Found the Hill my bike couldn't get up. Pics.

Backwoods

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So theres a hill near my house in Round Rock, the Frontier Hill, Frontier being the street name. The hill is literally the largest hill within 20 miles, easily. It gets steeper in steps, each about 30-50yds. About 4 "steps", the last one is only about 20yds but it's at like a 40° angle. It's a serious hill, even cars sometimes have trouble. This is that hill that you go up in low gear, 1st or 2nd.
I decided to see if my slightly molded 66 could make it up, it didn't. The hill is so long that by the time you get to the steepest point, the rpm has already dropped below the power band and it just doesn't make it. Had to get off the bike and walk it back down. It's the kind of hill that you smell things start getting hot just halfway up.
I am running a 41 tooth, I think it Might be able to make it with a 56 tooth sprocket, but I'm not trying to rip the spokes from my wheel. I also weigh 220lb, I'm not surprised the bike couldn't do it, but I just had to see.
I really want to get the Anbull 100cc(80 in American) and find out if the extra 10cc of air mix will get me up it. Mines currently at 69.5cc, the 100 would bring it to 79.4cc or something like that.

So for all who are curious, this hill seems to be the limit of the 66cc's torque. The 48cc prolly wouldn't have even got halfway. The 70cc made it nearly 80-85% of the way up.

The picture that seems far away, when I took it I was standing on a slight incline, the beginning of the Hill, it's a pretty long hill, about 250-300yds long, progressively getting steeper. So it wears the engine down on ever increasing angles before it ever gets to the hardest part.
 

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So theres a hill near my house in Round Rock, the Frontier Hill, Frontier being the street name. The hill is literally the largest hill within 20 miles, easily. It gets steeper in steps, each about 30-50yds. About 4 "steps", the last one is only about 20yds but it's at like a 40° angle. It's a serious hill, even cars sometimes have trouble. This is that hill that you go up in low gear, 1st or 2nd.
I decided to see if my slightly molded 66 could make it up, it didn't. The hill is so long that by the time you get to the steepest point, the rpm has already dropped below the power band and it just doesn't make it. Had to get off the bike and walk it back down. It's the kind of hill that you smell things start getting hot just halfway up.
I am running a 41 tooth, I think it Might be able to make it with a 56 tooth sprocket, but I'm not trying to rip the spokes from my wheel. I also weigh 220lb, I'm not surprised the bike couldn't do it, but I just had to see.
I really want to get the Anbull 100cc(80 in American) and find out if the extra 10cc of air mix will get me up it. Mines currently at 69.5cc, the 100 would bring it to 79.4cc or something like that.

So for all who are curious, this hill seems to be the limit of the 66cc's torque. The 48cc prolly wouldn't have even got halfway. The 70cc made it nearly 80-85% of the way up.

The picture that seems far away, when I took it I was standing on a slight incline, the beginning of the Hill, it's a pretty long hill, about 250-300yds long, progressively getting steeper. So it wears the engine down on ever increasing angles before it ever gets to the hardest part.
I built a hill climber 100cc and 66cc. Well motors. I swap back and forth depending on who I'm riding with. My 100cc is nitropropane powered and will climb any hill, even crash alley. It's super steep like your hill. Kinda expensive to run it, but it pulls like a darn bull. The 66cc will make it almost all the way, but I have to pedal a few times. This is with pipes and porting and changing timing etc.



Edit: oh and I run 10/44 gearing.
 
I live in the mountains. So I'm going to educate you on gradients. The 3 steepest known paved roads in the world are a 37% grade. They're located in Pittsburg, Ireland and New Zealand. A 37% grade is 16.25°. So you see a 40° hill would be an 88.9% grade hill. Impossible for any street vehicle to get up.


Go to your hill get a long straight edge such as a 6'+ level. Lay the level to where it runs with the hill. Then put a protractor on it to get a degree reading. Once you have a degree reading use this formula

Degrees X (20÷9) = % Grade.
 
I'm 6'2" and weigh 250 lbs, my bike weighs a 100 lbs. I use a 33cc 4 stroke engine that has 1.6 hp. I commonly go up hills such as the one you have at least 8 mph. What I have that you don't is a triple chainring shift kit. The reduction range is

66.79:1 to 16.25:1

This is how I'm able to do with a small engine what people with bigger engines can't do. So you may want to consider building a shifter.
 
I built a hill climber 100cc and 66cc. Well motors. I swap back and forth depending on who I'm riding with. My 100cc is nitropropane powered and will climb any hill, even crash alley. It's super steep like your hill. Kinda expensive to run it, but it pulls like a darn bull. The 66cc will make it almost all the way, but I have to pedal a few times. This is with pipes and porting and changing timing etc.



Edit: oh and I run 10/44 gearing.
I've even gone up the hill on Keysprings rd at the hairpin in Oak Ridge Tennessee. This may even be the steepest paved street hill in the world but it's only about 3 car lengths long. Keysprings road was designed to prevent a tank from coming up it during the time of the Manhattan Project. Its so steep that you have to lean forward to keep from flipping backwards. This road gets closed down during ice storms and heavy rains.
 
I've even gone up the hill on Keysprings rd at the hairpin in Oak Ridge Tennessee. This may even be the steepest paved street hill in the world but it's only about 3 car lengths long. Keysprings road was designed to prevent a tank from coming up it during the time of the Manhattan Project. Its so steep that you have to lean forward to keep from flipping backwards. This road gets closed down during ice storms and heavy rains.
This road?

 
That's the road but this video doesn't really show you how steep the hill is in the hair pin. Here's a second video going up Keysprings but it not very good. My nephew lives in Oak Ridge so I'll get some pictures of it. The hill kind of reminds you of when you built jumping ramps

 
I'd get a video of my hill, but I can't post it here and hard to film and ride. lol. I won't drive in my truck on it, people are nuts and always a crash from them driving like idiots on the blind crest.
 
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