Going racing on the cheap. $500 racers, based off of motored bicycles.

[scotto-]

I'm certainly not gonna hold my breath till this fantasy comes about........ya talk about variables for people to disagree on........and no pedals?

Why not stick to racing cheap, used mopeds?

Yup, on the rear pegs. There will be no pedals.

Clever, but that price is steep enough to keep participants out of the game. And more importantly, you lose "your" saddle, and bars, and brake setup.



The sidesaddle mount gets around the frame problem. The motor doesn't "fit" the frame anyway, so by having a standard mount method, that will work on ~any~ frame, lets you do things like swap engines quickly.

The only problem that a rider might run into is brake mounts. In the case of the SIMS Torch I bought, the brakes are limiting how far forward I can mount the engine. *shrugs* it's not a big deal.

I should have the engine mount done this weekend, so you can see what i'm talking about.



I would. Most of my friends would. Sure, it'll look weird without a fairing, but once the fairing is on, you can't see that it's mounted to the side.

I'll let you in on a secret too. Bicycles are lopsided! Gokarts too are almost universally lopsided.

Importantly, the motors CG is only 2-3 inches away from the center-line of the bike. And the bike is 20-30lbs as is. So the total CG offset is only an inch or so. When balancing the bike, it was hard to tell it had any lean at all. Of course, if someone shows up with a 12lb BMX bike, that offset is going to be a bit greater.

Wait an see. Wait.. and see me dragging fairing in a parking lot.

 

[d_gizzle]

You got a link to that blog?

 

[nerobro]

You got a link to that blog?

http://realtinker.blogspot.com/

I can do the Team America secret signal no handed while riding my chopper, lol. That has to do with the gyroscopic stability of the wheels at speed.

The interaction between rake and trail actually...

I'm adding my input to this thread because I think it would be sad to see another spec class built off of compromised machinery. *snip*

X1/X2 Pocket bike/aka 52cc auger engines hooked to a 33:1 box will have enough torque to start from a stop even geared for 30 mph

Show me the engines. I'm interested. Though I would miss having the manual clutch.

And we talking bmx. No shifters in bmx that I've heard of. Bmx is single speed. And with no pedals,how do you start off the line? Top of the ramp start? The engine you have in that picture isn't designed to be started from a dead stop. I'm not willing to ruin clutches to race a bike I can not ride on the streets. Practice at the track only?

I was using other examples of bikes that have offset CGs. They relate.

The only problem I'm aware of with the motored bike engine is that the clutch might not be up to standing starts. There are solutions to that.

It's a race bike. For racing. At 66cc and more than a 20mph top speed, it's not legal for use on the street. Yes, you'd have to practice in parking lots, or at the track. If you want a bike for use on the street, look elsewhere. This project isn't that.

I'm certainly not gonna hold my breath till this fantasy comes about........ya talk about variables for people to disagree on........and no pedals?

Why not stick to racing cheap, used mopeds?

I don't think i've spoken about variables for people to disagree on.

It doesn't work. The differences between mopeds are to great, and it becomes imposable to police. Racing mopeds is a dollars game. Buying them is hard. And what quickly happens, is you need to buy THE RIGHT moped. And they don't look the part.

 

[MotorBicycleRacing]

It's a race bike. For racing.

At 66cc and more than a 20mph top speed, it's not legal for use on the street.

Yes, you'd have to practice in parking lots, or at the track. If you want a bike for use on the street, look elsewhere.

Hey, an interesting concept you posted while I was on "vacation" on the other side.

What are the State motorized bicycle laws in Chicago IL?

Actually the 66 cc China Girls and 30 mph are legal in California and
no one cares if you go a little faster or have more than the 2 HP limit.

The only thing illegal about your BMX racer would be that is doesn't
have functioning pedals.

So you can ride your race bike on the street and even better your ride
to the store China Girl on the race track in the new Amateur Class.

How are you going to get these bikes off the starting line with no pedals?
Going to be a slow start, are the racers going to duck walk them?

Run along side then jump on like a Le Mans start?

I'm ~ 6' 2" tall (178 lbs) that's mainly my long legs so I don't fit on little
BMX bikes. I did a few laps on Arrow's 16" wheeled tiny Junior Stingray
and dumped it in an easy corner at the April race so I am staying away
from midget bikes.........

 

[16v4nrbrgr]

Have fun with that nerobra, lol you have an answer for everything so I guess now all that's left to do is actually do something.

 

[MotorBicycleRacing]

Have fun with that nerobra, lol you have an answer for everything so I guess now all that's left to do is actually do something.

You can talk about actually doing something. LOL
You are starting to resemble Safe.
Lot's of forum posts, rules but nothing in real life.

Never even come to a race......

At the very least put on a (GTG) ride, meet up in Norcal and see who shows up?

That's how SoCal Motor Bicycle Racing started and despite what you
may read here in a couple of threads we are taking off this year.

 

[nerobro]

Hey, an interesting concept you posted while I was on "vacation" on the other side.

What are the State motorized bicycle laws in Chicago IL?

In illinois, you can go two ways. "moped/scooter" or "motor assisted bicycle". A moped or scooter, is limited to less than 30mph in 1 mile, and less than 50ccs. All mopeds and scooters in Illinois must be licensed. (at the exact same cost as a full motorcycle)

A motor assisted bicycle can be gas, or electric. But can't exceed 20mph. And quite literally no officer in Illinois knows the laws on them, and will harass you at any given opportunity. Ask me how I know ;-)

How are you going to get these bikes off the starting line with no pedals?
Going to be a slow start.

Run along side then jump on like a Le Mans start?

That's exactly what they did in GP racing right up until.. 98 or 99? Something like that. Once they started considering 4 strokes they stopped push starting them.

