Offset intake manifold debate

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RollingStones

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I recently purchased a CNS carb but had to still with the stock carb due to the fact that the airfilter hit the frame making it impossible to accurately mount it on to the intake.

I am am looking at offset intake manifolds online but have heard really mixed reviews about them.

Has anyone had a bad experience purchasing them?

If you've purchased one yourself to use with the CNS car by could you send me a link to the site you got yours from?

Curious to hear what you guys think
 
Offset Intake

Had to buy one myself. My first build and the power king motor fit perfectly but the throttle cable was too close to the upper post. Ordered one from boys go fast. Wow was I disappointed. It is literally a peace of scrap metal. So you could say I tossed that money in the toilet. :cry: On the upside to the problem I worked as a metal fabricator and welder for quite a few years so I guess I'll fabricate one myself. Even though it involves a lot of work its better then throwing more money away. :cool:
 
The offset intake from JNMotors is good.
You can even extend the intake even longer for a low RPM power boost. (click on my signature link to read more)
 
What do you think guys? I already run an ADA Juice Box " boost bottle" do you think extending the the intake tract would help my low rpm torque? I can do it very easily by adding another heat spacer in between the head and juice box. In my experience with goped motors I remember that tall manifolds increase high rpm power? But without my juice box it is a dog off the line.

Any thoughts? I'm very over geared or under powered for slow speed cruising. The hills here almost bring me to a stop, the new expansion pipe has helped a lot with high rpm power and if I get it revving it will pull most hills but slows significantly before cresting the hill.
 
A boost bottle is a complete waste of time - it's a subject that's been worked to death.

A reed valve intake is the the best method for improving low and midrange torque, with a side benefit of significantly reducing intake noise.
The heat isolation spacer is an absolutely essential item, but it should not be mounted in between the reed valve and the cylinder. This simply adds to crankcase volume which is exactly what you are trying to avoid.
 
I'd let you try my g43l without the juice box and see the torque fall to almost nothing. The ADA juice box does work! Its not just a bottle tapped into the intake. Its a measured volume of space tuned for my specific engine size. Juice box

Fabian, if you knew how much a reed would be for my motor you may not have suggested that. G43L Reed. I could almost get another engine for that, id then build a 2wd that would pull the hills ;)

I've built reeded G43's and wasn't impressed with the loss of top end and only minor low/mid power increase.

I'm making probably 4+ HP at 12,000 rpm with a ported, piped and upgraded 15mm carb on my g43. I think I just need to re-gear, and loose some top speed but increase my climbing ability.
 
The Chinese 2-stroke centre mount bicycle engines are a completely different thing to a G43L. The two engines cannot be compared.

Forget even the concept of revving a Chinese 2-stroke centre mount bicycle engine to 12,000 rpm, because they have greatly reduced life expectancy after 5,000 rpm, and for good reliability it pays to keep the rpm under 4,500.
Typically i operate the engine in to 3,500 - 3,800 rpm zone, and the reed valve intake makes a noticeable improvement to low and midrange torque with these engines; so long as the jetting is calibrated to suit the new intake system.

I need to add that you have "ZERO" chance of making a Chinese 2-stroke engine punch out 4 horsepower and still maintain rock solid reliability; in fact, you won't even be making 2 horsepower; my engine makes even less than that, but it has strong low and midrange torque; making for a relaxed ride when sticking the bike in top gear and staying there.
 
I need to make a flyby video of my bike at WOT and probably 45mph. This engine sings at high RPM with this small pipe on it. Intake noise is nearly nonexistent, even at speed. But its probably just the pipe drowning the noise out.
 
Like all of these things, it's horses for courses, because the engine would not last very long spinning 12,0000 rpm at WOT; going 45 mph. I concede that it will get you down to the corner shop, but if you need long distance reliability, 12,000 rpm at WOT; hour after hour after hour isn't going to allow that to happen.

If a days riding involves 8 or 9 hours in the saddle, you need a different level of engine operation to fulfill that requirement.
 
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