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Carb upgrade

Started by legacybrg, June 24, 2020, 07:42:44 AM

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legacybrg

Hi all, my '82 Xz has the original carb/airbox setup. Getting it to run well has been a real challenge over the last few years. Currently, idle is variable and, there is still the classic stutter rolling on power. Saying that, it's rideable and good fun. I can however obtain the OEM carb upgrade kit for a not unreasonable price. Is it worth it ?

Boomer

I found that even after install of the kit I had issues although they were not as bad. I changed out my mufflers and had a huge positive change. NOTE: The muffler swap was a conversion. Lots of work, lots of swearing, and even some blood.

legacybrg

Thanks for the advice.

fret not

By OEM carb upgrade kit are you referring to the replacement of the top of a carb?  There was a "kit" that replaced one of the carb tops.  I think you will have to go through a process of sorting your carbs.  Tiny passages in the carb bodies must be cleared of any foreign matter, then begin a step by step process of sorting them.

POD has laid out the steps to sorting the original carbs, and usually that should be sufficient.  However, there are some carbs that seem to have a mind of their own.  As you know, they are sometimes very "touchy", but should be able to be sorted. 
Some of us have resorted to transplanting other carbs to avoid the issues of the original carbs.  There is no really easy answer, one way or another you have to sort the carbs.
Retired, on the downhill slide. . . . . . . . still feels like going uphill!

MikeScoot

lolol Yep, "mind of their own" alright!
I have a spare set of carbs here but haven't yet resorted to resurrecting them - preferring to not be defeated by the ones I have cleaned and adjusted several times already.

I know it's a little off-topic but has anyone had good results (overcoming issues in looney carbs) by ultrasonically cleaning them?
Both Luthers had their dreams,
But I've just got one Vision.
Theirs got them into strifes,
Mine just takes me fishin'.

The Prophet of Doom

Quote from: legacybrg on June 24, 2020, 07:42:44 AM
Hi all, my '82 Xz has the original carb/airbox setup. Getting it to run well has been a real challenge over the last few years. Currently, idle is variable and, there is still the classic stutter rolling on power. Saying that, it's rideable and good fun. I can however obtain the OEM carb upgrade kit for a not unreasonable price. Is it worth it ?
There aren't any "kits".  It's a road to only go down if you are happy doing light fab work.
I've not done it so can't comment on whether its worth it, but There is NOTHING wrong with the 82 carbs.  Clean stock carbs with 16R/11U jetting (120F/120R air jets) work really well till you get a hole in your YICS.

If you have variable idle my guess is you have unsynced carbs, and/or an air leak.

Fret was referring to this post http://ridersofvision.net/rovforum/index.php?topic=15295.msg140316#msg140316 , But it was more aimed at modifiers who need a new jetting to compensate.   For a stock bike just clean and adjust, (and change the pilot air jets).  Ultrasonically carb cleaning is overrated - as is the need for surgical cleanliness.  Just make sure the small holes are all clear.

For all carb work you need JIS screwdrivers.   Phillips drivers will ruin the screw heads.

Rikugun

QuoteFor all carb work you need JIS screwdrivers.   Phillips drivers will ruin the screw heads.
I was watching a YouTube video not too long ago were the presenter discussed JIS vs. standard philips and mentioned the JIS standard would be discontinued at some point.  Anyone read anything about this? If it's true, the drivers may not be offered for much longer after that.  If you don't have a set, maybe now is the time.
It is far better to grasp the universe as it really is then to persist in delusion, however satisfying or reassuring.  Carl Sagan

MikeScoot

That's a bit hard to imagine. Pretty much everything of quality made by Japanese manufacturers adheres strictly to various JIS, and I haven't heard or seen anything to indicate they will abandon any aspect of them anytime imaginable.
I will, however, consult with some Japanese engineers I know.
Both Luthers had their dreams,
But I've just got one Vision.
Theirs got them into strifes,
Mine just takes me fishin'.

Walt_M.

There is nothing wrong with JIS, just use the proper tools.
Whale oil beef hooked!

injuhneer

Quote from: MikeScoot on June 25, 2020, 03:55:22 AM
lolol Yep, "mind of their own" alright!
I have a spare set of carbs here but haven't yet resorted to resurrecting them - preferring to not be defeated by the ones I have cleaned and adjusted several times already.

I know it's a little off-topic but has anyone had good results (overcoming issues in looney carbs) by ultrasonically cleaning them?

Yes.

- Mike O
1982 Yamaha XZ550RJ

injuhneer

Quote from: Prophet Of Doom on June 25, 2020, 04:49:56 AM
Quote from: legacybrg on June 24, 2020, 07:42:44 AM
Hi all, my '82 Xz has the original carb/airbox setup. Getting it to run well has been a real challenge over the last few years. Currently, idle is variable and, there is still the classic stutter rolling on power. Saying that, it's rideable and good fun. I can however obtain the OEM carb upgrade kit for a not unreasonable price. Is it worth it ?
Ultrasonically carb cleaning is overrated - as is the need for surgical cleanliness.  Just make sure the small holes are all clear.

For all carb work you need JIS screwdrivers.   Phillips drivers will ruin the screw heads.

I won't go back to manual cleaning. The ultrasonic bath I have in the shop gets used alot. If the carbs are properly suspended it does a fantastic job. Only a few shots of air needed then to clear and dry the innards.

Prior to that I used the Yamaha carb cleaner.

Now it is just hot water and a bit of Simple Green.
- Mike O
1982 Yamaha XZ550RJ

The Prophet of Doom

Quote from: injuhneer on July 27, 2020, 08:22:53 PM
If the carbs are properly suspended it does a fantastic job. Only a few shots of air needed then to clear and dry the innards.
I find the ultrasonic cleans the outside OK, but doesn't budge crusty varnish on the inside of passages. 
I like to follow up with chemicals, pipe cleaners and nylon wire before the air.

injuhneer

I suspect that most single frequency fixed wattage cleaners don't do a good job. Multiple frequencies and modes (pulse, sweep, etc) make all the difference.

I started with a small cleaner and eventually upgraded to something with the power and modes to do the job.

- Mike O
1982 Yamaha XZ550RJ

MikeScoot

Quote from: injuhneer on July 30, 2020, 01:59:58 AM
I suspect that most single frequency fixed wattage cleaners don't do a good job. Multiple frequencies and modes (pulse, sweep, etc) make all the difference.

I started with a small cleaner and eventually upgraded to something with the power and modes to do the job.

If I am able to find someone local with such a cleaner, what kind of preparation is required before handing over the carbs for cleaning?
Thanks,
Mike
Both Luthers had their dreams,
But I've just got one Vision.
Theirs got them into strifes,
Mine just takes me fishin'.

legacybrg

Hi all, just an update - upgrade kit obtained and installed. Photos attached showing parts list and kit number. 'Bike started well and after adjusting idle ticks over nicely. Ran out of time today to take it for a ride so, a proper assessment is pending. Fingers crossed, watch this space!

fret not

Always interesting what might surface as "parts available" for an obsolete model. 

JIS = Japanese Industrial Standard
Retired, on the downhill slide. . . . . . . . still feels like going uphill!

The Prophet of Doom

The kit has a replacement #135 Pilot air jet.  There was some speculation here that the replacement (front) top had a #130 installed but I suspect a #135.
Since you are the only owner of a mod kit I've ever hear of would you mind checking that?

injuhneer

It would be nice to get a full scan of the parts sheet.
- Mike O
1982 Yamaha XZ550RJ

The Prophet of Doom

Quote from: injuhneer on August 02, 2020, 12:51:05 PM
It would be nice to get a full scan of the parts sheet.


Go to the Resources topic and look for it there...


Service GuidesXZ550 (11J) Intake and Carburetor Modification Kit 1982 Models

injuhneer

Thanks.

Interesting "fix". I guess I'd have to inspect one directly to be certain but the kit looks like it adds an air bleed to one of the carb circuits.
- Mike O
1982 Yamaha XZ550RJ