Custom Intake Fabricated - Carb Relocation - PIX

[gy6rocket]

Well Its been cold and snowy here so the winter tear down has commenced! There are quite a few mods I have planned for this scooter during the down time ::sinister laugh::

First order of business is a new intake. Ever since I starting digging into this scooter I've hated the way the engine mount is. It's basically 'tangled' into the carb and airbox setup. I have elected to construct a new lightweight aluminum mounting system with poly bushings for the gy6. My first step is to get the carb out of the way. This mod allows very easy access to the carb and it's adjustments. I can actually change the jets without removing the carb now! It also leaves me some space for a nice strong aluminum mount. I accomplished this by using a 26mm aluminum intake and a custom piece of 1.25" mandrel bent tubing along with 2 mating collars and 4 heavy duty hose clamps. I turned the intake 180 degress from stock and positioned the carb so that it faces forward and is straight and level when the bike is loaded. The ease of carb access is just a perk... my real reason to do this is so I have a forward mounted intake, aka RAM AIR style! A ram air collector is in the planning stage in order to force feed the gy6 at high speed.

Anyway everything came out good, Had to extend the gas line a bit and relocated the on/off switch right at the carb fuel intake. Threw the UNI on there for now until I devise the ram air cowl.

I also painted my CVT cover with an industrial wrinkle finish to match the head. I love the wrinkle texture and its extremely strong and resists dirt, oil, and crud. The paint takes about 3-4 days to fully cure. Mine is still drying, as you can see there are no screws re-installed yet.

I'm also converting to a mono shock in the back... Just going to but 1 really good nitrogen shock and run it on the left side. Less weight and I like how the suspension moves with the mono shock.

I will most likely be getting rid of my exhaust can for something much smaller and lighter so I don't need the can straps. I will keep the 1" header though

Stripped more steel parts, for the fender and mounting brackets.

Anyway here are some pics, BET 'CA NEVER SEEN THIS BEFORE!





LEFT SIDE



TOP



CVT COVER

[scootdoggydog]

howcome i can see the clutch through the cvt cover?

[gy6rocket]

Another mod for endurance clutch performance, the bell does not even heat up now.

[2btiger]

Brilliant work gy6rocket, people talk about it but you've been about it . Bone for sharing. I've got to get the info on that paint, I love that look too. Let us know how well it cures 'n' stuff.

[mx5tc]

Hot damn! About time someone put the carb on the right way! The stock location forces the intake mixture to make a violent 180 turn after leaving the carb. The front mounting now provides a nice smooth inlet path. I'm inclined to believe that power is going to be improved with this setup. You may even be able to jet down 1 size on the main, the atomized fuel mixture is not be going to have as mainly chances to separate and "puddle" with the smoother intake tract downstream from the carb outlet.

[therustyaxe]

Holly S*@T! NICE!

Rocket and MX are the best guys to watch here for mods or ask for advice.

Way to go Rocket!

[trigger]

Very old school on the CVT cover, bad to the bone! Exposed clutch is just barks power!

[gy6rocket]

I really wanted to keep the CVT cover as complete as possible since I believe it adds a lot of strength to the swing arm. I've seen guys cut the cover in half, although I think this removes strength. With the bell mod, the cover keeps 98% of the strength with the benefits of cooling the clutch down at all speeds. Thanks for the kind words guys! Stay tuned, more tuning to come

[jake318]

GY6 ....IMPRESSIVE If I didnt just install a oil cooler in that area I would be copying you . Do you have a motorcycle junk yard in your area? You could gab a used downdraft carb giving strait shots of fuel to the valves . Jake

[earlwb]

Nice job, very creative.

I have considered using a Weber downdraft carb on my GY6 engine scooter. Weber makes a 28mm version. Commonly seen on the old 4 cylinder Volkswagon engines, etc. Fabricating a intake manifold shouldn't be all that difficult.

[90GTVert]

Nicely done. +1 Bone

[schoei1]

Wonderful idea and great job!!

I am looking forward to this winter, to see all the mods you create.


A bone for you and keep the mods coming.

[randy]

Nice job! Have you ridden it yet? i would be curious as how moving the carb further from the motor affected the power curve? i know from playing with carbed v8 motors the further you moved the carb from the motor {either spacer plates or high rise intakes} the higher in the rpm band the peak H.P. and torque occurs.

[mx5tc]

Nov 28, 2008 7:17:22 GMT -5 randy said:

Nice job! Have you ridden it yet? i would be curious as how moving the carb further from the motor affected the power curve? i know from playing with carbed v8 motors the further you moved the carb from the motor {either spacer plates or high rise intakes} the higher in the rpm band the peak H.P. and torque occurs.

Randy,

You've got this a little mixed up. An intake runner is tuned by both length and diameter. A long intake runner with moderately sized ports is good for low end and midrange torque. Look at the old Mopar Max Wedge Cross Ram Dual 4bbl manifolds or at the stock manifold on a 5.0L HO Ford...long runner designs add low and mid range torque.

