Port intake on bicycle engine

S

sisdavid

New Member
I ported my intake, do not know if it will gain any performance, but that lip on the intake always aggravated me. so while I had the intake off replaceing the gasket I ported the intake, I did not cut into the metal deep just enough to get that lip off, and then slanted the rest to match the size of the engine intake hole, but not quite a lot removed the scuffing of the face of the intake manifold is so the RTV has something to hold on too, I was afraid that RTV was going to squish out, but it pretty much stayed put, anyone else ever mess with this RTV stuff? Can't wait for 24 hours to be up so I can test it out that is how long RTV dry.

YouTube - motorized bicycle
 
Re: Port intake

RTV, when applied correctly works great, you already know the key-use a thin layer and let it sit overnight.
 
Re: Port intake

High temp RTV in my oppinion is best. Lock tite too, also if you grab a bolt with pliers and mess up the threads a little it will help keep it from viberating off.
 
Re: Port intake

Okay, last night I opened the bike up for a prolonged period of time on A1A , Daytona Beach, motor bikers dream come true, and grinding that lip off of the intake did make a noticable improvement on the engine. Lot more torque too.
 
Re: Port intake

Did you match port the exaust pipe too?
In my opinion, it's more important for top end speed than the intake.
It's way more important to make the ports in the manifolds MATCH the ports in the cylinder, not just open up the manifolds! This way the air flows smooth & faster... (^)
 
Re: Port intake

long time working on cars heres what u use on intake and all gaskets no more leaking period! high-temp red rtv silicone [gasket maker] Ive patched sub woofers when the foam rings blew out. this stuf has perfect headers on hot rods for years my moter has no leaks at all. I even put a perfect dab around the primer button on the carb, can still use the button I have picts coming by this weakend. thers a black version as well but not for high heat remmember [gasket maker] permatex
 
Re: Port intake

I have matched both intake and exhaust manifolds to match the ports. First I made a new gasket that perfectly matched the ports on the head. Then I used the gasket as a template to start grinding the intake and exhaust manifolds to match. Makes a big difference. I also got rid of any leftover welding that may be blocking the intake manifold where it makes its bend.
 

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Re: Port intake

I did my exhaust port today. I couldnt believe how "off" it was. I mean the gasket and pipe covered at least 20% of the port on the head. Tomorrow its onto the intake....
 
Re: Port intake

That is what I am saying. It is restricting. All you have to do is your exaust and intake manifold. I could have cut so much off that it would have broke in half, but stoped when I felt structural integrity may be a problem. Do not even have to monkey around with the head. Shoot if you just grinded off the crummy weld stuff you would have done something. Ya, I need to get around to my exuast. Did you notice any difference?
 
Re: Port intake

i too have matched all the ports etc,made a big difference. but i do run a tuned pipe and chamber aswell
 
Re: Port intake

Yes it seems to run smoother thru the powerband. I want to try running it without boost bottle next, I pinched it off and made quite a difference.
 
Re: Port intake

Bike, ported the exaust today, when I took the muffler off I noticed a chunk of weld right there where the exaust exits the very end. Probably restricting 5 to 10% where it finaly exits, my dremmel wheel was a perfect fit. I was so excited that I almost tried to ride it without my High temp Copper RTV being dry have to wait 24 hours. I do not know if the RTV I used is so great, the packeage says do not use on gasoline areas, I think the stuff on my intake is starting to shoot out the sides.
 
Re: Port intake

Hey guys made It a 150 miles no leak on head. I was wrong on underestimating this china eng. considering better studs longer with jam nuts. any input? also have come to the conclusion its better to keep these motors at proper tork spec soes not to distort the cylinder walls. You guys are dead on about your check up ref! on everything so far.
 
Re: Port intake

What about stud thing again. What happen. Take back what I said about orange RTV, probably will work.
 
Where can you find metric threaded rod? My hardware store carries a wide variety of metric nuts and bolts, but not all threaded rod.

Andy-
 
Ahhh, how could I forget McMaster-Carr

I love that 300mm cost more then 1m.

Overall Length Each
30 mm 98833A250 $7.48
40 mm 98833A255 7.76
50 mm 98833A260 8.03
300 mm 98861A525 22.42
1 m 98861A320 13.36
 
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