HoughMade Cycle Works- mock up

  • Thread starter Thread starter HoughMade
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Still needs a few details- I am fabricating a cover that will go over the tank and make it look more pre -WWI, and plates to blend the engine mounting plate so it does not look so flat- but she hit 40 mph Saturday- with a 56 tooth sprocket- I have a 48 tooth....so far I have no interest in installing it.
 

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ocscully said:
HoughMade,
...The primary driver on the clutch bell of the GRUBEE is 35t engaging a 54t/20t stepped gear in the middle, the smaller 20t in the middle engages a 48t gear which drives the gearbox output cog 11t sprocket. I calculate the gear box to have a reduction of 3.7:1,...
ocscully
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Correct on all tooth counts- however, the ratio is 2.7:1, not 3.7:1- makes a world of difference.

Let's say the 35 tooth from the engine goes around 1000 times. How many times does the 54 tooth go around? 648 times. The 20 tooth keyed to the 54 tooth also goes around 648 times. If the 20 goes around 648 times, how many times does the 48 go around? 270 times. Therefore, for every 1000rpm that goes in, 270 come out= 2.70:1.

Now, plug that into the gear ratio calculator.

6000 rpm- 33.8 mph

7000 rpm- 39.4 mph

I'm a lawyer, not a mathemagician, so if I screwed that up, show me and I will admit my mistake ;)
 
HoughMade, I don't want to make you mad but,54/35=1.543, 48/20=2.4, 1.543X2.4=3.7032 so 1000rpm/3.7032=270.03672rpm. louis
 
Hey- finding out I screwed up the math ain't going to make me mad....

....yep- top speed a bit over 30 mph with the 56 unless you overrev it- possible.

I will now sit down and take my flogging.
 
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HoughMade said:
Correct on all tooth counts- however, the ratio is 2.7:1, not 3.7:1- makes a world of difference.

Let's say the 35 tooth from the engine goes around 1000 times. How many times does the 54 tooth go around? 648 times. The 20 tooth keyed to the 54 tooth also goes around 648 times. If the 20 goes around 648 times, how many times does the 48 go around? 270 times. Therefore, for every 1000rpm that goes in, 270 come out= 2.70:1.

Now, plug that into the gear ratio calculator.

6000 rpm- 33.8 mph

7000 rpm- 39.4 mph

I'm a lawyer, not a mathemagician, so if I screwed that up, show me and I will admit my mistake ;)
Click to expand...

I think you should knock off at least 30% for load & wind and a further 30% for incline.
 
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