VMAX Downdraft Carb conversion
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- robin1731
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Re: VMAX Downdraft Carb conversion
1976 Goldwing Super Sport
1985 Honda Elite
1976 KZ900 Dragbike
1992 ZX7 Dragbike (KZ900 style motor w/NOS)
and a rotation of various purchases
Randakk approved Carb Rebuilder
1985 Honda Elite
1976 KZ900 Dragbike
1992 ZX7 Dragbike (KZ900 style motor w/NOS)
and a rotation of various purchases
Randakk approved Carb Rebuilder
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- Lead Member
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- Joined: Tue May 24, 2016 3:37 pm
Re: VMAX Downdraft Carb conversion
Hi! I'm currently doing the same mod to one of my GL1100.
A little curious about how you linked the throttle from the left pair to the right pair...
Think you for inspiration!
Jonas from Sweden
A little curious about how you linked the throttle from the left pair to the right pair...
Think you for inspiration!
Jonas from Sweden
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- Rat
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Re: VMAX Downdraft Carb conversion
Hi Jonas and Welcome.
Take a minute and post a bit about yourself in the Welcome and Introduction Forum.
Gord
Take a minute and post a bit about yourself in the Welcome and Introduction Forum.
Gord
"I'd rather Ride than Shine"
‘14 KLR650 ... not a rat ... yet
‘84 GL1200i ‘R2B6' (Rat to Be 6, the last, adopted by twowings)
My Original 'RAT' was a hybrid '82 CB900/1100F
‘14 KLR650 ... not a rat ... yet
‘84 GL1200i ‘R2B6' (Rat to Be 6, the last, adopted by twowings)
My Original 'RAT' was a hybrid '82 CB900/1100F
- BLIGHT
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- Location: Monterey-Salinas CA
Re: VMAX Downdraft Carb conversion
HI Jonas,
I used a long threaded rod with rod-ends on it (adjustable) it kind of copied the V-Max method, but the carbs are farther apart than on the Max-Venture carb setup.
I used a single throttle cable to actuate the rider's left side carb, and then the rod linkage crossed over to work the opposite side.
Got it in my mind that was the way to do it, and didn't even think about the split (2 to 1) cables they make until later.
That would have been far easier if each cable had an adjustment for sync of the butterflies.
I may do that someday, although what I made seems to work fine.
They also make dual cable twist-grips, so you just run a separate throttle cable to each carb like they used to on Triumphs and BSA's!
I know you already have the carbs, but it you got two Yamaha Virago 535 setups they were the same bodies and guts, but in pairs ready to accept a throttle cable end without any other adaptation (except for the width between them on the GL1000 heads)
Good Luck!
BLIGHT
I used a long threaded rod with rod-ends on it (adjustable) it kind of copied the V-Max method, but the carbs are farther apart than on the Max-Venture carb setup.
I used a single throttle cable to actuate the rider's left side carb, and then the rod linkage crossed over to work the opposite side.
Got it in my mind that was the way to do it, and didn't even think about the split (2 to 1) cables they make until later.
That would have been far easier if each cable had an adjustment for sync of the butterflies.
I may do that someday, although what I made seems to work fine.
They also make dual cable twist-grips, so you just run a separate throttle cable to each carb like they used to on Triumphs and BSA's!
I know you already have the carbs, but it you got two Yamaha Virago 535 setups they were the same bodies and guts, but in pairs ready to accept a throttle cable end without any other adaptation (except for the width between them on the GL1000 heads)
Good Luck!
BLIGHT
'76 GL1000
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Re: VMAX Downdraft Carb conversion
Hi, Thanks! I should have gone with the 1-2 split...... why didnt i think of that... worked on bikes my entire life... but now I will link (have not looked here for a couple of days and have bought material for a link).
Cheers!
Cheers!
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Re: VMAX Downdraft Carb conversion
Hey, Blight-
Looking through your thread, I didn't see it:
What length shocks are those?
They appear to be about three inches longer than stock!
Any head shake issues?
Are they eBay generics?
Thanks,
Scott
Looking through your thread, I didn't see it:
What length shocks are those?
They appear to be about three inches longer than stock!
Any head shake issues?
Are they eBay generics?
Thanks,
Scott
Ride like you mean it.
- BLIGHT
- Chrome Member
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- Joined: Sun Feb 03, 2013 2:58 am
- Location: Monterey-Salinas CA
Re: VMAX Downdraft Carb conversion
HI Scott,
They were longer ebay shocks and no handling issues or head shake.
The shocks were longer, (13"+) and changed the swingarm angle, and caused a cyclic vibration (universal joint angle)
So, I went back to a stock shock length... longer shocks on a GL is not a good idea.
The GL uses a simple universal joint, and at larger angles, the output shaft speeds up and slows down as it rotates.
If they had used a Cardan-style (double universal) or CV-style there would be no such issue, and you could use longer shocks.
I put the universal shocks on my Thruxton with a chain drive and no such issue!
BLIGHT
They were longer ebay shocks and no handling issues or head shake.
The shocks were longer, (13"+) and changed the swingarm angle, and caused a cyclic vibration (universal joint angle)
So, I went back to a stock shock length... longer shocks on a GL is not a good idea.
The GL uses a simple universal joint, and at larger angles, the output shaft speeds up and slows down as it rotates.
If they had used a Cardan-style (double universal) or CV-style there would be no such issue, and you could use longer shocks.
I put the universal shocks on my Thruxton with a chain drive and no such issue!
