carbs syncadapter, 5 or 6mm?

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alebal
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carbs syncadapter, 5 or 6mm?

Post by alebal »

https://www.ebay.com/itm/401208535840?e ... R4yyvounYw

I would like to synchronize the carburetors, some work was done, the engine was removed, cables changed, and the synchronization was never done.

I would like to do it with a tube...

so as not to spend too much on equipment to be used only once and then thrown away (here in the Dominican Republic they don't even know what a synchronization tool is, I would have to travel 300km to find one)...

but I think I can having to find at least the adapters, to avoid having air leaks, but on my trudy vs700 will they be 5 or 6mm?

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hillsy v2
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Re: carbs syncadapter, 5 or 6mm?

Post by hillsy v2 »

I'm pretty sure they are M6 - but easiest to take the plug bolt out and check.

navigator
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Re: carbs syncadapter, 5 or 6mm?

Post by navigator »

Your 700 needs 5mm adapters. long ones are easier to install.
Don't drop the small sealing washers on the screws. :bonk:

alebal
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Re: carbs syncadapter, 5 or 6mm?

Post by alebal »

hillsy v2 wrote:
Wed Jan 24, 2024 12:40 am
I'm pretty sure they are M6 - but easiest to take the plug bolt out and check.
yes, the problem is that these are all my powerful measurement tools.

Image

However, I would say 5... probably...

navigator
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Re: carbs syncadapter, 5 or 6mm?

Post by navigator »

Trust me....5

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hillsy v2
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Re: carbs syncadapter, 5 or 6mm?

Post by hillsy v2 »

Nav has confirmed it - but if you're still unsure pop out a bolt from one of the engine side covers. They are all M6

Lechy
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Re: carbs syncadapter, 5 or 6mm?

Post by Lechy »

Grow old disgracefully young man.

alebal
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Re: carbs syncadapter, 5 or 6mm?

Post by alebal »

hi guys,

for a couple of weeks I've been trying to synchronize the carburetors... without success...

first a stripped screw... then I solved it with the screw, dismantled everything, prepared everything and tried to synchronize with inconceivable results...

I then discovered that the hose I bought, near the engine, was heating up, softening, crushing and blocking...

I bought a couple of feet of rigid hose, reassembled and prepared everything, and tried to synchronize again, again new with absurd results, I then discovered that the smaller tube heated up and softened even if further away...

I bought 20 feet of rigid tube, disassembled and prepared everything again and tried to synchronize again... again results absurd as you can see in the videos...

[YoutubeURL][/YoutubeURL]

now the tube doesn't crush and there doesn't seem to be any leaks, but something is strange...

the adjustment cable doesn't seem to do anything, I even got to the point where it wasn't even under tension anymore and I haven't noticed any big changes, when unscrewing or retightening the levels sometimes seem to get closer but only to move away at the first acceleration, the idle speed seems high with a warm engine, I thought it would be lowered a little by synchronizing the carburettors, but it doesn't seem to change, the idle speed screw is completely unscrewed...

sometimes it seems to miss some bursts, but I think it's the fuel's fault, maybe I put the tank a little too low...

something seems to distort the settings and levels, but at this point I don't really understand what could it be... suggestions?

Lechy
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Re: carbs syncadapter, 5 or 6mm?

Post by Lechy »

Read the link I posted and watch the vids. it seems you have the idle adjustment pretty close but have not adjusted the run. There are 2 adjustment screws, both on the front carb.
Grow old disgracefully young man.

navigator
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Re: carbs syncadapter, 5 or 6mm?

Post by navigator »

Before you sync, make sure you have plenty of slack in the cable at the grip.
It sounds as if the throttle is being held open by the grip, not able to return to the closed position.

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Herb
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Re: carbs syncadapter, 5 or 6mm?

Post by Herb »

I am not familiar with the cable setup on these bikes but on the 1400 it is impossible to balance the carbs, at idle, if the splitter is not properly anchored.
I can't seem to win the lottery. I think I have used up all of my good luck riding motorcycles.

alebal
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Re: carbs syncadapter, 5 or 6mm?

