JerboaJohn
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that pipe won't hold up to pushing esp at the elbow.maybe something directly to the seat post,,
I am thinking of a 6.5hp rear drive.
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it would be easier to have 2 and make them a live axle
or just put a single wheel in the rear and balence it. (might have to midify it, as the engine would be offset)
i would try to connect it on the back axle, as it would be better for the brut force of the 212
FNTPuck
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You do not want a 50+mph 212 pusher trailer. Trust me. You will jacknife and send yourself flying on the first test ride. Around 20mph should be the limit.
FWIW, you won't get anywhere near there with 10-13" tires anyway without serious engine mods, even with a TQ converter. Won't have the RPM needed.
Quick questions you need to ask yourself for your proposed 50mph setup:
- What engine mods? It will take 6k or more RPM to do that with a 13" tire, and a stock 212 is 3600. For over 5k rpm you really need the billet flywheel and stronger valvesprings as a minimum
- How will you attach it? 6.5hp pushing on the weak little stock seat post won't last, it WILL crack right at the joint unless you can weld and gusset it.
- How will you gear it? A 13" tire is too small for top end unless you have a race built 212 for very high RPMs. Even with a .9 overdrive you are looking at a ~6500 rpm setup to do 50mph with a barely usable gearing ratio and it will be a dog at low speeds.
- How will you STOP it? Pusher trailers usually have no brakes. Will you add trailer brakes? Do you really want to be doing 50mph on a bicycle with an additional 50+lbs of weight aggresively pushing you forwards and try to stop it with CALIPER brakes??? Not a chance. You need bare minimum drum brake hubs and preferably disc brakes.
- How will you make the connection to allow movement for leaning, hills, bumps etc? If you fix it directly with no joints or swivels, it will snap even faster.
FWIW, you won't get anywhere near there with 10-13" tires anyway without serious engine mods, even with a TQ converter. Won't have the RPM needed.
Quick questions you need to ask yourself for your proposed 50mph setup:
- What engine mods? It will take 6k or more RPM to do that with a 13" tire, and a stock 212 is 3600. For over 5k rpm you really need the billet flywheel and stronger valvesprings as a minimum
- How will you attach it? 6.5hp pushing on the weak little stock seat post won't last, it WILL crack right at the joint unless you can weld and gusset it.
- How will you gear it? A 13" tire is too small for top end unless you have a race built 212 for very high RPMs. Even with a .9 overdrive you are looking at a ~6500 rpm setup to do 50mph with a barely usable gearing ratio and it will be a dog at low speeds.
- How will you STOP it? Pusher trailers usually have no brakes. Will you add trailer brakes? Do you really want to be doing 50mph on a bicycle with an additional 50+lbs of weight aggresively pushing you forwards and try to stop it with CALIPER brakes??? Not a chance. You need bare minimum drum brake hubs and preferably disc brakes.
- How will you make the connection to allow movement for leaning, hills, bumps etc? If you fix it directly with no joints or swivels, it will snap even faster.
bike4life
Well-Known Member
A 212cc can put out 3500watts of power. I looked at harborfreights 212cc generators and they put out 3500 running and 4000w starting. Plus these engines still have the governors installed. Now your lil 66cc machines put out about 700w, as hf tailgator generator is about 66cc and puts out 700w. So with your 66cc, u can prolly get 30mph at least. Now how can u tell me that i cant get 50mph eventhough my engine has around 5 times the power output. I did buy a torque converter, so shouldnt that handle the gearing. Look momentum = velocity x mass. So i am skinny, around 135lbs and the bike is standard weight and the trailer w/ engine about 100lbs. Therefore the total mass is 235lbs + bike. A normal person weighs 220lbs and the 66cc is 15lbs which makes 235lbs + bike. Therefore, the masses are the same and at the same speed, my pusher and your motorbike have the same momentum and therfore require the same impulse to brake. I am not really concerned about braking. Also i am building a hitch system out of thick plate steel and the arm is not iron pipe but some beefy channel stock. BTW i have no problem welding and gausseting random stuff, i am fabricating my own pillow block bearings to save cost!!! What i need to know is i just bought a torque converter and what 2ndary sprocket should i use coupled with a 13" or 10" tire to get 50mph. Thanks!
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FNTPuck
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What I'm saying is, even if for some strange reason you would WANT to, you CANNOT get 50mph out of a stock 212 with a 13" tire. There are too many holes in your logic to even know where to begin but I am in a good mood so instead of just criticizing I will explain it.
Ignore all HP, TQ, and weight and simplify it down to the basics to understand better. Top speed is a function of RPM and gearing - how fast your motor can spin, and the gearing that translates that into rotation of your drive wheel(s). Your tire height is part of that gearing. One rotation of a 13" tire is exactly half of a 26", so you would already need DOUBLE the RPM of the engine to make the same speed with the same gearing.
