AMERICANS: Would you buy a 125cc motorcycle for the street?

[Daschicken]

Originally Posted by saturndude

I commuted on a 1970 cb100 for many years until 5 years ago. It was an awesome bike and got about 90mpg and maxed out at 67mph

CB100s actually look really cool! It has a close resemblance to the honda dream 50, which is another bike I WANT.

Originally Posted by saturndude

Now I have a Suzuki sv650 that I commute with, splitting lanes both ways everyday down the 101 and 405 freeways, I feel comfortable at about 30-35mph when traffic is not moving. I have a narrow box no wider than me, no bar end mirrors keeps me narrow, about 18" wide. I always go faster than traffic for safety, 90+mph when traffic is moving fast.

That sounds really dangerous. I haven't lane split before, but I wouldn't go faster than maybe a 15 mph difference. Bikers riding by traffic at high speed differences is pretty much the main reason car drivers oppose lane splitting, and why I can't do it in Georgia!

Originally Posted by saturndude

6 gears, liquid cooled v twin with about 90hp that gets 55mpg easily (could do much better if driven for hypermiling I bet) got mine for $1300 used, dead reliable (now at 70k miles with just regular maintenance), weighs under 400lbs.

My little brother wants an SV650, and I mostly support that decision. That MPG sure would be nice, my VFR400 doesn't get that good(yet). I have looked up cruising RPMs for SV650s in the past, and they are pretty low. The problem is the power, its too much to be able to enjoy often without breaking laws.

[gone9]

I would love to have an old Honda for fuel economy. In the summer I would ride it everyday. I’m only 9.9 miles from work currently. In the winter I have the commuter car or the pickup with 4wd. We get ALOT of snow here in northern Idaho to say the least.

But a little motorcycle would be amazing in the summer.

Pros:
Better parking
Better traffic management
Better economy
Cheaper cost of ownership


Cons:
Exposure to elements
Room for suppplies/people
Exposure to other motorist

[woodsrat]

Renovating an old Honda using one of the inexpensive and reliable Chinese replacement motors isn't terribly difficult, saves you money on licensing and insurance since it's an old bike and actually gives you a superior machine to the originals in many ways (more power, 12v. electrics, CDI ignition).

I own three and have helped build a half-dozen more. All but one use a simple battery-less AC lighting system that's reliable and puts out excellent light.

Nearly all have been built using the horizontal 125 Lifan engines in either semi or manual clutch versions. The first I bought six years ago were $265 to your door and although they've gone up to around $350 they're still a tremendous bargain.

The easiest to convert are any of the Hondas that were originally equipped with 50/70cc overhead cam engines. Next easiest (requiring only minor clearance modifications with a grinder) are the 50/90cc overhead valve push rod engines. The bikes originally equipped with overhead cam 90cc engines require an inexpensive adapter kit from Dr. ATV--or some minor welding and modifications to mount the engines.

We've built them from Honda Passports, CT-90's, CT-200's (OHV push rod Trail 90's) and one from an original C-100 (OHV push rod 50). All were cheap to build and most of the money went into replacement of rusty or worn-out parts. Find a good rust-free unit and it'll save you a bunch of time and money.

These old mostly sheet metal frames can indeed rust out so inspect them carefully before you buy.

The bikes with AC lighting end up weighing around 175 lbs. although a C-100 I recently built weighs under 150 lbs. The 50cc step throughs had the lightest frames of them all.

You can use the stock leading link or the hydraulic CT-90/110 forks (if they're not rusty) or get a fair set of new replacements from eBay for around a hundred dollars. I've been adapting forks from XR/CRF-80/100's by lengthening the steering stem. Many other small Honda forks use the same steering head bearings and can be easily adapted.

eBay or suppliers such as Dr. ATV will get you the majority of the parts you need. Inexpensive Chinese pit bike parts like pipes can be easily fitted to replace the usually rusted out stock exhausts.

On the 125's I use a 22mm Mikuni that's common and cheap on eBay for under $50.

No, these aren't the liquid cooled six speed wonders available everywhere but the U. S. but on the other hand they're light, simple and fun to ride. Geared the way mine are with stock 125's they'll run right at 60+ MPH and will cruise all day long at 50+. I've ridden mine from Indy to the Smokies and back comfortably.

I can't say enough good about these builds and since American Honda has chosen to abandon the lightweight motorcycle market except for the minis it's the only game in town other than the KYMCO K-Pipe (which I also own).

[Stubby79]

Originally Posted by woodsrat

No, these aren't the liquid cooled six speed wonders available everywhere but the U. S. but on the other hand they're light, simple and fun to ride. Geared the way mine are with stock 125's they'll run right at 60+ MPH and will cruise all day long at 50+. I've ridden mine from Indy to the Smokies and back comfortably.

What kind of top speed are you looking at on a hill?

I have some cheap brand 110cc on my bike, semi-auto 4-speed...doesn't go anywhere near that fast. Clutch is one limiting factor.

Trying to decide if it's worth upgrading again.

[woodsrat]

During the Smokies trip (in the company of childhood friends on a Harley bagger and a Tri-Glide--talk about an odd bunch) most of the hills could be pulled in third gear. I'm running 17/36 gearing.

I recently rebuilt the first one I put together after five years of service and upped it to a TB 141cc kit with a cam from TBoltUSA. On a ride into the hill country east of Louisville with a friend on his 125 Lifan powered CT-200 I could pull hills in high gear going away that had him in third. The increase in torque is awesome!!