Post by alebal »

I'm confused... in the video there is little light and you can't see much, but he seems to only touch one screw, the same one I used too, I also looked for other videos and they all seem to always use the same screw.

I looked for the other adjustment screws in the manual, but some writings are missing...

Image

just the ones I need, even the manual isn't very clear about synchronization... Is 1 the screw that regulates the minimum synchronization?

My throttle cable is also too long, unfortunately remade by some Dominican idiot after it broke due to rust, I had to add bolts and washers to be able to use it decently...
[YoutubeURL]
https://youtube.com/shorts/WnFGtynQIso?feature=shared[/YoutubeURL]

(the original cable is short because the handlebar is high...)

but the carburetors seem to close well... I think. ..

[YoutubeURL]
https://youtube.com/shorts/WnFGtynQIso?feature=shared
[/YoutubeURL]

[YoutubeURL]
https://youtube.com/shorts/Ms9AtjUfzhg?feature=shared
[/YoutubeURL]

can you explain to me a little better what I should do?

Lechy
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Re: carbs syncadapter, 5 or 6mm?

Post by Lechy »

#4 is the idle adjust, #3 is the running adjust.
Grow old disgracefully young man.

navigator
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Re: carbs syncadapter, 5 or 6mm?

Post by navigator »

alebal wrote:
Mon Mar 25, 2024 4:25 pm
I'm confused... in the video there is little light and you can't see much, but he seems to only touch one screw, the same one I used too, I also looked for other videos and they all seem to always use the same screw.

I looked for the other adjustment screws in the manual, but some writings are missing...

Image

just the ones I need, even the manual isn't very clear about synchronization... Is 1 the screw that regulates the minimum synchronization?

My throttle cable is also too long, unfortunately remade by some Dominican idiot after it broke due to rust, I had to add bolts and washers to be able to use it decently...
[YoutubeURL]
https://youtube.com/shorts/WnFGtynQIso?feature=shared[/YoutubeURL]

(the original cable is short because the handlebar is high...)

but the carburetors seem to close well... I think. ..

[YoutubeURL]
https://youtube.com/shorts/WnFGtynQIso?feature=shared
[/YoutubeURL]

[YoutubeURL]
https://youtube.com/shorts/Ms9AtjUfzhg?feature=shared
[/YoutubeURL]

can you explain to me a little better what I should do?
OK so the video of the grip shows that the cable is not stock, I see no means of adjustment at the grip.
[YoutubeURL]
https://youtube.com/shorts/WnFGtynQIso?feature=shared
[/YoutubeURL]
However the linkage appears to close with sufficient slack, so you are good to go.
[YoutubeURL]
https://youtube.com/shorts/Ms9AtjUfzhg?feature=shared
[/YoutubeURL]

No need to adjust screw #1

You have the idle sync pretty close by adjusting the barrel #4 on the rear cable in this drawing, while the engine is idling.
Next hold the throttle open to about 2000 rpm (or have someone assist you holding the grip) then adjust barrel #3 on the front cable until the high speed sync balances on your tube setup.


Image

alebal
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Re: carbs syncadapter, 5 or 6mm?

Post by alebal »

so, I like the 3, I can adjust it with my fingers and as soon as I touched it the levels moved, as if something was finally really happening...

I just fiddled with it a bit quickly today and in an instant I was able to adjust the levels at minimum rpm, but as soon as I accelerate everything skyrockets...

[YoutubeURL][/YoutubeURL]

but I think I've understood that 3 should be used to adjust the levels at 2-3000 rpm (approximately, because Trudy doesn't have an engine rpm counter) then with 4 you adjust the levels at minimum engine rpm, right?


I hope that in the process the minimum engine rpm will also be lowered, because it also seems a little higher than before.

unfortunately I have to move in a few days and it will be a mess, but I want to repeat the whole procedure correctly as soon as I'm settled.

In the meantime, any suggestions? advice? corrections?

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