New to Motorized Bikes!

[ez dave]

cromo frame good brakes and safety wire. btw 45 on a motorized bike feels much faster, most people dont even want to see 40. keep in mind also power assisted bicycles have a maximum allowed speed of 20 mph, that is a federal law, even though i often break it. when the police ride behind me i just slow down and start pedaling. butterbean has some good advice. what are the laws in tx, just curious.

 

[butterbean]

Chromoly isn't the only good frame to motorize. American steel if you can find it, and even some department store bikes have solid frames. Not saying the rest of the parts on a department store bike will be solid, but I have a cranbrook frame in my basement that's almost 4 years old, and held my 280 lb butt just fine.

 

[Donavan321]

Department store frames

Chromoly isn't the only good frame to motorize. American steel if you can find it, and even some department store bikes have solid frames. Not saying the rest of the parts on a department store bike will be solid, but I have a cranbrook frame in my basement that's almost 4 years old, and held my 280 lb butt just fine.

I can AGREE with this statement and back it up. I have used several Huffy bicycles. Cranbrooks, as well as Santa Fe Cruisers. I have not had ONE problem with them breaking down, falling apart, frames cracking, etc. I've used alot of "department store bikes" for my builds since I'm on a REALY tight budget. I ride it until/if it breaks down. At that point, I can get everything I need locally from some local bike guys. A guy I know runs a bike shop and I can get STEEL(usually) complete rims..cassettes and everything included for 10-$15 and he trues them up for a bargain price as well. So, I will continue using department store bikes!

 

[TABrinn]

I have used several Huffy bicycles. Cranbrooks, as well as Santa Fe Cruisers. I have not had ONE problem with them breaking down, falling apart, frames cracking, etc. I've used alot of "department store bikes" for my builds since I'm on a REALY tight budget. I ride it until/if it breaks down.

I like the look of the Huffy Millennial Cruiser at Walmart. Anyone know if I could order a bare frame? Has enyone experianced frame failure? If we can find the most likely places to crack, gussets could be welded in for additional strength. Some sort of suspension is a must to absorb some of the abuse from the road. I love tho look of the Springer front fork, but also want to work out some rubber bushed motor mounts to absorb vibrations from the engine. Its amazing to think how much vibration stresses, fatigues and eventually leads to structural failure.

 

[butterbean]

Most times when people try the rubber bushings, it causes more vibration and has actually caused a few frames to crack.

 

[V 35]

You are asking a lot ! First off, take a look at the wheels on a $ 100 bike, pay attention to where the rim is seamed, a couple spot welds at best, now consider, you want to operate at about 5 times the rated speed, for long periods of time . Worksman wheels are probably the toughest in the business [ check out a Hot Dog Cart, if you can't find a bike handy ] Some Mountain Bike Wheels are very tough, double wall, 14 GA spokes, but are built for impact resistance, not speed. As for reliability, I figured on starting with a 2 stroke, than gravitate to a four stroke for more reliability.

From what I've seen, the 2 strokes are actually more durable, and reliable, hard cornering starves engine for oil = short bearing life
Transmissions seem failure prone, a four stroke has too many jackshafts and other components to be reliable . If the store boughts are short lived, think about how long a cobbled together home made will last. When it comes to engines, at least get a horizontal shaft, a vertical shaft is lunacy. Look at lots of pictures, if cheap is your only goal, buy a used moped. If you want a sweet cruising, reliable bike, be prepared to spend what it takes, and as you know from your other builds, it * can * get expensive . The fact that your an A P means you have an eye for quality, and safety, don't get hurt saving a few bucks, its not worth it.

Go Fast / Crash Hard

 

[professor]

TA, you have gotten real good advise here.
I think your expectations are out in space.
The Briggs will not propel you to 60.

I run a 212cc and it will stay with traffic or just ahead, but I have to work at it and I have 3 gears, moped wheels,and full suspension.
It is wound out at 4400 rpm and a tad over 40 mph.
Rarely do I ever do that.
Set up the way it is - 9 hp is on tap and I cruise around at the motor's sweet spot-25-28 mph.

Legally- it is a moped.
Mopeds are for the side of the road and 20 something mph is safer than being IN traffic.

Your desire requires a real motorcycle- something 175cc and up.

And I agree, motorcycles are too dangerous BECAUSE you then will be IN traffic.
The very place you intend to ride?

Long ago when I rode motorcycles, the temps here in Buffalo would hit 85 or a bit more, and I could not keep from becoming a sweat ball (leather jacket, boots, helmet, always) on a motorcycle, no matter how fast I went.

