load. Probably won't do too much tuning with it this way, though, since its getting a bigger carb and intake, and I'm going to build a custom exhaust.
I modified the front fender a bit so it'd be easier to install and remove the front wheel:
So nice when you can do bodywork with a pair of vice grips.
At this point, it'll hibernate in the garage overnight, and tomorrow after work, I'll check and see if its got any oil leaks that will need to be dealt with. I really hope not, would prefer not to have to disassemble the engine.
A couple of quick updates:
The race scooter may still be a bit lean, but probably not dangerously so. I am having a heck of a time finding a 118 main jet that fits the carb. If time permits, I may try out the 120 jet again, although last time I ran with it it was way too rich.
The boozer scooter has a minor leak, but it appears to be at a crankcase drain plug, so it probably just needs a new aluminum or copper washer. Won't worry about changing that until I drain the oil, which will probably happen soonish, since its a fresh build. Still haven't decided if I'm going to try tuning it a bit more before the bike is scrapped, and the engine goes on a custom frame.
Manages to get a 118 jet that would fit the race bike, installed it, and it seemed to be running a lot smoother. At the race on Sunday, I pulled some practice runs in the 11.7 range, so its slower, but it sounds a lot healthier. I'm also back to having a max RPM of around 6500-6600. Looks like it might be time to order some lighter rollers, and hope they are still okay aginst the stock clutch spring.
However, once I rolled the bike out for the first elimination round, I was informed my rear tire was going flat. Aired it back up real quick, but got the bye, so I didn't have to race anyone to make it to the second round. Went to air it up again, and this time the air was escaping almost as fast as I could fill it. Inspected the tire for any punctures, and it was fine. The valve stem failed.
This season is getting very frustrating.
Neat build! Any turbos or fuel injection dreams?
In reply to RossD:
I've considered fuel injection at some point, probably using microsquirt. Biggest problem is where to get a small enough throttle body/intake combo. The CBR 250 uses drive-by-wire. Not sure how the foreign market Ninja 250 was set up, but thats a possibility, if its a single tb + cable throttle.
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