Author Topic: 81 XS 1100 Start  (Read 57940 times)

0 Members and 1 Guest are viewing this topic.

Offline Miti

  • Broken..?!! Aye, that'll be right..!!
  • Administrator
  • Jr. Member
  • *****
  • Posts: 47
  • Gender: Male
    • Mitiweb
Re: 81 XS 1100 Start
« Reply #75 on: July 31, 2012, 07:59:16 AM »
I do think that this is not a tuning issue as much as a fuel flow issue. After I cleaned the carbies yesterday the motor ran, roughly but it ran. Before I cleaned and now the only way the motor will run is if I squirt fuel down the carbies. So it seems that something is not working in the way the carbies suck in the fuel...

Apart from the needle seat at the bottom of the diaphragm and the fuel mixture screw I believe I stripped everything else in the carby (not the diaphragm assembly either)

Brett, I think you're 100% correct about the fuel not getting from the float bowl to the engine and your comment that you've not had the diaphragms out tells me that you've NOT had the emulsion tubes out of the carbs...  I rebuilt a pal's carbs from his 2H9 earlier this year and here's what I found:



In the photo, the carb is upside-down and the emulsion tube has been pressed down into the venturi mouth... You can see the holes where the air/fuel mix and you can also see the band of shite that has built-up around the base of the tube, just above where the main jet screws in...

To remove the emulsion tube (assuming you've already got the float bowl off):

1.  Remove the carb top. (4 x JIS Crosshead screws)
2.  Remove the diaphragm spring
3.  Remove the diaphragm (complete with slide and needle valve assy)
4.  Remove the main jet, lift of the washer underneath and replace the main jet, leaving about 2mm between the head of the jet and the carb body casting.
5.  GENTLY (you're working with brass) tap the main jet until the head is against the carb body.  Unscrew the jet 1 turn and tap it in again...  You're tapping the emulsion tube down into the venturi mouth...
6.  Once the tube is moving freely, remove the main jet and push the emulsion tube out of its' recess.

Clean with a neutron bomb, dettol and compressed air.

NOTE:  When replacing the tube in the carb, you need to align the slot in the tube with the pin in the carb and DON'T overtighten the main jet... They snap..!! (DAMHIKT)

HTH

Miti
« Last Edit: July 31, 2012, 08:03:51 AM by Miti »
One of those terribly nice chaps on XS1100.com
Jeff Mitchell
XS1100S '81 (Sport - 5k7) - 1985
XS1100S '81 (Sport - 5k7) - 1983
XS1100LG (Midnight Special 4H3)
Hesketh V1000 - (1982 - Pre-production, post EN10)

Offline steptoe

  • Administrator
  • Hero Member
  • *****
  • Posts: 2170
  • Gender: Male
  • Geoff,, a XS addict,, Bundy QLD
    • Bikes and trucks what more could you want
Re: 81 XS 1100 Start
« Reply #74 on: July 31, 2012, 06:57:23 AM »
I,ve had the night to sleep on this little bit of a problem,and I,ve come up with a couple more things for you to check,,

1,, if you run out of things to do waiting for Aussi,s carbs to show up have a crack at this for a post repair,  you,ve nothing to lose and might even give yourself a spare set of carbs



2,, if your having to fuel it to make her run, I,m thinking you may have more of a vacuum issue rather than fuel,,

start by checking that the caps over the spigots on the intake manifolds are nice and tight, and the vac advance hose is firm

don,t remember if you have an octty on, but bypass that as it has a diapragm in it which will stop fuel flowing past it

and lastly {for the minute} :-\  it might pay to remove an intake manifold to see what the seating o-rings look like, they could be cracked thru letting xs air in allowing it run up to #$*t

I know you,ve said the externals look horrible, but the inside can still be in good condition, sometimes the casting rubber goes as hard as  and comes away from the metal flange,
will it run long enough to spray ether or some such over them or not?

another super quick fix for the manifols is simply wipe a layer of silastic over the whole manifold sealing all the cracks till you can get some new  ones, doesn,t look pretty but works a treat

Offline Eveready1100

  • Have Bike, Will Ride.
  • Hero Member
  • *****
  • Posts: 1822
  • Gender: Male
  • Childers , QLD
Re: 81 XS 1100 Start
« Reply #73 on: July 30, 2012, 10:31:12 PM »
You might've missed it as the posts are coming thick and fast at times.

Just had another thought....

Quote
The number on the vin plate which is my best guess is the frame number is 3x1003913

My details etched on my VIN plate and my bike are wrong, so there's a chance yours might be too!
Have a look at the right hand side of the headstem. The frame number is stamped there. This is the number we need for a positive ID on your bike. This'll sort it, one way or another.
Errol
1979 XS1100 SF Special
1978 XS1100E Donor
"I know stuff about stuff."

Offline BrettS

  • Hero Member
  • *****
  • Posts: 1052
  • Novice bike rider
Re: 81 XS 1100 Start
« Reply #72 on: July 30, 2012, 10:06:36 PM »
Thanks Errol yes brass floats. Mine really is a bitsa lol I guess I will gradually get my head around all the different variations.  Thanks also  Jeff I somehow missed that thread was from you mate. I am looking forward to having a chat with the museum tomorrow

Offline Eveready1100

  • Have Bike, Will Ride.
  • Hero Member
  • *****
  • Posts: 1822
  • Gender: Male
  • Childers , QLD
Re: 81 XS 1100 Start
« Reply #71 on: July 30, 2012, 08:45:20 PM »
Ahhh. I just noticed your carbs have the drain bolt in the bottom, same as mine, as opposed to having a phillips head screw and a drain spigot. While you're getting the carb bits blown out, maybe drop by a parts place and pick up a barb fitting that'll screw into where the drain bolt goes. Then hook the tube to that.

Actually, looking back at the photo of the carb rubber, those carbs look identical to mine, which are '78 vintage. They have got brass floats in them, right?
Oops, forget i asked. Just saw them in some previous photos
« Last Edit: July 30, 2012, 09:01:40 PM by Eveready1100 »
Errol
1979 XS1100 SF Special
1978 XS1100E Donor
"I know stuff about stuff."

Offline BrettS

  • Hero Member
  • *****
  • Posts: 1052
  • Novice bike rider
Re: 81 XS 1100 Start
« Reply #70 on: July 30, 2012, 08:34:21 PM »
Thanks Errol and Steptoe,
I don't think it mentioned how to attack the tube to the hole of the float housing. Thinking even one of these that I could swap from carby to carby would tell alot at the moment for my issue.
Thanks.
I will call the museum tomorrow and see if they can take some pics, Maybe take a chassi number as well. (edit:oh you did mention that)I will also give the carby's I have the once over again. One thing I don't have is compressed air. Keep telling the misses we need a compressor but it hasn't turned up yet  :P
Might head down to a shop and get it blown out.
Cheers
Brett

Offline excess.11

  • Jeff
  • Hero Member
  • *****
  • Posts: 1875
  • Gender: Male
  • Welcome to the group. Now let us know a bit about you in General Discussions and PM me your postal details so I can send you our group stickers etc.
Re: 81 XS 1100 Start
« Reply #69 on: July 30, 2012, 08:15:05 PM »
The USA models had a hazard switch on the underside of the left hand switches........the standards here....did nt.
The right hand extra switch is anyones guess.
More than likely for the police lights and or siren.
If that is the real Mc Coy police bike in the museum.............along with checking engine and frame numbers to asertain if it is........you could ask if that switch is on the display bike and what it operates.
« Last Edit: July 30, 2012, 08:28:16 PM by excess.11 »

Offline BrettS

  • Hero Member
  • *****
  • Posts: 1052
  • Novice bike rider
Re: 81 XS 1100 Start
« Reply #68 on: July 30, 2012, 08:08:30 PM »
Ah ok thanks, is the no hazard lights normal and what do you make of the extra switches on the right?

Offline Eveready1100

  • Have Bike, Will Ride.
  • Hero Member
  • *****
  • Posts: 1822
  • Gender: Male
  • Childers , QLD
Re: 81 XS 1100 Start
« Reply #67 on: July 30, 2012, 08:08:15 PM »
Not ready to tag out yet, mate.
you do your carb clean again, when you get them back up in position, with the bike on the centrestand, try setting up something similar to this to check the float levels - CLICK

Another helpful hint by Steptoe. Very useful in this instance
Errol
1979 XS1100 SF Special
1978 XS1100E Donor
"I know stuff about stuff."

Offline excess.11

  • Jeff
  • Hero Member
  • *****
  • Posts: 1875
  • Gender: Male
  • Welcome to the group. Now let us know a bit about you in General Discussions and PM me your postal details so I can send you our group stickers etc.
Re: 81 XS 1100 Start
« Reply #66 on: July 30, 2012, 08:05:03 PM »
There are about 4 or 5 different publications (mostly suited to the USA models)........the original workshop manual as used here in Australia should have it.

Offline BrettS

  • Hero Member
  • *****
  • Posts: 1052
  • Novice bike rider
Re: 81 XS 1100 Start
« Reply #65 on: July 30, 2012, 08:00:46 PM »
Oh how come it is not in the manual?

