intake length and torque

leo

leo

Member
hello all,
sorry guys, i have newb questions again.

i have read that going from the standard intake to a longer offset intake will increase power in the low to mid range.

i just got a 44t on my bike, had to bend the forks to get it on. anyway, i don't think i want to go any bigger on the rear sprocket because i would probably be giving up too much top end.

i got an expansion chamber on the way, but i wanted to know if changing to a longer offset intake would be an increase worthy of having my pretty new carb hanging outside the frame and making it look lopsided. (not to mention cleaning up all the awefull fabrication work on this offset's mounting surface)

i guess my question is, if i had 2 identical bikes (other than the intakes) on level ground, would the difference in low end power be noticeable or not?
are we talking 1% low end torque improvement, or 50% increase in take off power WHILE keeping the 44t's top end peed?

how does it work?
 
I've found on all my bikes, whether stock or heavily modified, the shorter the intake, the more power all around.
 
ok, im confused.
dave, you made one of the posts that lead me to think a longer offset intake would make more low end torque. (last paragraph, in red)
did i misunderstand?? the shorter intake will favor the low end/take off power??
if so, that's good news. i would rather trim the factory one down a bit and just take the bend out completely. the offset intake i ordered looks like it would need tons of sanding.



05-13-2015, 09:31 AM
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Davezilla Davezilla is offline
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Join Date: Mar 2014
Location: San Antonio Texas
Posts: 2,272
Default Re: carb wont fit in my frame
I got mine to fit by using a shorty intake, then had to trim the stock air filter to get it to fit in there... Here's an older set of pics where I was using a CNS carb with an offset air filter duct, this gave me the clearance I needed but I ended up going back to the stock carb since it worked a lot better...



Here's a pic with the stock carb and I was going to put on one of those K&N type filters but it wouldn't fit, I ended up using a standard NT carb air filter but had to trim a little off the top back corner of the filter housing to get it to fit without touching anything else...



Kinda hard to see since I have no close ups of the stock air filter installed, but you can see where it looks like it's touching the top frame tube... there's only about 1/16" clearance if even that, and I had to do some trimming to get it in there... You can see the short intake manifold pretty well tho, this is the only way I had clearance to put the carb inside the frame...



You can try a shorty intake if you would rather keep the carb inside the frame, or you can go with an offset intake which also works. Personally I don't like the offset intakes even tho they are really good for adding momre torque to the engine's output, they do restrict the max rpm to under 6000.
 
The quick answer there is Yes... the offset intakes do make lots of torque, but they also fall flat somewhere between 5000 and 6000 rpm depending on how you got the engine set up...
What I've found out tho is you can still get torque like that with the small straight shorty intakes and not lose as much top end power and rpm... so yes, they work and make lots of torque, but at too much of a cost of top end power and rpm.

You can get similar torque with the shorty intakes, but not by themselves... with porting, higher compression, and a pipe that matches the engines power curve. With an offset intake installed tho, all the porting in the world won't let it rev to a decent rpm.. or even a stock like rpm. It's just too restrictive.
 
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