Johnny5 wrote:WOW. I did not know that the fuel economy becomes so dismal with heavy Modding. As a newbie to bbk's, I'm sure glad I have a 1.3 gal tank. The Aero had half that.
Would it be safe to say that your fuel economy reflects the output of your build. Example. Stock your scoot made 3 HP, but now it makes 6hp. Would it in turn consume twice as much gas?
NNo its no were near that bad. And the goal for HP is much higher (naturally) 6hp just doesnt cut it.
I can point fingers at my carb, I could be running a 17.5 which was recommended but I had already bought a 19mm.
A BBK is surely worth the loss. I would go bigger if I could(I will.) soon.
But yes the fuel economy reflects on the parts you put on. A BBK requires a bigger carb to use the full potential of power.
Bigger carb/bigger jet = more gas consumption. You can gain speed/power by modding other things lowering the need for more gas, but with that you sacrifice low end/top end. Carb modding/intake is normally raw power. The other parts just balance/convert it.
'98 Yamaha Jog Cy50k
'96 "Frankenstein" Japanese Jog Cy50
once again the bear posts stupidity, not owning a performance scoot? i do infact own a 108cc full stroker aero which gets 30 miles "to the tank" and that is up 5mpg using an msd blaster coil
maddog wrote:once again the bear posts stupidity, not owning a performance scoot? i do infact own a 108cc full stroker aero which gets 30 miles "to the tank" and that is up 5mpg using an msd blaster coil
The only stupidity is you running your mouth and making unsupported claims to performance that no one has ever seen. At least I can prove my credentials. Of course your mouth is the only thing that runs fast around here and no one believes a thing you say anyway. Your coil claim is just proof your have no clue about how an engine even works.
Bear 45/70
'83 Aero 80 X 3
'84 Aero 80 X 3 '85 Aero 80 '84 Aero 125 X 2
'84 Aero 125 '84 Aero 125 X 2 '85 Aero 50
'85 Spree
We could/should spend some time here looking for contributing factors to poor economy. One thing to look at are production larger two stroke scooters. Bear's 80 and 125 cc scooters are no doubt getting better than 30mpg
Here's one idea:
Tuned pipes, when run below their design rpm point are a negative for fuel consumption and emissions. Timing between the vacuum and return pulse are mechanically fixed to the optimum RPM for which the pipe is designed. When a scooter modded with parts to peak power at max RPM - (say 70mph+) is daily driven at 30 to save gas , the pipe will still draw extra mixture into the exhaust at lower RPMs. But at 30, the returning 'boost' peaks, and ebbs in the cylinder well before the piston closes. Thus the extra fuel and air drawn in by the tuned exhaust, and pushed back in the cyl by the return pulse is lost. It's blown back out into the exhaust until the piston closes the port.
mousewheels wrote:We could/should spend some time here looking for contributing factors to poor economy. One thing to look at are production larger two stroke scooters. Bear's 80 and 125 cc scooters are no doubt getting better than 30mpg
Here's one idea:
Tuned pipes, when run below their design rpm point are a negative for fuel consumption and emissions. Timing between the vacuum and return pulse are mechanically fixed to the optimum RPM for which the pipe is designed. When a scooter modded with parts to peak power at max RPM - (say 70mph+) is daily driven at 30 to save gas , the pipe will still draw extra mixture into the exhaust at lower RPMs. But at 30, the returning 'boost' peaks, and ebbs in the cylinder well before the piston closes. Thus the extra fuel and air drawn in by the tuned exhaust, and pushed back in the cyl by the return pulse is lost. It's blown back out into the exhaust until the piston closes the port.
It could be my exhaust, that is a good tip.
Im running a leovince ZX. I have heard alot of good/bad about it.
It runs great when it was on my 50cc cyl, but now that its on the 70cc I dont know the difference. I dont have any other pipes. And I dont want to fork out 200$ for a new pipe.
'98 Yamaha Jog Cy50k
'96 "Frankenstein" Japanese Jog Cy50
30mpg is roughly what my Jog was getting with similar set up but with the stock carburetor 44 pilot, 115 main during break in. Provoscooter.com has some good parts.
Gingerbread Man wrote:30mpg is roughly what my Jog was getting with similar set up but with the stock carburetor 44 pilot, 115 main during break in. Provoscooter.com has some good parts.
Yeah I plan on buying my tuning springs and stuff from provo.
After break in what did you switch to?
'98 Yamaha Jog Cy50k
'96 "Frankenstein" Japanese Jog Cy50
I never had the chance to fine tune it. I took the 70 kit off and and sold the Jog. I plan on putting the 70 on my Zuma though eventually. I'll be watching to see how your tuning turns out.
Gingerbread Man wrote:I never had the chance to fine tune it. I took the 70 kit off and and sold the Jog. I plan on putting the 70 on my Zuma though eventually. I'll be watching to see how your tuning turns out.
Oh alright
My goals are to hit atleast 70mph.
I want it to be quick in acceleration without losing any mid/top end.
MPG is my sacrifice right now. I do have a 28mm koso carb with powerjet for when I want to really mess with it
'98 Yamaha Jog Cy50k
'96 "Frankenstein" Japanese Jog Cy50
DaylightDies wrote: My goals are to hit atleast 70mph.
I want it to be quick in acceleration without losing any mid/top end.
MPG is my sacrifice right now. I do have a 28mm koso carb with powerjet for when I want to really mess with it
Unless you have the kind of power a Top Fuel Dragster has or a Funny Car, you will always sacrifice acceleration of top speed or vise-a-verse-a. You can't have everything.
Bear 45/70
'83 Aero 80 X 3
'84 Aero 80 X 3 '85 Aero 80 '84 Aero 125 X 2
'84 Aero 125 '84 Aero 125 X 2 '85 Aero 50
'85 Spree
DaylightDies wrote: My goals are to hit atleast 70mph.
I want it to be quick in acceleration without losing any mid/top end.
MPG is my sacrifice right now. I do have a 28mm koso carb with powerjet for when I want to really mess with it
Unless you have the kind of power a Top Fuel Dragster has or a Funny Car, you will always sacrifice acceleration of top speed or vise-a-verse-a. You can't have everything.
Ever ride a Boss Hoss? 2 gears and no problem with acceleration or top speed
But yes, a 12hp scooter is going to give up quickness to achieve more acceleration.
DaylightDies wrote: My goals are to hit atleast 70mph.
I want it to be quick in acceleration without losing any mid/top end.
MPG is my sacrifice right now. I do have a 28mm koso carb with powerjet for when I want to really mess with it
Unless you have the kind of power a Top Fuel Dragster has or a Funny Car, you will always sacrifice acceleration of top speed or vise-a-verse-a. You can't have everything.
I can always try
'98 Yamaha Jog Cy50k
'96 "Frankenstein" Japanese Jog Cy50
, the pipe will still draw extra mixture into the exhaust at lower RPMs. But at 30, the returning 'boost' peaks, and ebbs in the cylinder well before the piston closes. Thus the extra fuel and air drawn in by the tuned exhaust, and pushed back in the cyl by the return pulse is lost. It's blown back out into the exhaust until the piston closes the port.