I'm ~ 6' 2" tall (178 lbs) that's mainly my long legs so I don't fit on little
BMX bikes. I did a few laps on Arrow's 16" wheeled tiny Junior Stingray
and dumped it in an easy corner at the April race so I am staying away
from midget bikes.........

The bike shouldn't be midget at all. The saddle will be low and far back. I'll have a saddle built tonight and hopefully motor mounts too. My "test dummy" is 6'2, so this should be the right size for people like you. I'm 8" shorter than that, and the 19" bmx frame I've got has me stretched out pretty far. Yey for garage time though!

*Sarcastic crap*

Yes, I have answers for most things. But I also know I don't know everything, that's why I asked you about those motors. But if that's the way you wanna go, leave, you're not helping.

To alleviate any doubt that "I do do things"

This was my motored bike.

 

[nerobro]

A bicycle I built from parts:

And a mill I built from scratch:

Which I used to make parts for the motored bicycle...

And now.. I goto my garage.

 

[d_gizzle]

Maybe I should have said cruiser frames. Cuz your motorized bicycle is the style frame I'm talking about. When its the 20" wheel version its called a lowrider frame.

 

[nerobro]

Well, that engine isn't going to work. After installing the sprocket, and checking stay clearances, this is a non-starter.

Okey, now my idea for an engine is toast. Where do I find a X wahtever engine, to try for this formula.

 

[16v4nrbrgr]

You can talk about actually doing something. LOL
You are starting to resemble Safe.
Lot's of forum posts, rules but nothing in real life.

Never even come to a race......

At the very least put on a (GTG) ride, meet up in Norcal and see who shows up?

That's how SoCal Motor Bicycle Racing started and despite what you
may read here in a couple of threads we are taking off this year.

Hi Neil,

In case you haven't noticed I've been developing an 8hp electric motard (documented here), also a 9 Hp Morini Clone OCC chopper (also documented here, the Raven) which I have been riding since last year, (thousands of miles). I'm also developing a cvt + 9 gear street bike and also a BMX with a small equipment Predator motor. Ahh, yeah I'm not doing anything because I INTRODUCE ALTERNATIVES to the ubiquitous half broken Happy Time.

Just because I can't afford to go play with you this month, and because last race weekend I was running Pro Formula Mazdas at Laguna Seca (better than playing with toy bikes in my opinion), you have decided to go to war against me and you think that being inconsiderate to me in forum posts and saying I don't do anything, and saying I'm like that Safety tool that put up bar graphs and pie charts, well that DOESN'T ENTICE ME TO ATTEND AN EVENT YOU ARE RUNNING.

You don't understand that, people will come if they want, making me angry at you is not a way to make me want to go hang out with you in the hot sun out in the middle of nowhere all day, lol. Marin is absolutely gorgeous all year long! I'd like to have a GTG ride, but nobody is interested, I might have a new friend to ride with locallly, but I don't see this type of thing taking off around here, because there aren't many people that know how to fill a tire up here, forget building bikes, lol.

What this thread started as was throwing around the idea for a parking lot racer BMX with farings and you have maneaged to go out of your way to call me out and say I'm not doing anything because I don't go "race" with you guys.

Calm yourself, I really don't feel like going now if this is what you're like in real life.

 

[dmb]

believe me when i say people go to the races to have fun. not because of neil, most just put up with him. he rub's some people the wrong way and he just does not know it. he is what he is. i've been to most of the races, his and baird's and its the racers them self's that make a good time for all. that said, he does a good job putting on his race and for now he is the only show in town. dennis

 

[MotorBicycleRacing]

Well, that engine isn't going to work. After installing the sprocket, and checking stay clearances, this is a non-starter.

Okey, now my idea for an engine is toast. Where do I find a X wahtever engine, to try for this formula.

Reed valved Arrow motor on a Junior Stingray.

Junior Stingray's size in comparison to a 26" wheeled Arrow racer.

 

[mat_man]

You can build a friction drive cheap and fast if you are handy and can scrounge.
Easy fit on a 20" BMX, front or back tire.
Plenty of how-to videos on Youtube.

Use a stock motor from chainsaw, weedeater, or blower under ??cc.

This would be close to the French Solex moped used in the popular Rock'n Solex race:

 

[nerobro]

So, I'm looking at something with a centrifugal clutch.

Any suggestions?

 

[magrider]

harbor freight 79cc 4 stroke $100

 

[scotto-]

harbor freight 79cc 4 stroke $100

Yes, what Magrider said! A great little powerplant for a cheap price, I just bought another one

 

[nerobro]

It's not exactly little. And it's quite wide. I don't think it would work in this case. :-/ I"ll go take measurements this evening. But it doesn't look good.

 

[scotto-]

It's not exactly little. And it's quite wide. I don't think it would work in this case. :-/ I"ll go take measurements this evening. But it doesn't look good.

It is little, a little wide and it looks great!

 

[mat_man]

This should work with a 20" mountain bike:

the scooter guy brand motorized mountain bike
https://www.youtube.com/watch?v=ngYL6nRBaKw

3 or 4 usable gears.

 

[mat_man]

So, I'm looking at something with a centrifugal clutch.

Any suggestions?

This Friction Drive has a centrifugal clutch, kit will add about $200.
40cc Robin Powered Bicycle
http://www.youtube.com/watch?v=G_J9Yzoux4M

I would do this:
Homemade hand clutch, scissor lift for Friction Drive.
http://motorbicycling.com/showthread.php?t=31318
But use a chainsaw motor 40cc to 65cc.

Friction Drive Shuttle Buddy 25cc 2 strokes matched the 50cc 4 strokes at Grange.


The French watercooled, reed valved, 50cc Friction Drives claim to do up to 70 mph: