Forum Donations
Search
VTF Google Search
 Click Here

90 xv750 AIS REMOVAL help

  • Advertisement

Post a reply

90 xv750 AIS REMOVAL help

PostAuthor: Smooth » Wed May 27, 2015 8:26 pm

I know this topic has been covered, i read the write up on this and seems pretty confusing (vacuum line attach). Im in the middle of the removal and stuck.
So i followed all the steps:
1. Remove the left cover
2. Remove 3 screws and detach hoses
3. Remove AIS unit
4. Disconnect petcock line from the "T" connection on smaller hose (vacuum line)
5. Stuck not clear on this part skipped to the next step.
6. Removed 2 chrome lines headed to engine. (Needs to be capped?)

Questions:
1. do i remove the calm air tubes? (The two large hoses to rear of carb)
2. Where does the small hose from the petcock (disconnected from "T") go?
3. where does the other part of that small hose connect to?

Sorry in advanced if these questions reek of noob, im coming from a streetbike so this is all alien to me.
You do not have the required permissions to view the files attached to this post.

Smooth
Junior Membership
Junior Membership
 
Posts: 59
Images: 3
Joined: Tue May 26, 2015 9:09 pm
Location: Long island, N.Y. Flag
Bike year & model: 2003 kawasaki z1000 heavily customized
1990 yamaha xv750
Sex: Male

Re: 90 xv750 AIS REMOVAL help

PostAuthor: bstig60 » Wed May 27, 2015 8:41 pm

The small hose going to the AIS needs to be removed and plugged. You can remove it at the T fitting and plug it there with a cap made for the purpose. Then remove the metal lines going from the AIS to each cylinders exhaust port. Leave the gasket in place and get two copper water pipe 1/2 inch and cap the ports using the original clamp that was there. Reinstall the left side bug eye and your done.
Bill
"It´s a friggen motorcycle, it´s not supposed to be comfortable, quiet or safe. The wind noise is supposed to hurt your ears, the seat should be hard and riding it should make you s**t your pants every now and then. "

Please take the time to edit your profile to show your location. City, State/Province, and Country.
It is easier to help you if we know where you are.


SERVICE MANUAL DOWNLOAD LINK
http://viragotechforum.com/viewtopic.php?f=220&t=31501#p279545

Image
User avatar
bstig60
Mod
Mod
 
Posts: 13720
Images: 38
Joined: Sun Jun 08, 2008 6:16 pm
Location: Sharpes, Florida Flag
Bike year & model: 1999 Yamaha Virago XV1100LC Cruiser,
2003 Honda Goldwing GL1800 Touring
2007 Honda ST1300A
1987 Honda TLR200
Sex: Male

Re: 90 xv750 AIS REMOVAL help

PostAuthor: Smooth » Wed May 27, 2015 9:25 pm

Thanks for the help. Got the vacuum line removed. What about the one from the petcock? Is it supposed to connect to something?
You do not have the required permissions to view the files attached to this post.

Smooth
Junior Membership
Junior Membership
 
Posts: 59
Images: 3
Joined: Tue May 26, 2015 9:09 pm
Location: Long island, N.Y. Flag
Bike year & model: 2003 kawasaki z1000 heavily customized
1990 yamaha xv750
Sex: Male

Re: 90 xv750 AIS REMOVAL help

PostAuthor: bstig60 » Wed May 27, 2015 9:53 pm

The vacuum line from the petcock connects to the rear vacuum port on the rear carb holder.. If your carbs have coasting enricheners they can connect to one of the vacuum ports on the front carb holder. Otherwise those should be plugged.
Bill
"It´s a friggen motorcycle, it´s not supposed to be comfortable, quiet or safe. The wind noise is supposed to hurt your ears, the seat should be hard and riding it should make you s**t your pants every now and then. "

Please take the time to edit your profile to show your location. City, State/Province, and Country.
It is easier to help you if we know where you are.


SERVICE MANUAL DOWNLOAD LINK
http://viragotechforum.com/viewtopic.php?f=220&t=31501#p279545

Image
User avatar
bstig60
Mod
Mod
 
Posts: 13720
Images: 38
Joined: Sun Jun 08, 2008 6:16 pm
Location: Sharpes, Florida Flag
Bike year & model: 1999 Yamaha Virago XV1100LC Cruiser,
2003 Honda Goldwing GL1800 Touring
2007 Honda ST1300A
1987 Honda TLR200
Sex: Male

Re: 90 xv750 AIS REMOVAL help

PostAuthor: Smooth » Thu May 28, 2015 7:01 am

Ok, before i start i think this thread will be extremely helpful to all who come across the same problems bc the detailed pics. It seems most AIS removals posted discuss 81'+ 82' and i think i seen one for a 97'. The difference is the front carb holder on the 90 does not have 2 vac ports just 1 (see attached pic).