BLIGHT
'76 GL1000
- BLIGHT
- Chrome Member
- Posts: 110
- Joined: Sun Feb 03, 2013 2:58 am
- Location: Monterey-Salinas CA
Re: VMAX Downdraft Carb conversion
Reminds me of what my grandpa used to say...DaveyG wrote:I would. But I still don't got $300 haha
"If we had some ham, we could have some ham and eggs.... if we had some eggs"
'76 GL1000
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- Cast Iron Member
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- Joined: Sun Oct 23, 2016 4:15 am
Re: VMAX Downdraft Carb conversion
Thanks for that info, Blight!
That's really too bad the longer shocks didn't work out, I usually end up raising the rear of my bikes and I like how that changes the handling.
I believe the stock shocks are about 13 1/4", though.
What length were the long ones that caused the vibrations?
What speeds did the vibration happen, or was it all the time?
Thanks again,
Scott
That's really too bad the longer shocks didn't work out, I usually end up raising the rear of my bikes and I like how that changes the handling.
I believe the stock shocks are about 13 1/4", though.
What length were the long ones that caused the vibrations?
What speeds did the vibration happen, or was it all the time?
Thanks again,
Scott
Ride like you mean it.
- BLIGHT
- Chrome Member
- Posts: 110
- Joined: Sun Feb 03, 2013 2:58 am
- Location: Monterey-Salinas CA
Re: VMAX Downdraft Carb conversion
Scott,BigSherm wrote:Thanks for that info, Blight!
That's really too bad the longer shocks didn't work out, I usually end up raising the rear of my bikes and I like how that changes the handling.
I believe the stock shocks are about 13 1/4", though.
What length were the long ones that caused the vibrations?
What speeds did the vibration happen, or was it all the time?
Thanks again,
Scott
The OEM shocks (back on the bike now) are 13.5" and the ebay universals were about 14.5" eye to eye.
Not that much difference, right?
The vibration was all the time, and sometimes kind of cyclic, like a wheel out of balance.
Went away immediately once when the stockers were put back in place.
BLIGHT
'76 GL1000
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Re: VMAX Downdraft Carb conversion
Man, that's great info, saving me a lot of money, time, and hassle going through it myself.
One reason this site is so great!
Thanks again,
Scott
One reason this site is so great!
Thanks again,
Scott
Ride like you mean it.
- 5speed
- Honored Life Member
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- Location: Nova Scotia Canada
Re: VMAX Downdraft Carb conversion
love your bike..looks like it's going 100 mph sitting there.
I've always wondered and asked before...do adding down draft carbs affect your leg room?
it looks like they would be very close to your knees.
I've always wondered and asked before...do adding down draft carbs affect your leg room?
it looks like they would be very close to your knees.
1982 1100 standard. (sold)
1986 Yamaha FJ1200
2000 Yamaha Roadstar
1976 GoldWing. running but not on the road
1978 Goldwing. future cafe project.
2019 Can-Am ryker (boss's new ride)
2002 Shadow American Classic(sold)
1983 Shadow 500. (sold)
1986 Yamaha FJ1200
2000 Yamaha Roadstar
1976 GoldWing. running but not on the road
1978 Goldwing. future cafe project.
2019 Can-Am ryker (boss's new ride)
2002 Shadow American Classic(sold)
1983 Shadow 500. (sold)
- BLIGHT
- Chrome Member
- Posts: 110
- Joined: Sun Feb 03, 2013 2:58 am
- Location: Monterey-Salinas CA
Re: VMAX Downdraft Carb conversion
Thank you...5speed wrote:love your bike..looks like it's going 100 mph sitting there.
I've always wondered and asked before...do adding down draft carbs affect your leg room?
it looks like they would be very close to your knees.
Yes, they do hit your knee, more on the left side IIRC due to the cylinders being offset.
I just slide back a little on the seat and it's OK.
'76 GL1000
- 5speed
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Re: VMAX Downdraft Carb conversion
well darn. lolBLIGHT wrote:[
Thank you...
Yes, they do hit your knee, more on the left side IIRC due to the cylinders being offset.
I just slide back a little on the seat and it's OK.
I'm 6'4"..I guess down draft carb conversions are off the list.
1982 1100 standard. (sold)
1986 Yamaha FJ1200
2000 Yamaha Roadstar
1976 GoldWing. running but not on the road
1978 Goldwing. future cafe project.
2019 Can-Am ryker (boss's new ride)
2002 Shadow American Classic(sold)
1983 Shadow 500. (sold)
1986 Yamaha FJ1200
2000 Yamaha Roadstar
1976 GoldWing. running but not on the road
1978 Goldwing. future cafe project.
2019 Can-Am ryker (boss's new ride)
2002 Shadow American Classic(sold)
1983 Shadow 500. (sold)
- BLIGHT
- Chrome Member
- Posts: 110
- Joined: Sun Feb 03, 2013 2:58 am
- Location: Monterey-Salinas CA
Re: VMAX Downdraft Carb conversion
I'm 6-0" (and shrinking) and my left knee does smack the air-filter.5speed wrote:well darn. lolBLIGHT wrote:[
Thank you...
Yes, they do hit your knee, more on the left side IIRC due to the cylinders being offset.
I just slide back a little on the seat and it's OK.
I'm 6'4"..I guess down draft carb conversions are off the list.
I was gonna move the pegs and controls back since my GL is 'cafe-styled', and that would fix it.
Looks like a lotta work though, and I had already moved on to the next project.
Besides.... the snatchy-grabby clutch issue has pretty much caused me to park it and just look at it!
BLIGHT
'76 GL1000
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