If you want the numbers, a TQ converter output at max gearing is roughly 1:1 (some are .9 and actually have a slight overdrive, so you can add 10% if you want). That means at max throttle your gearing is basically the same as with a centri clutch and the converter is effectively running at 1:1 input
utput. You said it has a 12t on the driver, and with a 54t rear (which is a 9" diameter sprocket and is just about the max you can fit on a 10" wheel) squeezed on that small 10" tire for a PITIFUL low torque 4.5:1 gear ratio you will max out at a whopping 24mph - rounding up. If you replace the 12t with a 10t to get your gear ratio up, and bump that rear sprocket down to a 50t with a larger 13" tire for some higher top speed, it gives you a slightly better but still crappy 5:1 ratio and squeezes out 28mph at the governed 3600rpm. If you reduce gearing any more than that to get higher top speed, you likely won't even be able to accelerate from a stop without pedaling it.Now do you understand why a low rpm 212 with a tiny tire won't do 50mph without a ton of rpms?
bike4life
Well-Known Member
Heres is what i was saying I am gonna run the engine at 3600rpm. I did the math and with a 10" tire and a 10t sprocket to a 25t rear sprocket the math works out to 42mph. With a 13" tire and same gear ratio that works out to 55mph. The torque converter will help me accelerate by and then when i want to go fast i can go fast with a 1:1 torque converter at peak.What I'm saying is, even if for some strange reason you would WANT to, you CANNOT get 50mph out of a stock 212 with a 13" tire. There are too many holes in your logic to even know where to begin but I am in a good mood so instead of just criticizing I will explain it.
Ignore all HP, TQ, and weight and simplify it down to the basics to understand better. Top speed is a function of RPM and gearing - how fast your motor can spin, and the gearing that translates that into rotation of your drive wheel(s). Your tire height is part of that gearing. One rotation of a 13" tire is exactly half of a 26", so you would already need DOUBLE the RPM of the engine to make the same speed with the same gearing.
If you want the numbers, a TQ converter output at max gearing is roughly 1:1 (some are .9 and actually have a slight overdrive, so you can add 10% if you want). That means at max throttle your gearing is basically the same as with a centri clutch and the converter is effectively running at 1:1 input
Now do you understand why a low rpm 212 with a tiny tire won't do 50mph without a ton of rpms?
Well, let's see
You have a 3600rpm engine that makes 6.5hp,
my suggestion would be to rework the govener so it activates at 5500 rpm. All you have to do is play around with the spring (it has 6 holes, so you have 6 areas to modify the govener to engage later)
That will give you more top end and you can gear it a bit lower and not have to modify the govener in any way. It's a win win imho. I've ripped out governors in nearly all my engines (with the exception of my 97cc and the 5hp techumseh, I bypassed them instead)
Your engine will not explode at 3601 rpm, it's just a standard they set it at for machinery (ie pressure washers, tillers, snowblowers)
Any way, prove us all wrong and make it do 65
Good luck!
You have a 3600rpm engine that makes 6.5hp,
my suggestion would be to rework the govener so it activates at 5500 rpm. All you have to do is play around with the spring (it has 6 holes, so you have 6 areas to modify the govener to engage later)
That will give you more top end and you can gear it a bit lower and not have to modify the govener in any way. It's a win win imho. I've ripped out governors in nearly all my engines (with the exception of my 97cc and the 5hp techumseh, I bypassed them instead)
Your engine will not explode at 3601 rpm, it's just a standard they set it at for machinery (ie pressure washers, tillers, snowblowers)
Any way, prove us all wrong and make it do 65
Good luck!
FNTPuck
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Good, because it wasn't for you. He already stated he wants to keep the engine stock with 3600rpm governor. He isn't getting anywhere near 55mph with a stock 212 with a $50 tq converter on a push trailer. Period.
bike4life
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ok ill remove the governor. can i just bypass it instead, seems like less work, just ziptie the lever thing back. The only reason y i didnt want to remove it was b/c i thought the engine might get damaged. Is it risky/will the engine get destroyed if i do so?? What is the max rpm i can run this thing at (continously) before i start screwing things up.
You
You engine will not explode, but if you take care if it (ie CHANGE THE DAMN OIL WHEN ITS BLACK) you will not experience the shorter life span.
I tired the zip tie trick on my baja before I took out the govener and it works-ish. You will still have the govener engage, but at a different time (just like moving the spring, as stated on my previous post)
Contuniusly (day and night) these engine will run at 3600 rpm for there entire life. But the valves float at 5500 rpm so that's like a secondary govener (imo)
I get that its your only engine (I was scared as hell removing the govener in my baja, but I managed to do it and no blown engine, only a blown light bulb lol)
And if you remove the govener your going to have to rework throttle linkage as you effectively thrown half of it away (agian not that hard to do, just intimating)
Hope this helps
Can bypass it, but its risky (I did it on my engines as I got them dirt cheap and could care less if they explode)
You engine will not explode, but if you take care if it (ie CHANGE THE DAMN OIL WHEN ITS BLACK) you will not experience the shorter life span.
I tired the zip tie trick on my baja before I took out the govener and it works-ish. You will still have the govener engage, but at a different time (just like moving the spring, as stated on my previous post)
Contuniusly (day and night) these engine will run at 3600 rpm for there entire life. But the valves float at 5500 rpm so that's like a secondary govener (imo)
I get that its your only engine (I was scared as hell removing the govener in my baja, but I managed to do it and no blown engine, only a blown light bulb lol)
And if you remove the govener your going to have to rework throttle linkage as you effectively thrown half of it away (agian not that hard to do, just intimating)
Hope this helps
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