Mechanical sustainability with large engines?

[HoughMade]

I am running a Honda GXH50. Once it was all set up, ran like a champ. I blew it apart for paint, but road it a lot looking kind of rat rod (see sig pic).

The Honda engine is much smoother than the Chinese 2 strokes, a lot less vibration, and many with those engines have put thousands of miles on.

That being said, these contraptions do require more frequent maintenance than a non-motorized bike or a scooter. If gas and go is what you want- forget this. This is for people who don't mind lavishing some care on their mounts, or, like me, absolutely love wrenching. You can't use cheap parts or be haphazard and expect anything to stay together. For instance, I put high quality, heavy duty wheels on (11 ga spokes), but even knowing the wheel supplier is a quality operation (Husky), I repacked the wheel bearings myself for certitude. The same goes for the bearing on the fork/headset bearings and the crank bearings. You get the idea.

I have no idea why a fork or frame with a larger 4 stroke would wear down. What you will see is more frequent wheel bearing and brake maintenance. No big deal. The original motorcycles were bicycles with engines (pre-WWI). Even then, some were running in excess of 1000ccs (yes, I said one-thousand).

 

[Mountainman]

There it is from HoughMade ----- 1,000cc MBs -- those were VERY COOL !

it's all in understanding the limits of our equipment

I would love to have a MB (bicycle) with all kinds of hp
knowing what we are working with - much
being gentle when we have to - can rip with a slight touch
I have been thinking about a true beast of a MB a lot lately

I know that I could keep this beast up and running - much respect
but - I will also guarantee you
my son - would tear this thing apart - in no time !!!!

At many times - it's all do to - the rider..

While repairing equipment for the City -- saw this a lot
poor operators = torn up machinery...

Happy Riding from - Mountainman

 

[Drunkskunk]

I know its a slightly diffrent animal, but I run an electric bike at upto 4 horsepower. Its a hub motor, so no gears. After several thousand miles, the only major wear was to the rear tire. I was running too small and too cheap a tire back there. Oh, and some spoke breakage from cheap spokes and too much power. No problems now running 14 guage DT swiss spokes and a good rear tire.

There's no problem adding the extra power, if you do so responsibly.

 

[duivendyk]

A lot of people have opinions about things they know little about,usually negative ones,rather like the NIH syndrome.The NV hub is on the heavy side,other internally geared hubs are not all that light either.I suppose he likes deraileurs.Severe vibration in frame mounted bikes with light frames is a cause for concern in my opinion, but these sweeping blanket condemnations are stupid,it all depends on the system inplementation.

 

[loquin]

Also, keep this in mind - the small engines are able to produce more horsepower than a human can maintain. However, humans can GREATLY exceed the torque that one of these motors can produce. A motor's torque is smooth, whereas a human's is pulsed. If a 200 pound rider is standing up while peddling, his entire weight is supported by first one, then the other peddle, which works out to (assuming a 7 inch radius on the peddles) about 116 foot-pounds. A Honda GX35 motor provides about 1.4 lbf·ft at 5,500 rpm, and geared through one of Staton's 18.75:1 gearboxes, outputs about 26.25 foot-pounds from the gearbox.

And, there is ZERO net 'upwards force' on the rear fork. This is because any force caused by the motor 'pulling upwards' is exactly balanced by the down-rods from the motor to the rear axle.

BTW. The GX50 has about 50% more torque than the CX35, so, the 26 foot pounds would be raised to about 40 foot-pounds. And, that's still much less than a human can produce.

 

[Alaskavan]

I'm not sure I understand the question. Things wear out comensurate to the amount and style of use. You could put a motor on a bike and have it last forever (don't ride it). You can totally destroy a bike without a motor in short order (ride like me). I have over 3,000 miles on my trike. The brake pads are pretty worn, and I think I have a bearing starting to go. Oh well.

 

[duivendyk]

Gradual deterioration is one thing,catastrophic failure in the wrong place (an intersection for instance) quite another,greater speed means that the performance of bearings increases in importance (regular lubrication,but the forces can actually be lower as Loquin has pointed out.Brake performance is certainly more critical,esp the front brake!,more mass and more speed and a high CG and therefore more weight transfer to the front.Practice emergency braking!.

 

[graucho]

Well lets see....LOL
9,556 threads, 103,270 Posts, and 1,623 Active Members can prove your mechanic friend wrong.

 

[pacs50ccmonster]

i agree is all about how you take care of things check things often dont ride as fast as you can down bumpy roads just basic maintance and my g>> watch for cars otherwise your bike may not need to last just my 2cents too many peeps gettin hurt these days

 

[SirJakesus]

I agree with most of you guys. It all depends on your system and how you ride it. If you're nice to the bike it'll wear as a normal bike would just faster since you're traveling much greater distances than when pedaling. Weight increase on most systems isn't considerable and is well within most bicycles designed load. It can definitely be done reliably as long as it's made well and not abused.