It worked so well Vince, the bossman at TBoltUSA, talked me into a full TB top end for the Lifan 125 I put into the K-Pipe. This'll include a roller rocker head with a larger intake valve, a matching cam and a 26mm carburetor. It'll be going on ASAP.

Surprisingly other than an appetite for premium gas my mileage is about the same on the 141 as it was on the 125. It's a lot more fun to ride, too!! Originally I used a 15/36 gearing combo and wheelies away from a light were a problem so I went to the 17/36 which both eliminated the unwanted wheelies and gave me a lot more cruising/top speed. Now with the 141 the wheelies are back!!

The extra torque of this motor immediately smoked the stock Lifan clutch but a complete heavy-duty unit fixed that problem.

[Daschicken]

I think the level of participation in this thread has all but secured it a spot in the top 25 threads list for this year, maybe even top 5.

Originally Posted by ProDigit

Hypermiling on a small bike does very little, since it has no weight to keep it rolling.
Believe me, I've tried, I used to have a roketa m05 127, a 4 SPD manual motorcycle, which I geared from the 44 tooth rear sprocket to a 34 tooth the smallest I could equip it with, and the max I could get out of those air cooled bikes is 100-125MPG.
It got 96MPG on the highway doing 55-60mph, depending on the wind.
And 120 mpg doing 40mph at 3k rpm.
Any heavier gearing, and the bike would accelerate slower than a 50cc from a stop.

I somewhat agree with this, bikes don't seem to get the massive fuel economy increases that cars do when hypermiled. I haven't been able to get much higher than normal numbers on my bikes, but seem to be above average. Most of the problem with that is I am riding with my dad for 99.9% of motorcycle trips, and he is not a hypermiler, so I have to adjust my riding style to keep up with him. When I am in the car and have to follow him, my highway mpg is pretty much limited to 40 best case. Normally I get 45+ on highways.

Back before a former coworker and motorcycle buddy died riding to work, I was permitted to ride to work on the bikes. My bike of choice at that time was a 1999 VFR 800 due to its replaceability, weight, and lack of desirability. My fuelly average shows 43.8 MPG for that bike. On the one tank I was able to get through doing ONLY work commutes on the bike, including plenty of full throttle acceleration, I got 44.1 MPG! To compare, my V6 accord doing only those work commutes(plus one longer city trip) got 32.9 MPG. If I had toned down the acceleration and did more engine on pulse and glide with the VFR 800 I probably could have passed 50 MPG all city! That bike takes a long ass time to warm up too, so if I had blocked off some of the radiators it could have gotten even better.

I think the lesson to be learned here is that bikes can EXCEL in mileage for lower speed trips, and that lots of accelerating and decelerating doesn't hurt bike mileage as much since they weigh a lot less, and then it gives the engine a chance to be more efficient for a change.

Back before the CBR 250RR article on wikipedia disappeared, I remember it saying that the 250RR was capable of 94 mpg at 60 km/h(37 mph) constant. A quick look on wikipedia on the CB250F hornet(similar engine) says it can do 153 mpg at 60 km/h. (Have seen that number say 80 mpg before, so....?) Honda Dream 50 can apparently do 200 MPG at 30 km/h(19 mph). Your 40 mph mpg sounds pretty low, maybe the engine is running at too low an rpm? How much throttle are you using to maintain speed?

[ProDigit]

You'd have to make the distinction between mpg us, and mpg imp.
A lot of mpg quotes from the factory weren't always feasible, like, yes, you could get 125+mpg on a 125cc, but only in a lab, on a constant speed, on a dyno. Not anywhere near real world experience.

Mpg somewhat goes directly opposite to fun factor.
It seems to me,if your final gear is short, and acceleration in it is peppy and fun, your motorcycle will do below 66mpg, pretty much regardless of engine size.
80mpg is normal acceleration, and 100+mpg is rather tall hearing with sluggish acceleration,that would make a great hypermiler bike.

Anything below 50mpg gives near to front-wheel-in-the-air kind of acceleration and any bike that has track power (think 660cc racing engine, or higher) has bottom mpgs in the 30s.

[cRiPpLe_rOoStEr]

Originally Posted by Daschicken

I somewhat agree with this, bikes don't seem to get the massive fuel economy increases that cars do when hypermiled.

Sounds like a good excuse to think of a Honda CG 125 or similar as the "poor man's Prius"

[latrom]

I had a 125cc chinese scooter which I bought for 400eur. It was amazing. 2-3 l/100 km. I could take the groceries to home with it and also carry my wife. Parking was not a problem.

[sendler]

I can squeak out 5% better fuel economy on my 2011 Honda CBR250R than I get on my 2013 PCX150. Both are over 100 mpgUS, 42.5 km/L, 2.35L/ 100km. But most "normal riders get 75 mpg on the CBR250R and still get 100 on the PCX. I did 99.5 mpgUS for my 1,000 mile/ 23 hour trip on the CBR in bad weather. The PCX will top out at 67 mph with sliders instead of rollers. The CBR can hit 92 mph, 150 kph stock. A bit faster with longer gearing. Most of the modern bikes now have fuel injection, catalyst, and O2 sensor, so they don't stink up the place. And start first try and run perfect in any weather.
.
2018 CBR300R Overview - Honda Powersports
.
2018 PCX150 Overview - Honda Powersports
.