Doesn't it hit a hundred often in Texas? Are you sure you want to dump that car?

 

[keatonx]

A 212cc preddy should be able to hit 60mph, and a 4.5 briggs should atleast approach.
I've gone atleast 55 or so on my lawnmower bike, according to an online go cart speed calculator. That's with a 140cc 2 stroke mower engine (stock 4hp but it has some work for sure). But cruising at that speed? Daily? You will die for sure, unless you use a proper motorcycle frame. My lawnmower bike is straight as an arrow at high speed, but I've only taken it that fast once, maybe twice. It's a very sketchy bike, so I rarely ever ride it anyways.

Converting a vert. Shaft to a horizontal won't be perfect and you'll probably still get some oil starvation. Either way, maintaining 60mph daily with a cheapo briggs will kill the engine within a few weeks probably, unless you gear it so it isn't over-revving so much (anything over 3600 will eventually cause the big end bearing to heat seize, and throw the rod)

And what about flywheel explosions?? Happens all the time with the racing mower guys; the cheap cast iron flywheels could fly apart and kill you. But since you have a mower engine it'll be an aluminum flywheel, which causes problems of its own. My 2 stroke mower bike has an alum. Flywheel and it runs VERY rough. I once tried
Starting a 4 stroke briggs 6.5hp without the blade acting as a flywheel and it kicked back almost every pull. It would tear the handle out of my hand and smash it into my ribs painfully hard. Even my lawnmower bike kicks back pretty bad at times; I need to slowly pull it to TDC, then pull it to prevent it from kicking back. (Old powersport trick)
If you search up "lawn mower blow up" or something like that, there's one video where the guy actually removes the governor so it revs wide open. It threw a rod in a few minutes. So unless our stretch of 65mph highway is 1/2 a km long then you're asking for trouble

Also, a stock briggs with no governor will only rev to 5500rpm or so, because the valves start floating.

 

[Donavan321]

Bikes

A 212cc preddy should be able to hit 60mph, and a 4.5 briggs should atleast approach.
I've gone atleast 55 or so on my lawnmower bike, according to an online go cart speed calculator. That's with a 140cc 2 stroke mower engine (stock 4hp but it has some work for sure). But cruising at that speed? Daily? You will die for sure, unless you use a proper motorcycle frame. My lawnmower bike is straight as an arrow at high speed, but I've only taken it that fast once, maybe twice. It's a very sketchy bike, so I rarely ever ride it anyways.

Converting a vert. Shaft to a horizontal won't be perfect and you'll probably still get some oil starvation. Either way, maintaining 60mph daily with a cheapo briggs will kill the engine within a few weeks probably, unless you gear it so it isn't over-revving so much (anything over 3600 will eventually cause the big end bearing to heat seize, and throw the rod)

And what about flywheel explosions?? Happens all the time with the racing mower guys; the cheap cast iron flywheels could fly apart and kill you. But since you have a mower engine it'll be an aluminum flywheel, which causes problems of its own. My 2 stroke mower bike has an alum. Flywheel and it runs VERY rough. I once tried
Starting a 4 stroke briggs 6.5hp without the blade acting as a flywheel and it kicked back almost every pull. It would tear the handle out of my hand and smash it into my ribs painfully hard. Even my lawnmower bike kicks back pretty bad at times; I need to slowly pull it to TDC, then pull it to prevent it from kicking back. (Old powersport trick)
If you search up "lawn mower blow up" or something like that, there's one video where the guy actually removes the governor so it revs wide open. It threw a rod in a few minutes. So unless our stretch of 65mph highway is 1/2 a km long then you're asking for trouble

Also, a stock briggs with no governor will only rev to 5500rpm or so, because the valves start floating.

*Really(my mistake) As far as rubber mounts and all that. I've never cracked a huffy frame using a china girl. My fastest bike I built went about 46mph max speed, it was on a cranbrook frame. Rode it like that for a REALLY long time, no blown bearings, no wrecked spokes, etc. Rubber mounts: BAD idea, as mentioned above they cause more vibration and can put more stress on the mounting studs causing them to SNAP off, usually in the block, requiring a drill bit and a tap....NOT something you want to mess with. 60MPH is generally UNSAFE on a MAB, and it also attracts all kinds of unwanted attention from the police, again, AVOID! Most modern huffy bikes are built a lot better today then they used to be, back in the day they used nylon balls instead of metal balls for the bearings! PLASTIC bearings! Good luck!

 

[keatonx]

Donovan321 I think you might be confusing me with the OP