VMAX Downdraft Carb conversion

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BLIGHT
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Re: VMAX Downdraft Carb conversion

#46

Post by BLIGHT »

82aspy wrote:
BLIGHT wrote:
Twostick wrote:Love the bike!

What kind of mufflers are those?

Kevin
Thanks!!
Those are Norton Commando chrome reverse-cone megaphones... about 34" long (one on each side)
aka peashooters
True that! Here's a link to a short video of it (before I painted it) just idling so you can hear it: https://vimeo.com/63709242

As you see in the video, I had fit 4 Mikuni flat-slides on the GL for a while, but apparently the GL1000 made too much vacuum at idle and on the over-run. The slides would hang and not return completely to idle... not good. I even beefed up the slide springs and still had issues so I went to the downdraft VMAX Mikinis. The flat-slides were being sucked against the carb body and would stick until vacuum dropped. As a test, I could pull in the clutch on decel (where they were hanging) and the idle speed would then resume. (lower vacuum at reduced rpm)

I was just gonna buy a Weber carb kit from Randakk, but it's pricey, and besides I like to tinker! Also, with the shorter Venture/VMAX carbs I can still lower the tank side panels for access to stuff. Looks like the taller manifolds & Webers get in the way of that.

Anyway... like I said she's sick right now. An extremely grabby and noisy clutch. I'll attempt to fix it again someday. Too swamped with work (self-employed) to even have time to ride my other bikes that run!
Cheers,
BLIGHT
'76 GL1000
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Re: VMAX Downdraft Carb conversion

#47

Post by Twostick »

BLIGHT wrote:
Twostick wrote:Love the bike!

What kind of mufflers are those?

Kevin
Thanks!!
Those are Norton Commando chrome reverse-cone megaphones... about 34" long (one on each side)
Where do you get them?

I've seen lots of different mufflers on these builds and lots of them are alright but those in my eyes anyway are the only ones that perfectly suit a first gen GW.

Kevin
Some people are like Slinkies, not really good for anything but they bring a smile to your face when pushed down the stairs.
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BLIGHT
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Re: VMAX Downdraft Carb conversion

#48

Post by BLIGHT »

Twostick wrote:
BLIGHT wrote:
Twostick wrote:Love the bike!

What kind of mufflers are those?

Kevin
Thanks!!
Those are Norton Commando chrome reverse-cone megaphones... about 34" long (one on each side)
Where do you get them?

I've seen lots of different mufflers on these builds and lots of them are alright but those in my eyes anyway are the only ones that perfectly suit a first gen GW.

Kevin
Yeah, I love the look and sound too... they are long and suit the long wheelbase of the GL1000.
I got 'em on ebay. Here's a link that will be active for a while, (may not be if they sell out later) : http://tinyurl.com/hjsq4js

Actually I just went out in the garage and measured.... the muffs are 26 3/4" long (not 34!)
Go to ebay and type Norton Commando Muffler and you'll see a bunch of sellers.
Some offerings have a seam, others are seamless like the ones I got.

I have a similar pair of rev-cone peashooters on my 06 Triumph Thruxton, but in SS and made by EPCO:

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Re: VMAX Downdraft Carb conversion

#49

Post by Twostick »

tumb2 tumb2

Kevin
Some people are like Slinkies, not really good for anything but they bring a smile to your face when pushed down the stairs.
guidowitz
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Re: VMAX Downdraft Carb conversion

#50

Post by guidowitz »

Probably my favorite Goldwing of all time...
David
Dept of Veterans Affairs...(Retired, 1985-2014).

1976 GL 1000 (current ride)
Previous rides:
1971 Triumph Bonneville
1966 Harley "FL" Police Bike
1951 Triumph Thunderbird
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BLIGHT
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Re: VMAX Downdraft Carb conversion

#51

Post by BLIGHT »

guidowitz wrote:Probably my favorite Goldwing of all time...
Wow, you guys are great!
Thanks again for all the nice comments!
BLIGHT
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randakk
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Re: VMAX Downdraft Carb conversion

#52

Post by randakk »

Awesome work! I like very much.
Randall Washington (Randakk)
Retired Founder - www.randakks.com/
Curator - www.facebook.com/groups/CarburetorAppreciationSociety

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Re: VMAX Downdraft Carb conversion

#53

Post by duke182 »

Great build.
Congratulations on botm
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Re: VMAX Downdraft Carb conversion

#54

Post by DaveyG »

What year vmax and venture used these carbs?
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Re: VMAX Downdraft Carb conversion

#55

Post by BLIGHT »

"What year vmax and venture used these carbs?"

I don't know... I just found them on ebay. Seems like 1986-1990 era. Here's some:
http://www.ebay.com/itm/Vmax-carburetor ... JT&vxp=mtr
The linkage is a pain in case you are considering doing this!
BLIGHT
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Re: VMAX Downdraft Carb conversion

#56

Post by DaveyG »

Dang! For that money I could build an EFI setup!
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Re: VMAX Downdraft Carb conversion

#57

Post by desertrefugee »

That's pie in the sky price there. I had a hard time selling a VMax rack for $300. Clean and ready to hang.
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Re: VMAX Downdraft Carb conversion

#58

Post by DaveyG »

Current cheapest set on eBay $125 plus shipping. Efi hard parts are $20 (used cbr throttle bodies, injectors, wiring) and the ms ecu is $300 so wouldn't be very far off from swapping to the vmax carbs. And instead of jet/needle changes, all it takes is a few keystrokes...
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BLIGHT
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Re: VMAX Downdraft Carb conversion

#59

Post by BLIGHT »

Then you need to do the EFI.... simple!
'76 GL1000
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Re: VMAX Downdraft Carb conversion

#60

Post by DaveyG »

I would. But I still don't got $300 haha
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