Carb sync

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Demonsinmysemen

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Hey, everyone. Hope everyone is doing alright in these times. Just trying to stay safe and busy myself. Speaking of busy, I decided to clean my carbs because the bike was sitting for a while. All cleaned up and running a bit better, however, trying to sync up the carbs is proving to be annoying. Carb #1 and #2 are fine. #3 is okay but #4 just will not sync up. I could barely get under 40 on the vacuum. Any ideas?
 

Fire-medic

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I guess check for a vacuum leak? Spray some starting fluid around that carb and the boots, to see if the revs pick-up, that's the area of the leak. Maybe pop-off the CV diaphragm cap and ensure that it's properly-seated.
 

Demonsinmysemen

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I guess check for a vacuum leak? Spray some starting fluid around that carb and the boots, to see if the revs pick-up, that's the area of the leak. Maybe pop-off the CV diaphragm cap and ensure that it's properly-seated.
I'll give that a whirl but I'm pretty sure it's seated well. I'll check the diaphragm for sure. She rides well, which is strange.
 

dannymax

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You need to tweak your sync linkage tabs to get more travel on that carb adjuster. A side impact, like toppling over off the stand can, can cause that.
 

Demonsinmysemen

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You need to tweak your sync linkage tabs to get more travel on that carb adjuster. A side impact, like toppling over off the stand can, can cause that.
I'm a bit confused. Sorry, I'm a tad new to messing with carbs.I have a regular carb synchroniser. Not the mercury one. Anyway, I'm not even sure what that part is exactly.
 

dannymax

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I'm a bit confused. Sorry, I'm a tad new to messing with carbs.I have a regular carb synchroniser. Not the mercury one. Anyway, I'm not even sure what that part is exactly.
The type of sync instrument you have isn't the issue. It's strictly mechanical. Tip the carb rack upside down and study the linkage...your objective is to get more travel in the screw that has bottomed out.
Easier said than done unfortunately.
 

Fire-medic

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Bend any tab you see, three if you need-to (that shouldn't be-necessary). You could also substitute a slightly-longer screw, if you had-to, though bending the tab(s) is easiest. You want to-avoid spring-crush, where the spring has binding coils.

VMax synch screws.01.jpg VMax synch screws.02.jpg
 
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Demonsinmysemen

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The type of sync instrument you have isn't the issue. It's strictly mechanical. Tip the carb rack upside down and study the linkage...your objective is to get more travel in the screw that has bottomed out.
Easier said than done unfortunately.
I see. Seems more annoying than difficult, it seems. Thank you so much for the help. Stay safe, brother.
 

Demonsinmysemen

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Demonsinmysemen

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Bend any tab you see, three if you need-to (that shouldn't be-necessary). You could also substitute a slightly-longer screw, if you had-to, though bending the tab(s) is easiest. You want to-avoid spring-crush, where the spring has binding coils.

View attachment 71355 View attachment 71356
Which tab should be bent? It looks to be a pretty strong metal but I haven't taken the carb off just yet. Trying to do it while on the bike.
 

Demonsinmysemen

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Make sure the screw isn't stripped, and IS moving the linkage. It happens.
Thanks for that. I got around to taking the screw out. She looks a bit stripped, however I had her tightened all the way and it seemed to be getting closer to the desired 20 on the gauge. Someone on the chat had suggested I swap the screw out with a longer one. I would just pop into home depot and look for one, but for some I reason, I don't think I should. Any suggestions?
 

Demonsinmysemen

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I guess check for a vacuum leak? Spray some starting fluid around that carb and the boots, to see if the revs pick-up, that's the area of the leak. Maybe pop-off the CV diaphragm cap and ensure that it's properly-seated.
Getting a better look, I'm positive you're right about some sort of side impact. The previous owner swapped out the water pump and lo and behold, problem on this side of the carb. It looks as if I'm going to have to bend the tabs, as suggested. Any suggestions on where to get new screws? They are a bit stripped.
 

Fire-medic

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I do not recommend trying to bend the tabs while fastened to the carb set. The soft metal will easily-break!

Probably the safest way to bend any steel parts is to remove them from the die-cast pot-metal carb bodies. Take lots of pictures, and make some notes, to help you get everything re-assembled. Clamp the piece into a vise, and use a large adjustable jaw wrench, like a Crescent wrench, a longer one provides you with more leverage. Make sure that you know which-way you need to-go, bending it. This process is 'cold-setting,' and you probably don't need to move things much. Try to determine before everything is apart, what direction you need-to bend it, and how-far. If the item cannot be easily-clamped in a vise, you might find it necessary to use two Crescent wrenches.

Here's a technique for getting things bent properly. Use a coil of baling wire, clip-off about a 4" long piece from the roll of wire, and bend it to the shape of the bracket. Now you have a template to use, to compare how-much you've bent the tab. You could also use a scrap of solid copper wire, but you better use at-least a 12-gauge wire, because as-malleable as copper wire is, it won't hold its shape for purposes of comparison to your bent bracket, if you use anything of a higher numerical value/smaller diameter (gauge) than that.

