GY6 CV Carb Update
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- Wheelman-111
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GY6 CV Carb Update
Greetings:
Advantages:
There are tons of these 24mm carbs on eBay for around $60. Some are Chinese clones, but some are genuine Keihin.
The spigots fit the CT manifolds.
The bystarter connection snaps right in.
A 105 main jet works with the 65cc bore, easily obtained from the Keihin catalog.
It pulls like a freight train.
Fuel mileage is improved over a regular roundslide carb.
Disadvantages:
You need to fab a throttle cable with 4.5" of free pull and a 7mm barrel end.
The 40mm bell mouth needs a filter to fit, won't clear the Aero panel without slicing the priceless plastic.
Jetting at the ragged edge of power production for 65cc is touchy. A 102 main won't allow WOT for long, but a 105 is a bit rich in the midrange.
There's no help but my experience breaking this new ground, and setups vary.
Advantages:
There are tons of these 24mm carbs on eBay for around $60. Some are Chinese clones, but some are genuine Keihin.
The spigots fit the CT manifolds.
The bystarter connection snaps right in.
A 105 main jet works with the 65cc bore, easily obtained from the Keihin catalog.
It pulls like a freight train.
Fuel mileage is improved over a regular roundslide carb.
Disadvantages:
You need to fab a throttle cable with 4.5" of free pull and a 7mm barrel end.
The 40mm bell mouth needs a filter to fit, won't clear the Aero panel without slicing the priceless plastic.
Jetting at the ragged edge of power production for 65cc is touchy. A 102 main won't allow WOT for long, but a 105 is a bit rich in the midrange.
There's no help but my experience breaking this new ground, and setups vary.
Wheelman-111
Most of my money is spent on scooterparts. The rest is just wasted.
"ISO": '03 Vespa ET4 Malossi187 74MPH
Flash 9: 2001 Elite SR Contesta 72 ZX Tran, 9:1 Gears, Stock Airbox/Carb/Pipe 58.8 MPH
Punkin: 2010 Vespa/Malossi S78, 61MPH
Most of my money is spent on scooterparts. The rest is just wasted.
"ISO": '03 Vespa ET4 Malossi187 74MPH
Flash 9: 2001 Elite SR Contesta 72 ZX Tran, 9:1 Gears, Stock Airbox/Carb/Pipe 58.8 MPH
Punkin: 2010 Vespa/Malossi S78, 61MPH
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- CBR1000RR
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Re: GY6 CV Carb Update
Have you considered some sort of angled filter setup? Or is the carb too big?
I am not a mechanic, nor do I play one on TV. Actually my advice is probably worth slightly less than what you pay to view it.
- Wheelman-111
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- Posts: 11325
- Joined: Wed Oct 22, 2008 5:09 pm
- Location: Deepinnaharta, Texas
Sliced Plastics
Greetings:
The. CT manifold puts any carb outside the plastic perimeter. My Arreche "Octopus" fiter squeezed on - barely - with plenty of KY jelly and a firm clamp.
Yes, sadly had to slice into precious Aero plastic, but the upside is that panel removal is no longer necessary for carb adjustment or removal.
Now with ported Malossi 65 bore and ample carburetion, it just rips to 55 and beyond but temps get uncomfortably high with #102 supplied. Jetting awaited to see how far. Honda CL 125 jet is 105, and 107.5 is listed in Keihin catalog. One of those should be ideal.
The. CT manifold puts any carb outside the plastic perimeter. My Arreche "Octopus" fiter squeezed on - barely - with plenty of KY jelly and a firm clamp.
Yes, sadly had to slice into precious Aero plastic, but the upside is that panel removal is no longer necessary for carb adjustment or removal.
Now with ported Malossi 65 bore and ample carburetion, it just rips to 55 and beyond but temps get uncomfortably high with #102 supplied. Jetting awaited to see how far. Honda CL 125 jet is 105, and 107.5 is listed in Keihin catalog. One of those should be ideal.
Wheelman-111
Most of my money is spent on scooterparts. The rest is just wasted.
"ISO": '03 Vespa ET4 Malossi187 74MPH
Flash 9: 2001 Elite SR Contesta 72 ZX Tran, 9:1 Gears, Stock Airbox/Carb/Pipe 58.8 MPH
Punkin: 2010 Vespa/Malossi S78, 61MPH
Most of my money is spent on scooterparts. The rest is just wasted.
