52cc Stage 2 CAG CVT powered X-Games Motobike

So after looking around a lot, getting frustrated, then sleeping on it. I've found a better motor that will fit that makes 5.3 hp at lower rpms, and a rock crawler gearbox with steel gears that has a 3:1 reduction. That would be good enough on its own with a 10:1 final drive for a 30:1 total, and a 60mph top speed with the motor capable of pushing a bike that fast.

It looks like rc motors are amp hogs, so big AGM's is still the way to go battery-wise, unless I want to spend $800 on batteries.

This thread might end, and the engine and CVT get reserved for a BMX. I had a great idea for a four stroke bike last night that would be a fun and easy build, and could be my street machine. Around here all the bike trails say no motor vehicles, and I'll get into trouble no doubt if I rode a gas bike offroad.

Sadly, I might have to end this build here as a gas bike and link to the electric build start. This bike will work GREAT for a gas build, it just won't be as useful as I'd like locally, so that's why the change of plans.

Well I just ordered some stuff to modify my mx1000 because I've gome to a realization that it's built like a tank and can handle the weight of batteries. The frame actually looks to be stronger than the regular pit 50 designs since it has lots of bars to hold the batteries.

So...

The Motobike project will continue with the Cag unless I end up selling the Razor, in which case I'll be in need of an electric bike. I guess a mild hybrid would still work, but the cost and weight of a lot of high capacity batteries won't work well with this bike. I chose to get new batts for the Razor and some other stuff because the Motobike will never be as tough, which is important off road. The suspension on the Razor works well too. The Motobike front fork will never be that great, or as good as the MX anyways, and the rear shock could use the same treatment as the MX with a 10.5" air shock, although without a longer front fork, the rear shouldn't be done.

I'm going to do the Cag first, if there is room in the bike and my budget I might try the hybrid, but the power and range added needs to make up for the weight. It's hard to tell without making some physics problems to get an idea of the relative setups' performance.

Going electric I would have an excuse for no pedals, and an alternative lazy mode of limping home, so I'll keep it in mind. I just think a 3-5 hp electric motor will drain 5 ah batteries in a matter of minutes, so Lithium seems like a necessity if the additional crap is to be worth it. Make that a 48V pack and the price doubles from a 36 because they're less common.

This fairing is most likely going on the Motobike, along with clip-on handlebars, because the 1" triple tree risers will work perfectly with some for a pocket bike. Since this bike is of unknown toughness, maybe submitting it to the rigors of offroad and motorization is a bit much, so it will be a street bike now. Slicks, farings, and minimal suspension travel will be the theme. The forks and shock will remain stock, although I might put a dab of really sticky grease in the sliding parts to try and get some damping out of them.

It's going on as originally planned with the Cag engine, and then maybe later I'll Hybrid this bike. It's settled, I gotta stop making my projects parts-bin moving targets, because I have boxes full of stuff that's brand new to go on this bike as a gasser, not a good idea to waste.

It will make a good road bike, as I think it will be able to hold up to the motor on pavement guaranteed, it has a cross tube missing on crf50's that do fine. The thickness of the aluminum frame is a concern, but I plan on feeding the forces through the stock holes and welding bungs in if I need a new mounting spot. Holes without reinforcement cause frames to crack in half.

I might as well make this my racing bike, because it fits in my car easily, and it is lightweight, something my OCC bobber will never be. I want to drive to so-cal for the races if I can, and not having to buy a van for the trip would be great. This bike with just gas alone might be light enough to go on the trunk bike rack, so I could take my e-tard with me too in the back seat!

I woke up early and couldn't get back to sleep so I drew this in paint. The bike will be black but this shows the details more clearly.



It's going to be uncomfortable with clip-ons, but it will have the right stance for knee draggng so whatever. This is a racing bike!

Buzz Buzz Buzz, ya know what I mean ;D

Picked out some clip-ons. I'll use some of that Metalcast paint to make the triple trees match. The top of the existing steering tube is coming off and the clip-ons will clamp to the triples at the tops.

No pedals if I use the CVT, I can have pedals if I use a geared hub. It's hard to decide which to use. I could save the CVT for later, prolly shouldn't use both because the drivetrain losses would be big.

I was thinking it would be nice to go to mag wheels if I can afford it, although the geared hub would have to be jackshafted to do that.

Part of me wants pedals, with the CVT they won't be necessary because starts will be a smooth takeoff. The geared hub will probably be the same story, just not as smooth. Gears can be problematic, but they're fun and reliable enough on the street. I might save the CVT for a HuaSheng build later.

You see, the problem is the endless possibilities. It's crazy.

The fairing came in today, along with the rest of the parts. The fairing is scratched up from shelf wear so it will be painted black to match the bike. It's a shame since the Honda paint job is cool. It's not a Honda, so black it is. It will fit like in the bitmap rendering, stretching back to the bottom bracket and will have plenty of room for the motor.



I really don't know about having pedals AND clip on handlebars. I don't think it would be comfortable trying to pedal this especially with the full fairing that's actually a foot wide. This will be more of a moto-cycle than a motorized bicycle, but if I can incorporate an electric motor, the hybrid thing should be enough to cover all the bases legally for street use. I'm thinking a 36v NiMH is the way to go for the electric, I found one for $100 with 5ah and it weighs only 5 lbs. I could mount one for the technicality, and then another later for range improvement on electric. I would like two small batts, because they can fit attached to the metal brackets for the fairings that are wicked stiff.

This is going to be awesome! Can't decide between mags or spoked wheels. If I use the hub in a wheel I'll get a wide rim for the back. CVT opens up options for mags or moped wheels. The wheels on the bike are perfectly fine, although they're kinda narrow. It seems like tire stretch is good for street slicks on bikes, so I might get a wheelset and put a Sturmey in it. Mags are heavy too, especially if I use moped ones. The moped ones are rated for high speed, but the hub centers have drum brakes I don't want as well. You can put disc studs through the backside, but I think the weight will be prohibitive on this one.

