Finally picked up an XS400...

[Myke Nytemare]

So after messing around on here and picking some brains, I finally picked up an XS400 in good condition (some disassembly) at 9am today with the help of a strong friend who has a pickup. .

After a full day with my buddy, it's together but not running as the carb is likely completely gunked up. Was hoping it would magically just run...wishful thinking. The rear caliper appears to be sticky (flush and rebuild of reservoir/caliper probably fix it).

I'm going to sonic clean and freshen up the carbs with a rebuild and sync(may be a while as I'm only off a day or two a month).

*Anyone have carb rebuild kit suggestions (any alcohol/ethanol resistant gaskets out there)?
*Any places to get rear disc caliper seals and fluid reservoir rebuild pieces? Any parts from 650s work?

 

[BBS360]

*Anyone have carb rebuild kit suggestions (any alcohol/ethanol resistant gaskets out there)?

Honestly, carb rebuilding is probably the most covered subject on the forum. Lots of info on rebuild kits. Mostly advice to stay away from them.
I'd order genuine Mikuni jets if you need them. New float needle valves might be a good idea. All depends on the condition of the carbs.
As for ethanol, there's not much available that's resistant. Run ethanol-free if you can.

I was able to track down ethanol resistant viton butterfly shaft seals for both my bikes. Needed them anyways and they weren't any more than OEM.
Now I have NOT run them in any engine but I was so impressed at how well they fit in my 360's carbs, MUCH better than certain aftermarket seals, that I ordered another two sets right away, one for my 400 and one backup. Will hopefully be firing up both bikes soon.
If you want them you'll have to email LiteTek directly.
The butterfly shaft seals are the TS-001s:
http://litetek.co/Carb_Kit_Yamaha_FZR750.html
I'd get the "SC-002" screws listed there two. You'll need four seals and four screws to rebuild a set of carbs.
I think my first order totalled $16 Canadian, including shipping. Took slightly over a week to get here.

That all being said, OEM seals are still available directly from Yamaha and they obviously work very well for just about everyone.

*Any places to get rear disc caliper seals and fluid reservoir rebuild pieces? Any parts from 650s work? View attachment 26321

For the caliper, yes and yes:
http://www.partzilla.com/parts/detail/yamaha/YP-1J3-W0047-00-00.html
http://www.partzilla.com/parts/sear...977/XS400D/REAR+DISC+BRAKE-CALIPER/parts.html

As for the rear master cylinder, it's come up before and nobody has been able to find rebuild kits. If it needs to be cleaned, do it carefully and you might be ok.
Apparently it does take the same rebuild kit as that year's SR500:
http://www.partzilla.com/parts/detail/yamaha/YP-1U4-W0042-50-00.html
And these guys seem to think they've found some parts:
http://241-65.hostmonster.com/forum/viewtopic.php?t=13738&p=96972
Of course they didn't follow up to say whether it worked.

 

[Myke Nytemare]

BBS360, Thank you yet again for the info.

 

[Myke Nytemare]

So I removed the carbs and being that I have spark and air, I have to redo them. Bought 2 Keyster kits and will be running the carbs through several cycles in a heated sonic cleaning machine in the next week or two before I begin rebuilding.

Anyone have any suggestions for refinishing the carb body before reassembly? I know some places do a new zinc type coating...opinions?

 

[Myke Nytemare]

Interesting to have green residue in just one carb...

 

[xschris]

When bikes are put up for long amounts of time they end up left on their side stands. All the gas goes to that side carb and causes all the damage. I have seen a lot of sets with that carb destroyed because of it. People need to store the bike on the center stand!!

 

[Sesty]

makes sure those floats....well float...

Mine didnt look nearly that corroded and still had a small leak on one of the seams

 

[Myke Nytemare]

Caught a break, they float

.... Ditching the sonic cleaning and will do the "lemon juice boil, dish soap scrub, dry, wd40/machine oil scrub" process in the next few days while I wait for the rebuild kits.

 

[drewpy]

hold them under water and see if you get bubbles rising

 

[Myke Nytemare]

hold them under water and see if you get bubbles rising

I did for 2 minutes and nothing!

 

[Sesty]

give them a shake if dont hear any fluid you should be good!

 

[Sesty]

and is your avatar a picture of a porkroll and cheese sandwich?... god i am hungry...

 

[Myke Nytemare]

and is your avatar a picture of a porkroll and cheese sandwich?... god i am hungry...

SESTY....Its just some fresh uncured german smoked bacon. I took a pic for a friend and they drooled over it...when it is viewed in 4K with the up close focus, it is life changing

Also, wondering if I should disassemble the butterflies and the choke plungers before cleaning the carbs?

 

[Sesty]

yes on the plungers... if boiling or ultrasonic cleaning then yes to both.

careful not to lose the tiny balls which rest in the dents on the choke rod... they are spring loaded and will get lost

 

[Myke Nytemare]

thanks for the info...saw them on the sheet I have on the workbench and was wondering if thats where they went...never worked on a dual carb, manual choke setup before (lots of cable driven dual carbs or simple single carb bikes)

Hopefully get them all cleaned and reassembled in the next few days and maybe the bike will at least fire up and run in some capacity.

 

[BBS360]

Unless the butterfly shaft seals are in pristine condition you'll probably want to replace them anyways. Better to do it now while everything is apart than to discover a vacuum leak down the road.

 

[BBS360]

Apparently the springs from inside inner tube valves can replace the choke detent springs. There's a post somewhere.

I managed to keep the ball and lose the spring. Local dealer had the balls but not the springs so I'll be cutting up an old tube soon...

 

[Myke Nytemare]

Well my wife just disturbed the work bench and now I'm down a spring (I only saw 2 Springs and 2 balls even though there are 3 detects in the rod.

Guess I may have to order a bearing and use a few inner tube springs of some sort if there was 3.. Damn :-(

 

[Sesty]

only 2 balls and 2 springs... one for each plunger...

 

[Myke Nytemare]

Definitely mangling the screws trying to get the butterflies off....waiting to hear from that Canadian company bbs360 mentioned about the new viton seals and screws. Well they are in Thailand but will ship everything for $10 US.

Cant seem to find the screws and seals on Partzilla or on the diagram, so I guess it's good they came through on the parts.

Hopefully have the carbs together and on the bike once everything arrives.