"ISO": '03 Vespa ET4 Malossi187 74MPH
Flash 9: 2001 Elite SR Contesta 72 ZX Tran, 9:1 Gears, Stock Airbox/Carb/Pipe 58.8 MPH
Punkin: 2010 Vespa/Malossi S78, 61MPH
- Wheelman-111
- Moderator
- Posts: 11325
- Joined: Wed Oct 22, 2008 5:09 pm
- Location: Deepinnaharta, Texas
Carb Primer
Greetings:
I found this somehow, somewhere - stashed in old Favorites file.
http://www.drpiston.com/Cvcarbs.html
Despite making a wildly inaccurate statement in the third paragraph - water is a non-compressible fluid and does not "loosen up" like a gas when flowing - the explanations are pretty easy to follow and likely correct.
Still not a schematic of my VE24, but gives a general idea of CV carbs' function.
I found this somehow, somewhere - stashed in old Favorites file.
http://www.drpiston.com/Cvcarbs.html
Despite making a wildly inaccurate statement in the third paragraph - water is a non-compressible fluid and does not "loosen up" like a gas when flowing - the explanations are pretty easy to follow and likely correct.
Still not a schematic of my VE24, but gives a general idea of CV carbs' function.
Last edited by Wheelman-111 on Wed Jun 10, 2009 3:28 pm, edited 1 time in total.
Wheelman-111
Most of my money is spent on scooterparts. The rest is just wasted.
"ISO": '03 Vespa ET4 Malossi187 74MPH
Flash 9: 2001 Elite SR Contesta 72 ZX Tran, 9:1 Gears, Stock Airbox/Carb/Pipe 58.8 MPH
Punkin: 2010 Vespa/Malossi S78, 61MPH
Most of my money is spent on scooterparts. The rest is just wasted.
"ISO": '03 Vespa ET4 Malossi187 74MPH
Flash 9: 2001 Elite SR Contesta 72 ZX Tran, 9:1 Gears, Stock Airbox/Carb/Pipe 58.8 MPH
Punkin: 2010 Vespa/Malossi S78, 61MPH
- bradthreee
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- Joined: Tue Sep 12, 2006 4:20 pm
- Location: MARS...
Re: GY6 CV Carb Update
I meant to ask before is that a Dio kicker front half on your Aero motor?
- Wheelman-111
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- Posts: 11325
- Joined: Wed Oct 22, 2008 5:09 pm
- Location: Deepinnaharta, Texas
Re: GY6 CV Carb Update
Greetings:
Curious Cubed axt:
Yea, verily my engine's a righteous AF-05/SE50, which you could see clearly on my tranny case were it not for legendary (bad) Wheelman photography skills. That don't stop it from blowing on by 60 on 65cc.
My goals: 1 MPH per cubic centimeter. 5 Degrees F. per MPH
I'll keep you posted.
Curious Cubed axt:
No sir-ree BradThreee! Thet-thar's a 1987 SE50M front half case cover from the Japanese Domestic Market DJ-1. Evidently Honda had an infinite variety of combinations and permutations not sold Stateside. Witness the weird half-05/half-16 reed block from the '88-'89 Elites. Neither fish nor fowl, but fits US-model Aero and Elite AF 05E cases just the same. (I like to think of these weird parts as BarraChickens...) This is just one reason why WHAC welcomes all scooters, foreign and domestic, into the orphanage.I meant to ask before is that a Dio kicker front half on your Aero motor?
Yea, verily my engine's a righteous AF-05/SE50, which you could see clearly on my tranny case were it not for legendary (bad) Wheelman photography skills. That don't stop it from blowing on by 60 on 65cc.
My goals: 1 MPH per cubic centimeter. 5 Degrees F. per MPH
I'll keep you posted.
Wheelman-111
Most of my money is spent on scooterparts. The rest is just wasted.
"ISO": '03 Vespa ET4 Malossi187 74MPH
Flash 9: 2001 Elite SR Contesta 72 ZX Tran, 9:1 Gears, Stock Airbox/Carb/Pipe 58.8 MPH
Punkin: 2010 Vespa/Malossi S78, 61MPH
Most of my money is spent on scooterparts. The rest is just wasted.
"ISO": '03 Vespa ET4 Malossi187 74MPH
Flash 9: 2001 Elite SR Contesta 72 ZX Tran, 9:1 Gears, Stock Airbox/Carb/Pipe 58.8 MPH
Punkin: 2010 Vespa/Malossi S78, 61MPH
- bradthreee
- Board Supporter
- Posts: 2142
- Joined: Tue Sep 12, 2006 4:20 pm
- Location: MARS...
Re: GY6 CV Carb Update
I'm thinking of cutting mine in half I really am jocking your style
- Wheelman-111
- Moderator
- Posts: 11325
- Joined: Wed Oct 22, 2008 5:09 pm
- Location: Deepinnaharta, Texas
Re: GY6 CV Carb Update
Greetings:
Half-cover is the way to go. Cooler clutches and that Dioid mystique that excites the girls so. Well, the nerdy ones, anyway...
Sawzall is among Primitive Wheelman Tool Kit.
Half-cover is the way to go. Cooler clutches and that Dioid mystique that excites the girls so. Well, the nerdy ones, anyway...
Sawzall is among Primitive Wheelman Tool Kit.
Wheelman-111
Most of my money is spent on scooterparts. The rest is just wasted.
"ISO": '03 Vespa ET4 Malossi187 74MPH
Flash 9: 2001 Elite SR Contesta 72 ZX Tran, 9:1 Gears, Stock Airbox/Carb/Pipe 58.8 MPH
Punkin: 2010 Vespa/Malossi S78, 61MPH
Most of my money is spent on scooterparts. The rest is just wasted.
"ISO": '03 Vespa ET4 Malossi187 74MPH
Flash 9: 2001 Elite SR Contesta 72 ZX Tran, 9:1 Gears, Stock Airbox/Carb/Pipe 58.8 MPH
Punkin: 2010 Vespa/Malossi S78, 61MPH
Re: GY6 CV Carb Update
WIth those results, I'm not even sad you cut the s*** out of that plastic. Want to rebuild my NB50M for me?
1984 Honda Aero 50
1986 Honda Spree
1986 Honda Spree
- Wheelman-111
- Moderator
- Posts: 11325
- Joined: Wed Oct 22, 2008 5:09 pm
- Location: Deepinnaharta, Texas
Re: GY6 CV Carb Update
Greetings:
Ms sound like they could be tough to modify. I gather they have a different... Uhh.... Everything!
Piston's 40mm, right? So the crank's gotta be uh, carry the 2... Around 40mm also?
Do you know what the drive end diameter of the crank is? Maybe a Keli variator fits? Then you'd just need RPM.
The bore kits're probably all gone, if they ever existed. Two-bolt manifolds limit carb and intake choices to maybe porting out the case inlets and mani pipe, maybe composite reeds. No exhausts either, unless you can weld your headpipe onto a Biturbo for Tomos 50-70 expansion chamber. With some cylinder porting work maybe o-ringing the head and a bigger back tire, I'm just guesssing, but 50 MPH from 50cc is probably feasible.
Ms sound like they could be tough to modify. I gather they have a different... Uhh.... Everything!
Piston's 40mm, right? So the crank's gotta be uh, carry the 2... Around 40mm also?
Do you know what the drive end diameter of the crank is? Maybe a Keli variator fits? Then you'd just need RPM.
The bore kits're probably all gone, if they ever existed. Two-bolt manifolds limit carb and intake choices to maybe porting out the case inlets and mani pipe, maybe composite reeds. No exhausts either, unless you can weld your headpipe onto a Biturbo for Tomos 50-70 expansion chamber. With some cylinder porting work maybe o-ringing the head and a bigger back tire, I'm just guesssing, but 50 MPH from 50cc is probably feasible.
Wheelman-111
Most of my money is spent on scooterparts. The rest is just wasted.
"ISO": '03 Vespa ET4 Malossi187 74MPH
Flash 9: 2001 Elite SR Contesta 72 ZX Tran, 9:1 Gears, Stock Airbox/Carb/Pipe 58.8 MPH
Punkin: 2010 Vespa/Malossi S78, 61MPH
Most of my money is spent on scooterparts. The rest is just wasted.
"ISO": '03 Vespa ET4 Malossi187 74MPH
Flash 9: 2001 Elite SR Contesta 72 ZX Tran, 9:1 Gears, Stock Airbox/Carb/Pipe 58.8 MPH
Punkin: 2010 Vespa/Malossi S78, 61MPH
- Wheelman-111
- Moderator
- Posts: 11325
- Joined: Wed Oct 22, 2008 5:09 pm
- Location: Deepinnaharta, Texas
GY6 Jets: Honda
Greetings:
Honda dealer has to get the Keihin VE jets by the 4-pack, so I've got extries. 105 still runs a bit warm at WOT, ordered 107.5 and 110s if anyone needs 'em. If'n the 110 don't work, I'll have to go Nitrous... I hear that cools yer head pretty good. Especially if you huff it.
Honda dealer has to get the Keihin VE jets by the 4-pack, so I've got extries. 105 still runs a bit warm at WOT, ordered 107.5 and 110s if anyone needs 'em. If'n the 110 don't work, I'll have to go Nitrous... I hear that cools yer head pretty good. Especially if you huff it.