Well I'm going to have a moped plate as required in CA. The local Sherriff's Dept. harrass me on a regular basis on the legality of my cars, so I don't want to deal with their tickets for an unregistered motorcycle.

With the electric motor it should be A-OK, since mopeds in SF don't have pedals usually, they're all running racing engines nowadays.

I noticed when I put the Cagillari bodywork on my Raven OCC bobber, I picked up about 3-4 mph top speed and could sit upright at 30 comfortably. I'm a little worried about cooling, and not melting the fairing since it's thermoplastic. It is huge however, and should clear the hot bits by a couple inches, and I'll put aluminum tape plus an air gap aluminum sheet heat shield under and around the motor so the bottom of the fairing doesn't shrivel.

I might be able to fit it without cutting the wheel hole if I install it raked down, which will have the added benefit of a more vertical windscreen, because they make a low pressure bubble.

I think as long as your pedals are there they can't do anything to you. I'm thinking about making another build that's something more like a YSR with pedals as the ultimate stretch of the "moped" definition in CA, to have something that's more like a scooter, yet still has $18 life reg and pedal backup. It shouldn't matter what the style of the bike is, if it meets the technical requirements.

However, I wouldn't put this fairing on my electric motard because it would create unnecessary attention and I'd have to explain it's an electric bicycle, not a "pocket bike" which are strictly forbidden. It's got crf50 sized tires and looks like a motorcycle, on a bicycle it would be less of a hassle I bet.

I know I'll keep on being harrassed, because it's in their nature, but as long as there is pedals or electric drive you should have no legal issues.

Thinking today about how the new rapid shifter derailleurs are trouble free, and how nice it would be to have nine speeds, an obvious solution comes to mind.

I was going to lace a Sturmey S3X that I have into 1.75 rim, actually, pay somebody to do it, because I hate building wheels

Instead, I might just use a cassette wheel and try a rear derailleur. Seems like a more trustworthy setup. I can save the S3X for a jackshaft for something else.

The S3X doesn't have disc brake holes either, so using a laced up wheel would mean I'd have to make a brake mount or go without, not cool.

I've got something in mind that will work with a Shimano Deore rear derailleur, cassette, and rapid shifter. From what it sounds like and my experience on my mountain bike, the Deore is a good derailleur.

I would prefer to find a derailleur that has rapid descent, so it upshifts under spring power instead of downshifts. Maybe it's better the other way around though because you can feel the derailleur through the button, when it's done shifting.

Just babbling thoughts.

I'm thinking cutting it at the line and putting in aluminum sections alongside the engine would be a smart way to stretch out the fairing. That way it won't melt

The handlebars come right out with the triple trees intact. This bike is made for stuff like this! I'll put the gauges on the old steering clamp mount, although that tube can be removed completely.

It's a good thing I'm not putting this stuff on credit!



Bought a magnesium wheel set. I want a derailleur and this is the only mag wheel I know of with a cassette freewheel.

I considered moped wheels, they're kinda heavy, have drums which I don't need on this bike, and can't use a derailleur.

The popular BMX mags that are cheaper are actually made out of plastic with carbon molded in. They dent easily.

Supposedly these Teny wheels, while somewhat heavy, they boast about their strength. They advertise with a guy jumping his mountain bike off a staircase. I just want wheels that will stay round at high speed so hopefully these are as good as everybody says. I don't want to deal with spokes and truing, and will prolly use my Sturmey S3X on my Thruster Fixie for pedaling or as a moto jackshaft later on.

I'm pretty psyched about these wheels. I plan on running moped 2.5-16 tires tubeless, which they say is okay. If the rims aren't cleared I will do that because Mag gets crusty quick. They will look great with the disc brakes attached! I'm more excited about this build than my Raven bobber with the KTM clone. I think this bike will be just as fast or faster with half the power.



I also bought a 415 sprocket for a Z50 bike that hopefully will fit my CVT splines, so I can run the output to 9 speed chain to the derailleur.

Any input on excellent derailleurs in the $50 range welcome, and cassettes with quality sprockets that don't wear down under shift kit power.

Thank you SoSauty for helping me out with some batteries! I think I'll try using them as a range extender to my MX1250 until I get the water cooled brushless installed on the Motobike.

I figure if I want to continue building motorized bicycles, I have to be able to resell them. That's why I've taken the no holds barred approach to building my Raven OCC, the MX1250, and now this. I want to make a name for myself as making properly engineered high speed racing bicycles, so I gotta put all cards on the table to be able to design around all the components at once. I only wish it wasn't so expensive, lol!

http://motorbicycling.com/showthread.php?t=42405
Here's the raven thread. This is the bike that got me into motorizing. I bought it already set up used off a guy, supposedly I'm the third owner. I need to finish the clone build. I've been at school so not at the race track to weld it up.

I found cool louvered aluminum sheets that might be a good way of extending the fairing.

Trying to figure out the right derailleur and cassette, I think SRAM X9 is the way to go from the review, they click loud and don't bounce, both important things on a motorized bike. The trigger shifter is thumb activated so you don't have to release the grip.

I dunno yet, Cagabusa readily comes to mind, but that's too easy and it's been used for multi-engine Cagllari drag builds.

I'm sure I'll have a name for it after I ride it for the first time, hope its a positive one

I think I'll run the moped tires tubeless to save weight, since I have a gallon of off-road Slime with the big chunks that even clog the bottle pump. Sounds like I'll be faster and have more grip tubeless and the wheels are approved for it. This is all contingent on the moped bead seating on bicycle wheels deep enough, which I'm gonna have to see.