Low Observability Motorized Bicycle

[Member 5549]

Low Observability That's Stealth technology at it's finest.
Just cover that bike with some R.A.M. ( radar absorbing material )
And It will be stealth and the radar gun will say your going 2MPH when your going 25mph

 

[SirJakesus]

Rack mount friction drives are the best way to go for a stealth bike. Everything about the bike will look like a normal bicycle, even the rack. Just deck the rack out with panniers and a rigid bag up top and cover the engine with a loose woven cloth and you're done. You can lift the engine when you want to pedal and engage it when you want some power. If you're traveling bicycle speeds and pedaling nobody will EVER suspect you have an engine on it unless you ride right past them and they can hear it. I know Dimension edge even has an engagement lever so you don't have to stop to drop the roller onto the tire.
I've thought about going this route with my MB's but I happen to enjoy the trouble of wiring up my own electrical system and being recognized as a motor vehicle. The ability to travel 30mph without worries about the po also helps. Plus, I get more experience and skills in case anybody wants to buy one from me. I'm a big fan of the old style mopeds with pedals but all they sell is those lame scooters nowadays.

 

[KilroyCD]

I live in PA as well, and have been frustrated in my attempts to get my builds licensed for the street. PennDot states that anything under 50cc need not be titled, yet two pages later in the same literature packet they state that for anything to be registered it must be titled. I will be working with some PA legislators (now that the elections are over) to try to get the motorized bicycle category defined and MB-friendly laws to be enacted. What I'll be proposing to the lawmakers is not a formal registration (with title), but a "road permit", much like the bicycle licenses of yesteryear. It could be in the form of a plate, or of an official, state issued adhesive sticker (along the lines of the inspection sticker that adorns my Whizzer). Wish me luck, guys!

 

[buck]

We need the Pennsylvania Motor Vehicle Code to be specific that
under 50cc is to be considered as a bicycle. No more conflicting
sections of the code. No stickers, plates, or paperwork needed.
Just gas up and go. Other states have it that way and it works
for them. Why not the Keystone state? I have over 600 miles
on my bike this summer. No problems... But i ride it no faster than
a bicycle. I go slow thru residential neighborhoods and wave at
everybody that i see. Yes quiet and stealth is the way to go.
I also ghost pedal when i see somebody looking. I have found one
common thing with everybody that flags me down when i am riding -
They all want one of their own!!!

 

[machiasmort]

I recently felt like I won tour de france or something on the Buffalo bike path. People linning up to wave. Says something about the law in the state where you live when people go through that much trouble to show support!

Blue Collar Bob put up an excellent post on quieting Ht's down. Search his name for posts and I'm sure you'll find it.

I packed my pipe loosely with steel wool (in addition to bob's advice) and turn my idle down real low after the bike is warm. Maximum stealth mode!!! Very quiet until you hammer on it!

 

[loquin]

I would think that some sound deadening material (sound deadening sheets, or, egg-crate/pyramid acoustic foam) lining the enclosure would also help. The same sorts of things that are used in sound studios or auto installations...

ref Parts-Express

 

[AlphaGeek]

A couple of things to keep in mind regarding use of sound-absorption materials:

(1) With small motors in general, and two-strokes in particular, an awful lot of motor noise actually comes from the intake. Dampening the sound waves emanating from the intake should be a high priority for any would-be stealth motored biker.

(2) Practical sound suppression in an open space (as opposed to an enclosed room or container) is the enemy of free airflow. Any sound absorption approach for a small gas motor will have to balance sound suppression against adequate airflow to avoid overheating the motor.

(3) The lower the frequency, the more omnidirectional the sound and the harder it is to suppress. Getting the high-frequency stuff under control is easier by a very wide margin, so focus on that first.

For example, since upgrading to a low-restriction K&N-style filter, I've noticed a significant increase in noise on my Tanaka 33cc. After I get the carb and exhaust upgrades fully sorted out, I will be looking at ways to redirect and absorb this noise. Ideas include a 'dome' or 'can' over the filter assembly (but not blocking/touching the actual filter element) lined with rubber sheet and fiberglass.

-AG

 

[KilroyCD]

We need the Pennsylvania Motor Vehicle Code to be specific that
under 50cc is to be considered as a bicycle. No more conflicting
sections of the code. No stickers, plates, or paperwork needed...

That is the way I'd really like to go, but I'm a realist. As more of these bikes find their way into mainstream use, PennDot is going to look for a way to regulate them. If we begin at a common sense starting point, it might be easier to get MB-friendly legislation enacted. When MBs start showing up on the roads in increasing numbers, it is inevitable that some politicos will try to find a way to turn it into revenue for the state. It could end up being costly for us MB riders, so to try to get a low cost common sense scheme in place now is likely to be to our advantage.

 

[whodathunkit]

Good points, all, about fixing the legislation to be more friendly to us. However, the issue of annoyingly loud sound is still an issue that could get the populace up in arms and cause new problems for us.

I keep thinking about my back-pack 2-cycle leaf blower. It's actually pretty quiet, even when screaming. Two of the things it has going for it is are a complete plastic motor enclousue, and not being hard-mounted to a big steel frame that transmits high-frequency mechanical vibrations. I think this helps with a lot of the mechanically emanating noise. In a frame-mount installation, I think this translates to a shock-absorbing mount, a decent muffler, and a sound-deadening enclosure.

Anyone done any of this?

 

[loquin]

The sound deadening sheets I was talking about are about a quarter-inch thick, and are self adhesive. You can buy them to cut road noise by placing them on the inside of the doors on your car. In a car, they will cut external noise by about 3 db, which is by 50% They actually absorb sound by converting the molecular motion of sound into heat. If you had a box with an open bottom, lined with this stuff on all the remaining sides, you should get noticeably fewer dBs being released into the wild...