Felt Twin 4 stroke build

GoldenMotor.com

SD moto man

New Member
Aug 27, 2011
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San Diego
I installed the 56T today I got from Pirate cycles. I noticed a pretty big improvement in torque off the line from my 48T. Still not quite as good as my old 2 stroke, but good enough to live with.

I have my eye on AGK's bored carb and air filter...
 

SD moto man

New Member
Aug 27, 2011
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San Diego
I noticed a pretty big difference on the top end as well, probably 5 mpg less now. It goes about 30 on the flat, which is fine with me, that's fast enough. I like the acceleration more than the top end and also live in a pretty hilly area so it's much better on the steeper streets.
 

Dbogue

New Member
Mar 7, 2012
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Escondido
I just installed my qmatic and 56t today and I must say I'm sorely disappointed.. With my wet chain drive and 40t I could give it a little shove (no pedaling) to get going and be cruising at 27-28 in no time. The qmatic takes forever to get up to speed (with pedaling) and I barely get over 30 on the flats. Is there a break-in period for the ezm tranny or is this what you are experiencing as well? I must say the clutch engagement is very smooth but that's hardly consolation for losing all low-end power. Hills? Fuhgettaboutit. Please tell me it gets better.
 

The_Aleman

Active Member
Jul 31, 2008
2,653
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el People's Republik de Kalifornistan
I noticed a pretty big difference on the top end as well, probably 5 mpg less now. It goes about 30 on the flat, which is fine with me, that's fast enough. I like the acceleration more than the top end and also live in a pretty hilly area so it's much better on the steeper streets.
That's good to hear, glad you got it sorted out. Yeah, the 49cc 4-strokes aren't gonna compete with the HTs in overall horsepower output, and the Q-matic has a real soft touch on the drivetrain, which makes it a little sluggish off the line. That also makes it pretty nice to your bicycle frame compared to most other drivetrains.

My lil brother bought one of the first Q-matics and I put over 200 miles on it myself. Compared to my 4G, it's really gentle! A 4G hits the drivetrain much harder, especially with a shift kit and sloppy throttle actuation. Of course, that also makes a 4G quite a bit quicker off the line.

As for your current speeds, sounds like you have a bottleneck somewhere. These 49cc engines come with small carb jets, restrictive exhaust, a low(ish) compression ratio, and the valves are often out of adjustment. Adjust your valves first, engine cold, and then figure out whather you need to enlargen the carb jet or not. You prolly will.


I just installed my qmatic and 56t today and I must say I'm sorely disappointed.. With my wet chain drive and 40t I could give it a little shove (no pedaling) to get going and be cruising at 27-28 in no time. The qmatic takes forever to get up to speed (with pedaling) and I barely get over 30 on the flats. Is there a break-in period for the ezm tranny or is this what you are experiencing as well? I must say the clutch engagement is very smooth but that's hardly consolation for losing all low-end power. Hills? Fuhgettaboutit. Please tell me it gets better.
Read what I wrote above, it may be informative. The 56T is the highest recommended gear for the Q-matic. Lower gears (larger rear sprocket) is often what is needed for better take off with em. Larger sprockets don't affect top speed as much on the Q as say, the HT. They aint cheap tho! Or, you could push off the line a little harder and pedal some more hehe. Well, these are sposed to be motor-assisted anyway :D

If your engine is running top notch, you'll get the best out of your setup. Adjust the valves, run a decent quality multi-viscosity oil, get the right jet for your setup. These engines make max horsepower about 7K, but their redline is ~8K, 9K+ if they are built right and run good oil - these engines don't get enough at high rpm.

Off the line tho, you need to refine your riding style or get more cubic inches lol :D 49 can only do so much! Legs can be big torque.
 

MotorBicycleRacing

Well-Known Member
Jul 28, 2010
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I just installed my qmatic and 56t today and I must say I'm sorely disappointed.. With my wet chain drive and 40t I could give it a little shove (no pedaling) to get going and be cruising at 27-28 in no time. The qmatic takes forever to get up to speed (with pedaling) and I barely get over 30 on the flats. Is there a break-in period for the ezm tranny or is this what you are experiencing as well? I must say the clutch engagement is very smooth but that's hardly consolation for losing all low-end power. Hills? Fuhgettaboutit. Please tell me it gets better.
What motor? Huasheng 50 cc?
What wet chain drive were you using with a 5/8" shaft Huasheng?
Do you know what ratio or sprocket sizes?

What exhaust are you using?

Your 56t gearing is set to run 42 mph at 7800 rpm
 

scotto-

Custom 4-Stroke Bike Builder
Jun 3, 2010
6,505
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Ridin' inSane Diego, CA.
I don't see anything here making me want a 4 stroke.
Ya know, I would have thought the same thing 20 years or so ago. I look at Nashmoto's 4-stroke (and raced against it) and I look at your Atomic BB 2-stroke which are both built on the same bicycle (I own one as well) and I know which one I would rather ride or race. But that is just my opinion and it's not based on just looks alone.......performance speaks for itself.

Give me the 4-stroke please (^)
 
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Dbogue

New Member
Mar 7, 2012
31
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Escondido
Ya I think more cc's might be in my future.. I need more PPOOOWWWAAAAA. Unfortunately, I have to stop, go up slight inclines, and turn in my daily commute, so the huasheng 56t qmatic combo doesn't have enough torque. I might have a friend coming in to town from AZ though =} hellloooooo 99cc

I was running the tapered shaft HS with the wet chain gearbox from bike berry with a 40t rear, phantom exhaust. I liked the ability to just push off (not pedaling) and be scooting along pretty quickly but I wanted to be able to keep up with traffic (not be in the way) if I needed to also. The setup just didn't have enough top end to do that so I went for a qmatic. Now I have the opposite problem. So I think I'll keep the top end and just give the q more hp to work with.

Edit: my first non-newbie post! :)
 
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Dbogue

New Member
Mar 7, 2012
31
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0
Escondido
Ok. I went 39mph on my bicycle today. Having little torque to speak of still sucks, but I must confess that a smile crept onto my face as I got sideward glances from the drivers of the cars I passed. Touché, EZM, touché.
 

jliveit

New Member
Sep 10, 2012
34
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California
I know this might sound like a dumb question but what is that motor and tranny set up on your bike. Is it only 50cc? Because it looks like a much larger engine?