Mikuni Carb Conversion


Information and questions on GL1000 Goldwings (1975-1979)
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barryweber111
Posts: 3
Joined: Thu Mar 28, 2019 9:28 pm
Location: Houston, Texas
Motorcycle: 1977 GL1000

Mikuni Carb Conversion

Post by barryweber111 »



Hi All,
Thanks in advance for your input. Last week I purchased a 1977 GL1000 with 32K miles. I am trying to decide if I should keep the carb conversion or switch back to stock carbs. Asking for your advice.

The bike has the Dyna Ignition upgrade and carb conversion "VM26 Mikuni Carbs with accelerator pump (4 Mikuni Carbs)". From with I can tell everything else seems stock. The bike is in above average condition. The bike idles well and accelerates great but awful with everything else induction wise. It surges and has a slight misfire during steady state riding, backfires on deceleration, plugs are wet and dark so I'm thinking it is running rich and takes 3-5 seconds to return to idle after letting go of the throttle. I think the last issue is because the linkage to the right bank of carbs has a lot of slop in it or misadjusted. One thing about the setup is it takes some effort to twist the throttle off idle but suddenly gets easy causing an overrev - no amount of throttle finesse seems to prevent me from doing jack rabbit starts.
In the last four years the bike has been through 3 owners - I am number 4. Only 50 miles has been put on the bike since early 2015. The previous two owners sold it because they could not sort out these problems. BTW - I'm assuming these are carb tuning/repair issues not the Dyna upgrade or some other issue.

So should I put my resources into sorting out the Mikuni carbs or start searching for a stock assembly? I am OK with rebuilding carbs but not sure I can handle sorting out these problems. I searched online and have not found any info on this carb conversion. Has any of you heard of a Mikuni VM26 conversion?

One last question. If I pull the Mikuni carbs off is there a market for this upgrade?

Left Bank Mikuni Carbs
Left Bank Mikuni Carbs



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DenverWinger
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Re: Mikuni Carb Conversion

Post by DenverWinger »

You might try posting this over at the Naked Goldwings site (ngwclub.com), That site dedicated to the 4 cylinder 'Wings and by the looks of things over there these guys have tried every mod under the sun.... :)
♫ 99 Little Bugs in the Code, ♪
♪ 99 Bugs in the Code. ♫ :(
♫ Take one down, Patch it around, ♪
♫ 127 Little Bugs in the Code. ♫ ♪ :shock:

~Mark
Old Fogey
Posts: 839
Joined: Fri Oct 30, 2009 2:09 am
Location: Glasgow Scotland
Motorcycle: 1976 GL1000
1979 GL1000
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Re: Mikuni Carb Conversion

Post by Old Fogey »

Those are not like any VM26 that I've seen, This is a VM26


Any better pictures?
'Impossible' is just a level of difficulty! The only stupid question is the one you didn't ask first!

( Seriously, you haven't read all 115 pages of my http://www.wingovations.com website ?? :shock: )
barryweber111
Posts: 3
Joined: Thu Mar 28, 2019 9:28 pm
Location: Houston, Texas
Motorcycle: 1977 GL1000

Re: Mikuni Carb Conversion

Post by barryweber111 »

I got the VM26 conversion from an old document that came with the bike. As I was researching online I realized what's on the bike does not match the pictures of Mikuni VM26 that I see online. Hard to get pictures and I don't see much on the carbs themselves, I just figured when I pull this carb assembly I can sort that out.
I'm thinking I will source a 1977 Honda carb assembly and get the bike running in stock configuration. Then decide if I want to reinstall this assembly. I've attached a couple pictures and not sure there is enough there to figure out what Mikuni carb is on the bike.

I'm coming to the conclusion that in the Goldwing world carb conversions are not unusual with many one off setup's. Not sure if that is because the Goldwing engine readily accepts carb changes or maybe its easy to up the performance if these engines by changing carbs.
Attachments

Mikuni KOGYO Pic 1
Mikuni KOGYO Pic 1


Mikuni KOGYO Pic 2
Mikuni KOGYO Pic 2

Old Fogey
Posts: 839
Joined: Fri Oct 30, 2009 2:09 am
Location: Glasgow Scotland
Motorcycle: 1976 GL1000
1979 GL1000
Contact:

Re: Mikuni Carb Conversion

Post by Old Fogey »

You can use any 75-77 set to get the best performance. Look for 755A, 758A, 764A stamped on the carb mounting flange.


'Impossible' is just a level of difficulty! The only stupid question is the one you didn't ask first!

( Seriously, you haven't read all 115 pages of my http://www.wingovations.com website ?? :shock: )
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