- i looked at the carb and it seems that it does have an enricher on it(left side if sitting on bike).
- the rear carb holder (left side if sitting on bike) seems to already be plugged.
- front carb holder only has 1 vacuum port (which I disconnected the small hose with the "T" from). I understand this port has to be capped.

My question:
Understanding that the line from the petcock (previously mentioned) has to connect to the rear carb holder and the only port on the carb holder is already capped, do i remove that cap and connect the hose from the petcock there?
You do not have the required permissions to view the files attached to this post.

Smooth
Junior Membership
Junior Membership
 
Posts: 59
Images: 3
Joined: Tue May 26, 2015 9:09 pm
Location: Long island, N.Y. Flag
Bike year & model: 2003 kawasaki z1000 heavily customized
1990 yamaha xv750
Sex: Male

Re: 90 xv750 AIS REMOVAL help

PostAuthor: bstig60 » Thu May 28, 2015 10:24 am

Some models have two vacuum ports on the rear carb hold and some on the front, it doesn't matter which carb holder your vacuum line from the petcock goes to. I just used the rear one because it is the closest to the petcock. So, on your model, you need a vacuum iine to each coasting enrichener and to the petcock. They can go to the same vacuum port if you wish. All other vacuum ports not used should be plugged.
Bill
"It´s a friggen motorcycle, it´s not supposed to be comfortable, quiet or safe. The wind noise is supposed to hurt your ears, the seat should be hard and riding it should make you s**t your pants every now and then. "

Please take the time to edit your profile to show your location. City, State/Province, and Country.
It is easier to help you if we know where you are.


SERVICE MANUAL DOWNLOAD LINK
http://viragotechforum.com/viewtopic.php?f=220&t=31501#p279545

Image
User avatar
bstig60
Mod
Mod
 
Posts: 13720
Images: 38
Joined: Sun Jun 08, 2008 6:16 pm
Location: Sharpes, Florida Flag
Bike year & model: 1999 Yamaha Virago XV1100LC Cruiser,
2003 Honda Goldwing GL1800 Touring
2007 Honda ST1300A
1987 Honda TLR200
Sex: Male

Re: 90 xv750 AIS REMOVAL help

PostAuthor: Smooth » Thu May 28, 2015 1:15 pm

Thanks bill Your info has been extremely helpful. When i get in from work i will be removing that plug from the rear and use it for the front (if its the same size; should be). Plug the petcock line to the rear and trim the diaphragm hoses a bit to keep them from sticking out in the wind.

Next step on the road to Bobb:
-7/8 handlebars going to try drags or zbars.
i.) just thought about converting to single cable throttle (i have check the search bar)
-fender chop and 10" cold roll steel struts
-side mount plate & light
-reroute wiring into ammo box under seat.
-paint rims
-single headlamp with turn signals built in.

Smooth
Junior Membership
Junior Membership
 
Posts: 59
Images: 3
Joined: Tue May 26, 2015 9:09 pm
Location: Long island, N.Y. Flag
Bike year & model: 2003 kawasaki z1000 heavily customized
1990 yamaha xv750
Sex: Male

Re: 90 xv750 AIS REMOVAL help

PostAuthor: Smooth » Thu May 28, 2015 8:48 pm

Just realized you said both carb enrichers need vacuum. So i have to remove that plug, install a tee and run the petcock line to the front as well
You do not have the required permissions to view the files attached to this post.

Smooth
Junior Membership
Junior Membership
 
Posts: 59
Images: 3
Joined: Tue May 26, 2015 9:09 pm
Location: Long island, N.Y. Flag
Bike year & model: 2003 kawasaki z1000 heavily customized
1990 yamaha xv750
Sex: Male

Re: 90 xv750 AIS REMOVAL help

PostAuthor: Medina » Mon Aug 03, 2015 9:11 pm

SO, at the risk of being labeled a Jimmy Carter Lover..what gains (real world) can be had doing this?
What happens to MPG, overall performance?
I'm assuming this allows it to run richer at all speeds, any tweaking done to valve setup, carb sync, plug gap?
If this is a bandwidth wide enrichment, why bother with the off idle enrichening system? Why not cap that as well? Anyone run it with out? lean popping on decel etc?

