V3 P-85 Was Dynoed

Smaller than 32? you run into diminishing returns and can end up making your bike slower, you need torque to maintain or increase speed.
The problem that I run into with my 100cc is that I immediately get up to top speed and then I have nothing left on my final drive ratio after the porting job it has a tendency to Rev Way higher than I'm comfortable with because naturally the stock internals aren't balanced for 9,000 RPM, but in its current condition on confident that if I could find an even smaller sprocket then I would be able to get up the top speed if I had something like a 26 or a 28 tooth sprocket because even under wide open throttle at a 35° incline it's still flies all the way up to the top of the RPM range and then I'm stuck having to let off so I don't risk throwing a piston through the top of the motor
 
The problem that I run into with my 100cc is that I immediately get up to top speed and then I have nothing left on my final drive ratio after the porting job it has a tendency to Rev Way higher than I'm comfortable with because naturally the stock internals aren't balanced for 9,000 RPM, but in its current condition on confident that if I could find an even smaller sprocket then I would be able to get up the top speed if I had something like a 26 or a 28 tooth sprocket because even under wide open throttle at a 35° incline it's still flies all the way up to the top of the RPM range and then I'm stuck having to let off so I don't risk throwing a piston through the top of the motor
Put into perspective when I open up the throttle wide open it slips me back on my seat with a 32 tooth sprocket
 
Put into perspective when I open up the throttle wide open it slips me back on my seat with a 32 tooth sprocket
If my math is right, you should hit 60mph @ 9,000rpm, if you're topping out at 37mph and you are actually @9,000RPM, your clutch is slipping hard.
 
You're out of power to go any faster. 37mph is actually pretty good for a YD/LD 100 engine. They aren't known for their top end speed. As Wyvern said, you are going to gear yourself out of the powerband and actually see a loss in performance.

A phantom 85, completely stock, will get 99% of riders to 45mph with a 36 tooth sprocket on a 26 inch wheel because it makes 5hp at 9500rpm. Smaller people tend to reach 50mph. @DAMIEN1307 has a stock Phantom on his 26 inch setup and has no problem achieving those speeds. The Avenger 85 makes 4hp at an even higher RPM (11,000 IIRC). and can also achieve similar speeds with the right setup and rider. Both engines make a ton of torque very very low in the RPM range, which is why the pull so well off the line just like a YD/LD, but they also make a higher peak HP and at a higher RPM.
 
The problem that I run into with my 100cc is that I immediately get up to top speed and then I have nothing left on my final drive ratio after the porting job it has a tendency to Rev Way higher than I'm comfortable with because naturally the stock internals aren't balanced for 9,000 RPM, but in its current condition on confident that if I could find an even smaller sprocket then I would be able to get up the top speed if I had something like a 26 or a 28 tooth sprocket because even under wide open throttle at a 35° incline it's still flies all the way up to the top of the RPM range and then I'm stuck having to let off so I don't risk throwing a piston through the top of the motor

I truly would love to see such an event as you going up a 35° dirt hill. Because it takes specialized built motorcycles to do such a feat. The 3 steepest paved streets in the world are only 20.3° which is a 37% grade. A 35° hill would be a 70% grade.
 
I truly would love to see such an event as you going up a 35° dirt hill. Because it takes specialized built motorcycles to do such a feat. The steepest paved streets in the world are only 20.3° which is a 37% grade. A 35° hill would be 70% grade.
I apologize maybe I meant a 35% grade and not a 35° I'm not even 100% sure as to the specific configuration of the motor although I did have pictures posted The black one is the 100cc that I'm using stalk the motor was advertised as 6,500 RPM though after opening it up with a Dremel I'd say it's probably closer to 8:00 or 9,000 RPM GPS has shown with my ADCC that I could do 37 mph in conjunction with the speedometer that I had on there as well it was within a 1 mi per hour tolerance, My bike uses skinny tires I do not write it on the dirt as a general rule because they're 700C hybrid
 
If my math is right, you should hit 60mph @ 9,000rpm, if you're topping out at 37mph and you are actually @9,000RPM, your clutch is slipping hard.
I'm still using the totally stock clutch and a good chance is that it has those orange sandstone pads in there but I do have 115 lot of the black and white ones waiting to go in when I finally eat these ones up and then I'll be taking the clutch friction disc and I will be cutting grooves into it so it grabs them
 
I truly would love to see such an event as you going up a 35° dirt hill. Because it takes specialized built motorcycles to do such a feat. The 3 steepest paved streets in the world are only 20.3° which is a 37% grade. A 35° hill would be a 70% grade.
The main question I have is what configuration or style of motor is this because it was only advertised as a 100 cc and the seller said it was a 7.5:1 compression ratio
 

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I apologize maybe I meant a 35% grade and not a 35° I'm not even 100% sure as to the specific configuration of the motor although I did have pictures posted The black one is the 100cc that I'm using stalk the motor was advertised as 6,500 RPM though after opening it up with a Dremel I'd say it's probably closer to 8:00 or 9,000 RPM GPS has shown with my ADCC that I could do 37 mph in conjunction with the speedometer that I had on there as well it was within a 1 mi per hour tolerance, My bike uses skinny tires I do not write it on the dirt as a general rule because they're 700C hybrid
Also would having a 700C tire on the front of the bike affect the final drive ratio for the 26-in rear wheel?
 
That is true, my bike is under 60lbs, and it's 100cc, hand ported with a mildly tightened squish gap and I weigh 160lbs, I also have a stock 80cc with a 2inch PVC ram air intake that made a massive difference on mid and high range HP and RPM, cleaning the castings up and port matching the china gaskets on the bottom of your cylinder will make a huge difference as well as removing your stock muffler cap, add a 35$ carb from Amazon(2 inch intake side for the filter and 22-23mm Venturi will wake it up)
The gasket for the bottom end that your holding was put on backwards at some point. That in itself will reduce power greatly. See the impressions that it left. Either that or your tranfers have got a wierd casting angle
 
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