I don't have any photos, but I do remember there was a metal tube which connected the two carbs above the float bowl level.
I need to clean my carb, if you can wait till the Monday after next, I can do some sort of pictorial tear down/reassembly post if you think it'll help.
I need to take mine completely apart and clean it anyway since it's been two years and I must have left the fuel on over the winter when I stored it.

Smacaroni, on 04 May 2012 - 08:27 AM, said:

That would certainly help, thanks!

Yea, I noticed that. It's funny how they describe it as a fuel pipe and it sits where it does. I wouldn't think there would be any actual flow of fuel but perhaps a fuel  air mixture. I looked at the hole in the carbs that the pipe connects and it's tiny. Seems smaller than the bore of the pipe. The balancer pipe at the front looks OK but is sort of sticky like rubber gets when it's on the way out. I can get a new one for 3 euros.

Will do, Monday after next. I'm hoping I don't have English weather the Sunday after this one.

Smacaroni, on 04 May 2012 - 08:42 AM, said:

Touche! I'm a junior baseball coach and we've been rained out 3 times in a row now.

I thought you guys played Cricket? Learn something new every day. I had no idea there was interest in kids playing baseball in the UK.

Smacaroni, on 04 May 2012 - 09:24 AM, said:

Getting bigger every year!

I had a ggod look at the carb again and have some more info. I checked out the pipe network going to and from the little fuel pipe with the 2 O rings and found out that the feed from the primary carb which used to have a #48 jet is now blanked off with a blanking screw. That means there is no fuel being supplied via the pipe so it all points towards a modification of a J carb to make it work like a K carb. Not a problem, at least now I know whats going on. I put a copper washer on the elbow connector to try and achieve a better mating between the connector and the carb and put spring clips on the fuel pipe and routed a bit different so it now goes up all the time instead of down and up as before. Obviously, the hole in the nozzle is still bigger than needed but I am trying to get things back the way they were so I can ride it tomorrow. My son is doing his CBT and he wants to go for a ride after so that is the aim.

here is a pic of the new washer.


This is a pic of the nozzle from in between the carbs and according to the parts list an air breather tube is connected to this. Can someone please have a look and see where this breather pipe goes as mine has no pipe.


Of course, riding it tomorrow is completely dependant on the float chamber seal holding out as I could not put it back. I laid it on the flat side and screwed the 2 together hoping that it will form a seal of some kind. Here's hoping !

Edited by pete63, 05 May 2012 - 03:42 AM.

You could cut a gasket from a cereal box ... Use the bowl as a template . Smear a thin coat of oil on the mating surface before you lay the bowl on the inside of the cardboard . This will give you a fair outline of where to cut . Once cut , leave the o ring gasket in place and add the 'paper' gasket .

Go have fun with your boy .

pd350, on 05 May 2012 - 05:09 AM, said:

Yea, I read that on the web. In the end I got some fuel resistant gasket sealant and fitted the old gasket using the sealant as a holding agent. That bit seems to work however my copper washer solution leaked like a sieve so I had to fit an O ring with some gasket sealant on and it's currently sitting in the garden. I'll have a look in a few minutes and see if it's still leaking. If not, it's skinned knuckle time trying to refit the carb.

Edited by pete63, 05 May 2012 - 07:05 AM.

That o ring will likely squash out of place and leak .

You might try some pipe thread tape on that elbow . Or , maybe just a helping of that fuel resistant gasket sealant on the threads of the elbow might seal it .

pd350, on 05 May 2012 - 07:17 AM, said:

Yea, I used the sealant and the O ring did pop out but it seems to be holding. Put it back on the bike with only one skinned knuckle and was a bit of a bitch to start but I put that down to the inlets being open and the carb a bit messed up but eventually it settled down. Seemed to not tick over like it did, I had to adjust the idle screw and now it idles at around 1400 rpm. I'll adjust it back once I've taken it for a thrash. I'm just wondering if I've upset the float in some way or some debris have got in there. Anyways, it runs, BUT, it sounds different. Can't explain in what way, not so "tinny" if you get my drift. I'll take it out for a thrash later and see what happens but it's looking like I'll get that ride in tomorrow which in my book is mission accomplished.