Offline excess.11

  • Jeff
  • Hero Member
  • *****
  • Posts: 1875
  • Gender: Male
  • Welcome to the group. Now let us know a bit about you in General Discussions and PM me your postal details so I can send you our group stickers etc.
Re: 81 XS 1100 Start
« Reply #64 on: July 30, 2012, 07:59:11 PM »
Brett , the extra switch on the left you noted.is actually standard .........it s to flash the high beam on your headlight.
« Last Edit: July 30, 2012, 08:25:16 PM by excess.11 »

Offline BrettS

  • Hero Member
  • *****
  • Posts: 1052
  • Novice bike rider
Re: 81 XS 1100 Start
« Reply #63 on: July 30, 2012, 07:57:36 PM »
Hey Steptoe. The guys might be just about ready for you to tag in I would have worn them out by now with all my questions LOL.
I hear what you are saying and the fuel mixture screw was about the only thing I did not remove and clean. I talked Jeff into agreeing to leave them alone as I had read and it made sense that they would most probably already be reasonably set so best not to muck with them.
I think in the condition the carbs are that may have been a mistake. The carb cleaning instructions I used from XS11.com gave instructions how to reset and I should have used them.
But in my on location wisdom I do think that this is not a tuning issue as much as a fuel flow issue. After I cleaned the carbies yesterday the motor ran, roughly but it ran. Before I cleaned and now the only way the motor will run is if I squirt fuel down the carbies. So it seems that something is not working in the way the carbies suck in the fuel. The float chambers seem to have enough fuel in them but I could be easily wrong there.
There is something very basically wrong at the moment??

Apart from the needle seat at the bottom of the diaphragm and the fuel mixture screw I believe I stripped everything else in the carby (not the diaphragm assembly either) I used loads of carby clean. Soaked all jets and then poked all holes and thourally cleaned all jets. The jets where very clogged and the small long ones needed a lot of persuasion to come out of their hole. The second clean it seemed they were a little clogged again.
I will remove the fuel mixture screw on this next clean while I wait for Bryan's sett to turn up.
Do you reckon the ones he is sending me could be an old set of the 107 HP bike LOL I wish  :D

Offline BrettS

  • Hero Member
  • *****
  • Posts: 1052
  • Novice bike rider
Re: 81 XS 1100 Start
« Reply #62 on: July 30, 2012, 07:38:00 PM »
Thanks Errol those pics are great. They do look very similar to the one I posted so I guess it was also genuine.
There is alot for me to take in I thought we figured out that it was a 81 SX11H ( I think Eddy missed a thank you for that great link  ;)) with a police motor leaving a few things unanswerd such as strange indicators and such. One I noticed was the undrilled disks which in my limited knowledge is out of place for a 81XS11H.
It seems that if this went from police bike to public bike then maybe the "bitsa" pieces was replacing the police bits.
The switch on the left handlebar does look the same. Will have to drop in to that museum one day. Hmm wonder if they could take some pics for me if I called them. Can't hurt to ask.
Thanks again Errol

Offline steptoe

  • Administrator
  • Hero Member
  • *****
  • Posts: 2170
  • Gender: Male
  • Geoff,, a XS addict,, Bundy QLD
    • Bikes and trucks what more could you want
Re: 81 XS 1100 Start
« Reply #61 on: July 30, 2012, 07:21:14 PM »
hey Brett, Geoff here mate,, I spend my life on the road in trucks so this whole thread has happened since I logged in last,,  sounds like you'll have the rocket up and running in no time with all the help the lads are loading you up with,,

one thing with the way the carbs are playing up,, while it's on the kitchen table, take the air fuel mixture screws out, the small ones on top and in front of the diaphragms,, the VERY small o-rings on the end of the screw under the spring and equally small washer,,{although it will be more than likely stuck to the bottom of the hole} could have perished and be not helping your cause in any way,, I think some one back in the thread said to check the point on them and make sure the tip isn;t snapped off,

have you drowned them with "carby clean",, get a can of this stuff and give all the small holes in the carbs a good drowning, this will help

another thing that definetly will help while putting them back together is have all four carbs as close together in measurements as possible,,have all the screws set at the same number of turns out from bottom,, {start at 1 3/4} and have all the slides set at the same hieght {off the bottom of the carb body} using anything as a measue, {a tooth pick or twist tie,, something that won't scratch the inside of the body} do this by adjusting the screws with the springs on them in between the carb bodies

I haven't read wether the enricher tubes {choke} slides are free or not, they are the slides with the 17mm nut on them they may also be hampering things,,

why it is running rough is very simply,, you have 4 motors,,  4 cylinders  and  4 carbs,, so to get it to run as 1 all carbs have to run as 1,,  so syncronising {adjusting} them as close as possible to one another is very important,, Jonesy might be able to slip over and help with that further

I'll let you play with this bit more info to process and see how you go

Geoff

« Last Edit: July 30, 2012, 07:23:21 PM by steptoe »