My experience with threaded fasteners under light loads like these screws, is that you would have to be really working at it to strip one of them. They don't have-to move very-much so there really-isn't much torque on them, nor is much force needed to move them in/out. I'd use a magnifying glass to carefully check the screws' threads for deformities.

I dunno where you live in Miami, but I've found a good selection of metric fasteners at the Ace Hardware at 6448 So. Dixie Hwy. So. Miami 33143 by Sunset Drive. It's just-north of where the Snapper Creek Expressway (SR 878) dumps-out onto US-1, north of the Dadeland Mall, it's in a strip mall building set way-back from the road. They have metric stainless steel stuff too, I'd buy some SS 4 mm machine screws for the float bowls, get 'em in allen heads. You could swap-out the CV diaphragm cap fasteners too, in-fact, bring one of each, and swap 'em all out!
 
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Demonsinmysemen

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I do not recommend trying to bend the tabs while fastened to the carb set. The soft metal will easily-break!

Probably the safest way to bend any steel parts is to remove them from the die-cast pot-metal carb bodies. Take lots of pictures, and make some notes, to help you get everything re-assembled. Clamp the piece into a vise, and use a large adjustable jaw wrench, like a Crescent wrench, a longer one provides you with more leverage. Make sure that you know which-way you need to-go, bending it. This process is 'cold-setting,' and you probably don't need to move things much. Try to determine before everything is apart, what direction you need-to bend it, and how-far. If the item cannot be easily-clamped in a vise, you might find it necessary to use two Crescent wrenches.

Here's a technique for getting things bent properly. Use a coil of baling wire, clip-off about a 4" long piece from the roll of wire, and bend it to the shape of the bracket. Now you have a template to use, to compare how-much you've bent the tab. You could also use a scrap of solid copper wire, but you better use at-least a 12-gauge wire, because as-malleable as copper wire is, it won't hold its shape for purposes of comparison to your bent bracket, if you use anything of a higher numerical value/smaller diameter (gauge) than that.

My experience with threaded fasteners under light loads like these screws, is that you would have to be really working at it to strip one of them. They don't have-to move very-much so there really-isn't much torque on them, nor is much force needed to move them in/out. I'd use a magnifying glass to carefully check the screws' threads for deformities.

I dunno where you live in Miami, but I've found a good selection of metric fasteners at the Ace Hardware at 6448 So. Dixie Hwy. So. Miami 33143 by Sunset Drive. It's just-north of where the Snapper Creek Expressway (SR 878) dumps-out onto US-1, north of the Dadeland Mall, it's in a strip mall building set way-back from the road. They have metric stainless steel stuff too, I'd buy some SS 4 mm machine screws for the float bowls, get 'em in allen heads. You could swap-out the CV diaphragm cap fasteners too, in-fact, bring one of each, and swap 'em all out!
This is an EPIC response!!!! Thank you!!! It really helps me envision and paint the picture of what I should do. It's something I've never done before or even heard of doing. I am a bit apprehensive of doing this simply because I was confused about it. This hugely helps. Now I just have to do it.
 

Demonsinmysemen

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Holy crap! I've just realised that you live in Miami! Don't know how I didn't realize that sooner with that detailed response. Well, I feel dumb. I live in Kendall, so that ace hardware is definitely close by me.
I do not recommend trying to bend the tabs while fastened to the carb set. The soft metal will easily-break!

Probably the safest way to bend any steel parts is to remove them from the die-cast pot-metal carb bodies. Take lots of pictures, and make some notes, to help you get everything re-assembled. Clamp the piece into a vise, and use a large adjustable jaw wrench, like a Crescent wrench, a longer one provides you with more leverage. Make sure that you know which-way you need to-go, bending it. This process is 'cold-setting,' and you probably don't need to move things much. Try to determine before everything is apart, what direction you need-to bend it, and how-far. If the item cannot be easily-clamped in a vise, you might find it necessary to use two Crescent wrenches.

Here's a technique for getting things bent properly. Use a coil of baling wire, clip-off about a 4" long piece from the roll of wire, and bend it to the shape of the bracket. Now you have a template to use, to compare how-much you've bent the tab. You could also use a scrap of solid copper wire, but you better use at-least a 12-gauge wire, because as-malleable as copper wire is, it won't hold its shape for purposes of comparison to your bent bracket, if you use anything of a higher numerical value/smaller diameter (gauge) than that.

My experience with threaded fasteners under light loads like these screws, is that you would have to be really working at it to strip one of them. They don't have-to move very-much so there really-isn't much torque on them, nor is much force needed to move them in/out. I'd use a magnifying glass to carefully check the screws' threads for deformities.

I dunno where you live in Miami, but I've found a good selection of metric fasteners at the Ace Hardware at 6448 So. Dixie Hwy. So. Miami 33143 by Sunset Drive. It's just-north of where the Snapper Creek Expressway (SR 878) dumps-out onto US-1, north of the Dadeland Mall, it's in a strip mall building set way-back from the road. They have metric stainless steel stuff too, I'd buy some SS 4 mm machine screws for the float bowls, get 'em in allen heads. You could swap-out the CV diaphragm cap fasteners too, in-fact, bring one of each, and swap 'em all out!
I do not recommend trying to bend the tabs while fastened to the carb set. The soft metal will easily-break!