Round 2 begins if I win that carb on ebay.de.

One thing that really pissed me off. When I was putting the tank back on the handlebar swung round and put a big scratch in it. Seriously pissed off but that can sorted easily. Just more money.

Edited by pete63, 05 May 2012 - 08:14 AM.

"the handlebar swung round and put a big scratch in it."

Now you can tell it from all the other XT550s in the neighborhood .

Took it for a spin and it's still the same. I think the answer is probably the later carb as it seems to be a lot better. Unless of course the problem is something else like ignition or something? If it was ignition, wouldn't it show up when you rev it in neutral?

pete63, on 05 May 2012 - 08:12 AM, said:

This adds character.
My tank has a big dent in the one side and a hunk of rust on the other. That's 30 years of character. Could be much worse.

As far as putting the carbs in and out, under the seat are two bolts that run through plates on the frame between the tank and CDI that don't really look like they do anything.
Loosen those two and a third bolt on the left hand side to make the air box mobile. This will make removing and reinstalling the carbs slightly less painful. Like the difference between having a root canal and a tooth extraction without Novocaine. In both cases, after the local yob bruised your face up real good, with a hammer. The claw end of the hammer.

pete63, on 06 May 2012 - 09:20 AM, said:

In my case, the ignition problem only appeared above 4,000 RPM regardless of throttle position and once warm (hot really) it was fine. It didn't behave any differently from normal when in neutral.
I doubt that revving it in neutral can give you any diagnosis of any problem unless it is severe.

If I haven't mentioned it before , you might reposition the magneto pick up as close to the wheel as possible without making any contact . If it's too far away , it can cause erratic performance in mid range and above RPMs . I have my pick up set at .012" .  The tighter the gap , the more defined ( better ) the resulting spark .

Smacaroni, on 07 May 2012 - 11:51 AM, said:

When the problem arises,if you accelerate gently on my bike, it sort of gradually increases in speed but doesn't really get past 60. It feels tbe same as when you run out of fuel and have to switch to reserve but more drawn out. Does that sound like ignition?

pd350, on 07 May 2012 - 04:16 PM, said:

Sounds like something I could check. How do I get to it? Is it behind the left hand crank case cover?

Edited by pete63, 08 May 2012 - 12:37 PM.

pete63, on 02 May 2012 - 06:53 AM, said:

5.32 pounds for the float chamber gasket:

http://www.wemoto.co...at_bowl_gasket/


Regarding the CDI, it is hard to tell if they are faulty or not.  I have had two fail on my 550.  The first one made the bike very hard to start but the bike ran good once started.  The other one did cut out at maybe 3000 rpm's, but the bike started fine and ran good from idle to maybe 2000 rpm's.

If you have any chance of borrowing a CDI you should.

Correct , the magneto pick up is behind the left hand crank case cover .

pete63, on 08 May 2012 - 12:35 PM, said:

Worry about the carb first. That's so bollocks with the pipe nipple "jet" it's not even worth looking at electrical problems IMHO.

ALWAYS check the easiest things first .

Smacaroni, on 09 May 2012 - 03:56 AM, said:

Yea, I agree. Trouble is, I have nothing to compare the current elbow connector thread to. These bikes are so rare over here and tbh, the British nature wouldn't allow for someone to dismatle anything to let you see. If I win the 5Y3 carb (which is a definite K model), I can compare the thread. If I find that they are the same (which would surprise me) I can buy the bits to fit.

pd350, on 09 May 2012 - 04:37 AM, said:

Yep, I'll do that as and when it stops raining. We are in the middle of a drought over here so it should stop raining soon.

Edited by pete63, 09 May 2012 - 11:38 AM.