Top Speed

grinningremlin said:

My main ride is a LWB recumbent, doesn't even come into it's own until about 15mph, seems to ride smoother the faster I go.I figure my top with a 40cc is 38-39mph on a flat, my concern is standard bike brakes aren't made for the speeds I can reach so I keep is down.

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Is not it a great feeling to go 40 mph on a bicycle , but the biggest problem with high top speed on a bicycle, I think, is rims and wheel bearings (most of bikes have not good wheels), the brakes does not feel as a big problem for my own safety

I've got Worksman wheels on both my bikes. Hot Dog Carts use similar wheels, they are very beefy, and give a nice gyroscopic feel at speed. Kevlar tires, and thornproof tubes round out the package. Top that off with a clamshell hub / sprocket and you've got wheels you can trust.

35 MPH is my max "cruising" speed...

...although I've pushed it to 40 MPH a couple times just to say I did!

In everyday riding, I usually stick to about 25 MPH. Above that, the bike feels stable, but the overall experience just seems too frantic for a bicycle.

Huasheng 142F 4-stroke, Q-Matic drive, aluminum-frame Giant cruiser.

My 66cc Zoom engine stock, tops at 49.5k, 30mph, but my average speed is 28k. The engine guide states the engine should do 40k.

my 49cc china girl has topped out at 59kmh so far with an SPB shift kit and a custom Jaguar style expansion chamber, still lots of mods to do though, new carb/ignition and some gearing adjustments are needed, i want to be able to do a reliable 60kmh (not constantly pinning it on a flat road)

Max-M said:

...although I've pushed it to 40 MPH a couple times just to say I did!

In everyday riding, I usually stick to about 25 MPH. Above that, the bike feels stable, but the overall experience just seems too frantic for a bicycle.

Huasheng 142F 4-stroke, Q-Matic drive, aluminum-frame Giant cruiser.


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BA HA HA HA, frantic is a good word for the feeling.When you're on a flat, hit a small bump and realize BOTH tires have left the pavement you're going too fast.
AL frame, check the welds every so often.

I broke my land speed record the other day on my 66. hit a whopping 32 mph according to the car speedometer next to me, or 35 mph according to the speedometer on my bike.

What kind of rpm are you guys with shift kits seeing at 25 mph? I run out of room to rev at 30 if I don't have any downhill assistance and my ass is too fat to put a smaller gear in the back.

butre said:

What kind of rpm are you guys with shift kits seeing at 25 mph?

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I cannot comment on the 25 mph speed (in the real world) because the law in my location says that a motorized bicycle cannot travel any faster than 12.42 mph, and i naturally comply with the law to the very last letter, being that whatever gear i'm in, the bike travels no faster than 12,42 mph, even if i hoist the bike to 2,000 feet and throw it out of a Cessna 172, the bike speedo still shows 12.42 mph; being totally compliant with the department of motor vehicle regulations.

I am glad that's been cleared up. Now the DMV spooks on here can sleep peacefully; knowing that 12.42 mph is going to save all of the whales and the pandas and some endangered spotted arsed marsupial residing in a god forsaken place.

If, and i say "if", my bike (in a parallel universe; untouched by the insanity of DMV regulations) could hypothetically travel at 25 mph with the installed low range jackshaft sprocket sizes of 9T - 48T; powering a final drive 38T chainring sprocket to an 11T cassette sprocket, the engine rpm at 25 mph would be 3,400 and 4,700 rpm @ 31 mph.

Naturally this top gear ratio is only for static display purposes, because the DMV official running beside me when i'm riding my bike, always ensures that the bike never travels faster than 12.42 mph.

I broke my old land speed record today after new gearing and a clutch rebuild, I'm able to hit 41 mph. My bike is very comfortable up to 30 miles per hour and only a little wild at 35, but at 40 everything feels very urgent. I'm going to need some front suspension to take it any faster. I'm amazed at how comfortable a ride it is with the suspension only in the seat. It's no wide glide but I'd rather take this thing on an expedition than some of the sport bikes I've ridden.


I need to find some stickier tires, I run out of grip long before I run out of cojones and that's almost had me on my ass twice today. It was dry as a bone out today too, I'd be killed if I rode like I did today in the rain.

butre said:

I'm able to hit 41 mph.

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going down a steep hill?