Probably the safest way to bend any steel parts is to remove them from the die-cast pot-metal carb bodies. Take lots of pictures, and make some notes, to help you get everything re-assembled. Clamp the piece into a vise, and use a large adjustable jaw wrench, like a Crescent wrench, a longer one provides you with more leverage. Make sure that you know which-way you need to-go, bending it. This process is 'cold-setting,' and you probably don't need to move things much. Try to determine before everything is apart, what direction you need-to bend it, and how-far. If the item cannot be easily-clamped in a vise, you might find it necessary to use two Crescent wrenches.

Here's a technique for getting things bent properly. Use a coil of baling wire, clip-off about a 4" long piece from the roll of wire, and bend it to the shape of the bracket. Now you have a template to use, to compare how-much you've bent the tab. You could also use a scrap of solid copper wire, but you better use at-least a 12-gauge wire, because as-malleable as copper wire is, it won't hold its shape for purposes of comparison to your bent bracket, if you use anything of a higher numerical value/smaller diameter (gauge) than that.

My experience with threaded fasteners under light loads like these screws, is that you would have to be really working at it to strip one of them. They don't have-to move very-much so there really-isn't much torque on them, nor is much force needed to move them in/out. I'd use a magnifying glass to carefully check the screws' threads for deformities.

I dunno where you live in Miami, but I've found a good selection of metric fasteners at the Ace Hardware at 6448 So. Dixie Hwy. So. Miami 33143 by Sunset Drive. It's just-north of where the Snapper Creek Expressway (SR 878) dumps-out onto US-1, north of the Dadeland Mall, it's in a strip mall building set way-back from the road. They have metric stainless steel stuff too, I'd buy some SS 4 mm machine screws for the float bowls, get 'em in allen heads. You could swap-out the CV diaphragm cap fasteners too, in-fact, bring one of each, and swap 'em all out!
 

Fire-medic

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Holy crap! I've just realised that you live in Miami! Don't know how I didn't realize that sooner with that detailed response. Well, I feel dumb. I live in Kendall, so that ace hardware is definitely close by me.
Here's a shot of the wall of hardware. They have a lot of stainless steel metric fasteners. Too-bad about the COVID-19 epidemic. I'm not spending any time socializing outside the house, and it wasn't until this past week that we allowed family to see us, since mid-March, and we still try to maintain separation. I wear a mask if I'm outside at the store shopping for food, and I try not to be outside unless I have-to.

There is a Fastenal store on LeJeune Rd in-front of the Miami International Airport, I go there for stuff I need to order in quantity, or specialized hardware.
3977 NW 25 St.
Miami FL 33142

If you've never been to this store, by I-595 and the FL Turnpike, the Davie Rd exit off I-595 (you can only go south) check it out. They have a lot of tools of all-types. Mechanics hand tools, power hand tools, corded and cordless, woodworking and metalworking floor free-standing tools, lathes, mills, and hardware for them. Lots of tools! Check-out their website.
International Tool
2590 Davie Rd.
Davie FL 33314
(954) 792-4403

Ace Hardware 6448 US-1 S. Miami.jpg

Here's a shot of the International Tool display for their Milwaukee hand power tools.

International Tool Davie FL.jpg
 
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Demonsinmysemen

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This is incredibly helpful, thank you.
I often feel as if going to places like Home Depot and Lowe's is just too much of a generalisation. This store near MIA is exactly what I need. For me at least, it's difficult to get anything for the Vmax without having to order online for exact parts. I could never really try them on and quickly return them if need be.

As far as this pandemic goes; about the same on my end. I just recently started venturing out a bit more. I probably could have had the bike running, if I wasn't so worried. Feeling more up to the task now. Anywho, once again, thanks a lot. I feel the Vmax community is nothing but helpful.

Hopefully this ends sooner than later. I would kill for some better expertise, if you would be up for it. Thanks, dude.

Here's a shot of the wall of hardware. They have a lot of stainless steel metric fasteners. Too-bad about the COVID-19 epidemic. I'm not spending any time socializing outside the house, and it wasn't until this past week that we allowed family to see us, since mid-March, and we still try to maintain separation. I wear a mask if I'm outside at the store shopping for food, and I try not to be outside unless I have-to.

There is a Fastenal store on LeJeune Rd in-front of the Miami International Airport, I go there for stuff I need to order in quantity, or specialized hardware.
3977 NW 25 St.
Miami FL 33142

If you've never been to this store, by I-595 and the FL Turnpike, the Davie Rd exit off I-595 (you can only go south) check it out. They have a lot of tools of all-types. Mechanics hand tools, power hand tools, corded and cordless, woodworking and metalworking floor free-standing tools, lathes, mills, and hardware for them. Lots of tools! Check-out their website.
International Tool
2590 Davie Rd.
Davie FL 33314
(954) 792-4403

View attachment 71540

Here's a shot of the International Tool display for their Milwaukee hand power tools.

View attachment 71542
 
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