Wheelman-111
Most of my money is spent on scooterparts. The rest is just wasted.
"ISO": '03 Vespa ET4 Malossi187 74MPH
Flash 9: 2001 Elite SR Contesta 72 ZX Tran, 9:1 Gears, Stock Airbox/Carb/Pipe 58.8 MPH
Punkin: 2010 Vespa/Malossi S78, 61MPH
Most of my money is spent on scooterparts. The rest is just wasted.
"ISO": '03 Vespa ET4 Malossi187 74MPH
Flash 9: 2001 Elite SR Contesta 72 ZX Tran, 9:1 Gears, Stock Airbox/Carb/Pipe 58.8 MPH
Punkin: 2010 Vespa/Malossi S78, 61MPH
- Wheelman-111
- Moderator
- Posts: 11325
- Joined: Wed Oct 22, 2008 5:09 pm
- Location: Deepinnaharta, Texas
GY6 CV Up to 110 Main
Greetings:
Installed the 110 main this evening, skipping over the 107.5. I thought I'd need to lower the needle but it ran better in 4th position from richest.
Good Gawd it's faster! Temps finally under control despite mid-90s here in Deepinnaharta. In fact the only time I saw 375 was briefly after shutting off throttle following WOT runs to 55, which arrived alarmingly quickly on my bumpy test road.
I don't want to risk too speed testing at night; can't see the TinyTach except under street lights. It was purring along at 8500 when I could cop a look at 55.
Installed the 110 main this evening, skipping over the 107.5. I thought I'd need to lower the needle but it ran better in 4th position from richest.
Good Gawd it's faster! Temps finally under control despite mid-90s here in Deepinnaharta. In fact the only time I saw 375 was briefly after shutting off throttle following WOT runs to 55, which arrived alarmingly quickly on my bumpy test road.
I don't want to risk too speed testing at night; can't see the TinyTach except under street lights. It was purring along at 8500 when I could cop a look at 55.
Wheelman-111
Most of my money is spent on scooterparts. The rest is just wasted.
"ISO": '03 Vespa ET4 Malossi187 74MPH
Flash 9: 2001 Elite SR Contesta 72 ZX Tran, 9:1 Gears, Stock Airbox/Carb/Pipe 58.8 MPH
Punkin: 2010 Vespa/Malossi S78, 61MPH
Most of my money is spent on scooterparts. The rest is just wasted.
"ISO": '03 Vespa ET4 Malossi187 74MPH
Flash 9: 2001 Elite SR Contesta 72 ZX Tran, 9:1 Gears, Stock Airbox/Carb/Pipe 58.8 MPH
Punkin: 2010 Vespa/Malossi S78, 61MPH
Re: GY6 CV Carb Update
oooh fancy... what's your end goal? The Kessel run in less than twelve parsecs? thanks for the advice on modding my 84... didn't understand a d*** word of it
1984 Honda Aero 50
1986 Honda Spree
1986 Honda Spree
- Wheelman-111
- Moderator
- Posts: 11325
- Joined: Wed Oct 22, 2008 5:09 pm
- Location: Deepinnaharta, Texas
Re: GY6 CV Carb Update
Greetings:
Two-Four, let me know if I can help with your '84. Aerophiliacs need to help one another.
The 110 still flirts with 400 degrees after a minute of WOT, and I'm too chicken to see if its a gauge misread. It holds 50 with ridiculously little throttle. Whack it open at 50 and it just lays down more power and torque, but I won't try it until there's a 115 in the VE24 main channel.
Two-Four, let me know if I can help with your '84. Aerophiliacs need to help one another.
The 110 still flirts with 400 degrees after a minute of WOT, and I'm too chicken to see if its a gauge misread. It holds 50 with ridiculously little throttle. Whack it open at 50 and it just lays down more power and torque, but I won't try it until there's a 115 in the VE24 main channel.
Wheelman-111
Most of my money is spent on scooterparts. The rest is just wasted.
"ISO": '03 Vespa ET4 Malossi187 74MPH
Flash 9: 2001 Elite SR Contesta 72 ZX Tran, 9:1 Gears, Stock Airbox/Carb/Pipe 58.8 MPH
Punkin: 2010 Vespa/Malossi S78, 61MPH
Most of my money is spent on scooterparts. The rest is just wasted.
"ISO": '03 Vespa ET4 Malossi187 74MPH
Flash 9: 2001 Elite SR Contesta 72 ZX Tran, 9:1 Gears, Stock Airbox/Carb/Pipe 58.8 MPH
Punkin: 2010 Vespa/Malossi S78, 61MPH
Re: GY6 CV Carb Update
sounds like your making good power.