coincidentally I was eyeballing the manual and the mysterious left side of my 93 1100 today thinking of bypassing it...if for no other reason than..you know..I can.

thanks in advance...I am simply unable to leave things alone

Medina
Junior Membership
Junior Membership
 
Posts: 8
Joined: Sat Aug 01, 2015 2:49 pm
  Flag
Bike year & model: 1993 Virago 1100

Is it Vah-rah-goe, or Vi-ray-goe?
Sex: Male

Re: 90 xv750 AIS REMOVAL help

PostAuthor: LongRoadHome » Tue Aug 04, 2015 2:51 am

No relation of MPG to AIS (Air Induction System), AFAIK. It only adds extra air to the exhaust ports after combustion. Or in other words, affects only the exhaust outside of the engine cylinders. Although I guess you could argue that it might help MPG in some way, but I have no facts about that.

The OP's AIS removal looks right to me, aside from talk of the coasting enricheners. I don't know of any vacuum lines used for them on the later model XV750's and XV1100's.
Don't confuse the fuel vent hoses with that anyhow. I think you only need the singular vacuum connection to petcock, no T's involved, without AIS there to connect to.
ImageImage
Past bikes: 1965 Honda S90; 1975 Yamaha RS100; 1981 Yamaha XS400 Special II
ImageImageImage
User avatar
LongRoadHome
Silver Membership
Silver Membership
 
Posts: 1675
Images: 7
Joined: Fri Sep 16, 2011 2:48 am
Location: Huntsville, AL Flag
Bike year & model: 1997 XV750J1 Virago
Riding 27500 miles, 42 months;
Baffleless mufflers, capped ends;
Mustang seat, zippered XL saddlebags;
Slipstreamer Enterprise windshield;
Chrome front fender, fork brace;
Progressive Springs.
Strobing LED brake light, LED gauges IC;
Pirelli Route MT66 tires.
Sex: Male

Re: 90 xv750 AIS REMOVAL help

PostAuthor: Medina » Wed Aug 05, 2015 6:17 am

Couldn't really find virago specific answers on the net, did quite a bit of digging (expanded to non yam related research) and..it seems...the ONLY benefit I can find is more accurate dyno readings.

couple of race bike forums with access to dyno's said no benefit outside it 'looks cleaner' and dyno results 'seemed' to be more stable, easier to 'tune' the bike while hooked up to a dyno, but no actual benefits...dammit....
... seems our bikes it puffs some air in every 3rd 4th cycle into the exhaust to help cheat emmisions.
which...if you think about its not really helping. exhaust badness isn't eliminated by diluting it...so...having it on is a waste, and removing it is of no benefit...YAY GOVERNMENT

Maybe, possibly in my twisted mind, it might be easier to sync the carbs without it?
...but...I just did that yesterday, a HELLA lot faster than it took me on the goldwing...didn't even pull the tank, everything was easy to get at.

Medina
Junior Membership
Junior Membership
 
Posts: 8
Joined: Sat Aug 01, 2015 2:49 pm
  Flag
Bike year & model: 1993 Virago 1100

Is it Vah-rah-goe, or Vi-ray-goe?
Sex: Male

Re: 90 xv750 AIS REMOVAL help

PostAuthor: bstig60 » Wed Aug 05, 2015 10:22 am

Yeah, the AIS doesn't do much. However removing it eliminates the possibility of a vacuum leak from it.
Bill
"It´s a friggen motorcycle, it´s not supposed to be comfortable, quiet or safe. The wind noise is supposed to hurt your ears, the seat should be hard and riding it should make you s**t your pants every now and then. "

Please take the time to edit your profile to show your location. City, State/Province, and Country.
It is easier to help you if we know where you are.


SERVICE MANUAL DOWNLOAD LINK
http://viragotechforum.com/viewtopic.php?f=220&t=31501#p279545

Image
User avatar
bstig60
Mod
Mod
 
Posts: 13720
Images: 38
Joined: Sun Jun 08, 2008 6:16 pm
Location: Sharpes, Florida Flag
Bike year & model: 1999 Yamaha Virago XV1100LC Cruiser,
2003 Honda Goldwing GL1800 Touring
2007 Honda ST1300A
1987 Honda TLR200
Sex: Male



Post a reply


  • Advertisement

Return to Yamaha Virago XV750

Who is online

Registered users: No registered users

cron