Forum Donations
Search
VTF Google Search
 Click Here

New 535 owner with carb issues

  • Advertisement

Post a reply

New 535 owner with carb issues

PostAuthor: 79Thunder » Fri Jul 26, 2019 12:54 am

Hi guys, great forum. I have already found a great deal of information here already.

I just picked an '87 535 for my son. I've gone through it from stem to stern and one of the last orders of business is some carb issues.
The bike starts and runs quite well honestly..but at idle and light part throttle it pops through the exhaust and surges.

I have cleaned out the main and pilot jets and passages very well. (carb cleaner and compressed air).
Everything was surprisingly clean. No improvement in how the bike ran.

My next goal was to try to adjust the idle mixture screws.
The plugs had already been removed.
The mixture screw on the front carb was bottomed out and was very tight.
The mixture screw on the rear carb is fubar!
There is no slot for a screwdriver. (maybe the p.o. drilled too deep removing the cap ?)

I obviously need to remedy this, but, I guess the question is, why does this bike run as well as it does??

Where should I look for other modifications or compensation?
Is it as simple as an over adjusted idle speed screw and it's pulling fuel from the mains?

I'm thinking I'll have to get some new mixture screws coming and I'll have to drill and use an easy out on the really bad one.

.
Last edited by 79Thunder on Fri Jul 26, 2019 1:28 am, edited 1 time in total.

79Thunder
Junior Membership
Junior Membership
 
Posts: 4
Joined: Thu Jul 25, 2019 11:40 pm
  Flag
Bike year & model: 1987 535 Virago
Sex: Male

Re: New 535 owner with carb issues

PostAuthor: Flyingdog » Fri Jul 26, 2019 1:18 am

:VTF:

Yep..getting the carbs parts back to working OEM, "mechanically", would be a good start, before any changes. Very well could be the popp'n/hick-ups. Even though it idles ok..could be starving for fuel..off idle. Kinda a toughy at this point.
User avatar
Flyingdog
Silver Membership
Silver Membership
 
Posts: 2866
Joined: Fri Jun 23, 2017 2:31 am
Location: Colorado Flag
Bike year & model: 1985 xv1000 Virago
1981 xv750 Virago
Sex: Male

Re: New 535 owner with carb issues

PostAuthor: 79Thunder » Fri Jul 26, 2019 1:32 am

That's why it's a little tough for me to wrap my head around it.

At idle it smells too rich.
At part throttle/cruise it sure seems like a lean surge.
(makes sense if the pilot screws are bottomed out and not adding additional fuel)

79Thunder
Junior Membership
Junior Membership
 
Posts: 4
Joined: Thu Jul 25, 2019 11:40 pm
  Flag
Bike year & model: 1987 535 Virago
Sex: Male

Re: New 535 owner with carb issues

PostAuthor: bstig60 » Sat Jul 27, 2019 7:01 am

Pilot screws should be set at 2.5 turns out from a soft seat as this is near the factory setting. They can be adjusted from there as needed. Check your float settings, There is a gauge built into the carbs.
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: 13474
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: New 535 owner with carb issues

PostAuthor: 79Thunder » Sat Jul 27, 2019 7:39 pm

bstig60 wrote:Pilot screws should be set at 2.5 turns out from a soft seat as this is near the factory setting. They can be adjusted from there as needed. Check your float settings, There is a gauge built into the carbs.



I'll adjust the pilot screws when I get them broken free and replaced.
I do have the front one out, but I'm afraid I'm going to have to drill the rear one.

New pilot screws on order.
The floats have already been checked/adjusted.

Thanks!

79Thunder
Junior Membership
Junior Membership
 
Posts: 4
Joined: Thu Jul 25, 2019 11:40 pm
  Flag
Bike year & model: 1987 535 Virago
Sex: Male



Post a reply


  • Advertisement

Return to Yamaha Virago XV535

Who is online

Registered users: No registered users