A short runner intake (hi-rise 4bbl) gives up low and midrange torque to maximize top end horsepower. Check the runner lengths of any modern EFI V8 (GM LSX, Ford Mod Motor, Chrysler Hemi) and you'll see they are much longer than the old single 4bbl intakes of the 60's and 70s. Note that the classic Pro Stock tunnel ram manifold with dual quads is really a long runner intake with very large diameter ports.

[gy6rocket]

I have not ridden it yet, but I did fire it up and ran her for a few minutes to make sure everything was in tune. All I gotta say is WOW! It has a much deeper, throaty intake sound now, I'm sure this has to do with both the intake manifold and the lack of tubing coming off the inlet of the carb, just a UNI there now. Throttle response seems to have improved also, I just touched the throttle and it wanted to jump off the side stand. All in all very happy so far, I will get some video of it running and hopefully get some decent weather so I can toss the seat on and give it a ruckus style run

[gy6rocket]

Here is a little diagram I drew up of the differences in the intake modification. There are two advantages. 1 is a cleaner smoother intake path, less turbulence. 2 is the reasoning that when the bike is in motion, it will be pushing air into the front of the carb forming a ram air situation causing (hopefully) a positive pressure in the intake. When the manifold pressure is greater then the atmosphere this is usually referred to as boost, meaning the intake stroke will not have to "suck" the gas into the combustion chamber, it will literally be blown into the combustion chamber when the intake valve opens. More gas and air to squeeze = more power.

[tribune2005]

gy6rocket I have a question for you. After your mod will you plastics fit back on? Looks like the air filter sticks out to far. Will you have to modify your plastic?

[fastasssr20]

I think he runs with that vent off in the front anyway so it shouldn't be a problem.

[gy6rocket]

Correct, I have not run that front panel in quite some time. I like air to flow through the engine bay over the head and voltage regulator. Gives it a nice hardcore look I dremeled the mounting tabs off so it looks like its supposed to be open.

So the next mod is going to be good tires and repainted wheels

WHAT COLOR SHOULD I PAINT THE WHEELS?? I was thinking neon green -- the final gloss black paint and clear coat are going on the panels.

[mx5tc]

OMG, Neon green??? WTF! Ever see any Gemini, Apollo or Space Shuttle craft in neon green?? I don't think so! Paint the wheels neon puke green = GY6 TOILET!

Puuuuuuuuuuulease show your scoot the respect it is due and put a color worthy of the name "Rocket" on its wheels!

[gy6rocket]

Hehe,

yeah - it was just a thought, it probably would look like puke, but this leaves the question open ended, what color? gloss white, bright red, baby blue? I want something bold!!

[scootdoggydog]

black or chrome or silver or gray

[phaze]

im in with red very old school.
but im puzzled why you would weaken the rear suspension with a solo shock? i thought you were all about stiffness?

[mx5tc]

Red & black combo

[gstraitman]

ramjet technology, nice

[gy6rocket]

Nov 30, 2008 9:52:07 GMT -5 phaze said:

im in with red very old school.
but im puzzled why you would weaken the rear suspension with a solo shock? i thought you were all about stiffness?

I'm thinking red would look pretty cool!

I am designing my own mount for the front with stiffer bushings to tighten that up from left to right. After testing the suspension out with the monoshock, it still seems very stiff, although dampening and shock absorbing seem better. I don't ride two up and am still looking for items to strip weight, and that second shock saved me a few lbs. Plus the shock(s) I want are billet aluminum, strong and $$$!!!

[phaze]

cool i hope it pays out buddy. atleast your willing to take chances lol

[Aerostudent]

Hmmm... I am in the process of getting a carb that rocket would be envious of (28mm-slide, keihin) and may just steal this idea and do bot hat the same time. ;D I wanted to do this to my mom's 86 elite, but...

Dude, sweet mods and nice pics with write-up! + 1 for you!

Aero

[shookupart]

okay. man. WOW. this is revolutionary. I am beyond impressed and I am absolutely going to mount my new 32mm manual choke keihin in the same way. TOO BITCHIN' DUDE!!!! freakin radical. Im stoked. Ive been tryin' to find out where this actual thread was. jrinnlv gave me the lead and HERE IT IS!!! killler. good work and I am fabricating a mod brace to stiffen the frame up as well so if anyone has any more pics about that I would like to see them too. gy6 rocket: I have been tryin to pm you. twice now. Im not a scooter psycho( I am ) I just need a lil more details. please help a brother out. thanks and what an amazing project

[pac1982]

In theory this is a very good idea but i think the fact that the nose cone of your scooter and your legs are going to be in the way of the air flow you will see no real gain in power to get the most out of this mod you would either need to locate the filter so its in direct contact with the air flow or create some kind of ducts to guide the air to your filter.

I get the point that it no longer has to make a u bend but on such a small engine I can’t see it making much difference, if your tests prove me wrong let me know as I really like the concept I just cant see it doing anything