looking to upgrade my intake manifold from one screw hole to the other reads 4cm so what mm do i need or do i even read from screw hole to screw hole and what would be a cheap good one to use to better my performance and speed i have a stock one
searching for upgrade
- Thread starter Shannon
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FurryOnTheInside
In Memoriam
You can use a piece of fibre reinforced heater hose (the thick walled stuff) and a bit of copper tube with the stock intake manifold (or half of the stock intake manifold with a cheap 40mm spaced offset intake) to make the intake tract up to 7" or so in total.
(total: when measured from the front face of the carb slide to the rearward face of the piston).
I went all out and made mine about 7.5" in total, and put the carb at the left side of the seat tube and slightly angled back inward so the air filter could be tucked in behind the seat tube, and so that the choke lever would be in front of the seat tube.
But I used the final 45° bend that I cut off the stock intake, and used a piece of hose with a 45° bend in it which costs a few £ more, then half of the cheap offset intake upside down.
I got my offset intake from chineseBay because I have the 32mm bolt spacing. The hose and clamps came from fleaBay too.
(total: when measured from the front face of the carb slide to the rearward face of the piston).
I went all out and made mine about 7.5" in total, and put the carb at the left side of the seat tube and slightly angled back inward so the air filter could be tucked in behind the seat tube, and so that the choke lever would be in front of the seat tube.
But I used the final 45° bend that I cut off the stock intake, and used a piece of hose with a 45° bend in it which costs a few £ more, then half of the cheap offset intake upside down.
I got my offset intake from chineseBay because I have the 32mm bolt spacing. The hose and clamps came from fleaBay too.
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6blueoval9
Well-Known Member
You're not really going to find a "better" intake manifold so to speak.
The aluminum intake you have can be opened up to accept a larger carburetor if that's what you want to do.
You can use one of the chromed steel intake manifolds that are bigger in diameter but really without a bigger carburetor won't make much of a difference if any to your performance...a longer intake tube would benefit low end torque with a speed loss while a shorter one would benefit top end speed with a loss of torque.
I would personally get the 16mm NT "speed" carburetor (performance version of your stock carburetor) ($20 or so) and hone/bore out the stock intake inlet to 16mm for improved performance everywhere in the power band using your stock aluminum intake manifold.
You should a little more low end, with more mid range and top end taking this route.
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Sounds good how to bore out the stock intake inlet and can it be used on the street I'm in Wichita ks and laws state I can ride a bike as long as it doesn't go above 30 which is fine for me but I want to up top speed even if just by 5 mph so my engine won't struggle ad much to hit top speed you know how a stock car and go 160 but is slow to get that speed after 120 I want to have more speed to have fun with but at same time when I ride it to work not struggle to get to the speed so any mods a can get away with list them
6blueoval9
Well-Known Member
I'm in the same area just outside of Maize.
The intake will still be legal...I suppose as long as you don't caught with a radar your fine with anything you put on the bike...the speed will get the ticket, not the parts on it.
I'm not sure you'll gain 5 mph from just that change but it will help.
What size sprocket are you using?
6blueoval9
Well-Known Member
You may want to see if it has any marking on it that will tell you.
If you have a stock motor with say a 36t or even a 38t sprocket it wont accelerate all that well especially from the start and can hurt top speed if the motor doesn't have enough rpms or torque.
If you have a stock motor with say a 36t or even a 38t sprocket it wont accelerate all that well especially from the start and can hurt top speed if the motor doesn't have enough rpms or torque.
