Where does this hose go?
 

Long time since I posted about this, so a recap -

XT600E 1995. I replaced exhaust headers with Motads s/s, cleaned up the cylinder head and renewed the carb mounting rubbers, after a lot of trouble with backfiring. Backfiring cured, but it's not running quite right yet. More reluctant to start, hard to get a steady idle, and when it's warmed up, the idle is way too high. If I turn the idle speed down, it won't idle at all when cold. Running at speed is fine, no power loss, all good.

Air leak was my first thought, but a check with a propane torch (unlit) arounf the inlets gave nothing unusual. I've dismantled the airbox and taken the carbs off to have a look. Here's the issue:

Coming from the top of the right-hand carb, just below the flange, is a tube with a thick black breather pipe. This is about 8"/200mm long and ends in a black plastic plug which looks like it ought to be fitted into somewhere. The natural routing of the pipe is back towards the top of the airbox. I realise now that when I put it all back together before, I must have missed this, and it has been dangling in fresh air between the airbox and shock. I'm wondering if this might be the cause of the poor idling. I know it's the wrong carb, but ...

The outlet and pipe aren't shown on the diagram in the manual I have, and I can't find anything on the web either. In fact, I have never seen one on a CV carb before, now I think of it. With the airbox loosened and moved back, I can't see anywhere obvious it would fit. (And it must have been fitted into something, as the end of it is clean and new-looking, whereas the middle bit of the plastic plug has road dirt.) I'm looking for a hole about 10mm wide, but I can't find one.

Any ideas?

Quick suggestions would be great, as she is in bits at the moment and I have to get to work tomorrow!

Thanks all.

I suspect (guess) that you may well find it goes into the bottom of the airbox to scavenge oil kicked up the crank case breather hose.

Thanks, but I doubt that. The pipe doesn't smell oily, and there's plenty in the bottom of the airbox if that were what it was for. The pipe wouldn't reach to the bottom of the airbox in any case, and there are no joints or unions there for it to fit to. It might reach the top or front (engine side) face, but again, no signs of a matching hole :(

Thanks anyway.

:stupid: What he said...

And what I said ... :)

There's nowhere that I can see for it to go on the airbox. Does anyone have a 94/95 600 who could pop out and have a look? I only want to know where the damn thing goes!

Cheers Tom.

ill nip out to the garage and have a look for you...back in a bit!

just been out and had a look. The pipe in your pic connects to another pipe that comes out from the engine between the rear of the cylinder head and the starter motor, not sure exactly what it is but took a quick photo.
http://img.photobucket.com/albums/v6...3/DSCN1353.jpg

If you need anything else checking then let me know.

Judging from that pic I'd say it connects directly with the crank case breather:eek3:. (Probably a legacy from Californian pollution laws.)

Elv, that is really helpful, and thank you. The pipe you mention, on mine, comes from the area between the cylinder base and the starter motor and fits onto a stub at the front of the airbox, about 50mm above the crankcase breather where the oil comes from. It seems like it's meant to be there, and attaching it to the carb breather pipe would involve a lot of awkward bends, so I think that's unlikely to be the correct layout, although the diameter of the pipe and the plastic plug is right.

Too dark to work now, so I'll have another look tomorrow. Thanks again, much appreciated.

hmm now youve got me wondering if mine is connected up properly:confused1:

i think i have the same pipe on a 03 model.i dont know were it goes but i have just done 23000 miles with it as it is in the photo:confused1:

I think that is just the vent for the CV diaphragm. :confused1:

Well it is for the TTR600RE.

Mine (2003) doesn't connect to anything, and im pretty sure its right that way.

Mine hangs down between the carb inlet rubbers, behind the cylinder.

Trough that hose you bring atmospheric pressure into secondary carb. Just leave it under seat.

Hehe, that might explain why I can't find anywhere for it to go into - it's design is to just 'hang down'!

As the CV is the main carb for fast running, and the fast running is fine, I thought this might be a bit of a long shot for the idle problem, but when you've got something you can't explain and there is something out of order, you do tend to link the two :)

Ah well - I'll put it all back together tomorrow and see how it goes.

Thanks to all for your inputs, especially Elv, who braved the January weather to take a photo for me. And Elv - if it runs OK, it's OK!

Hi.

I asked the same thing recently ( TT600RE).


This is the pic I posted. On my TT (not XT) it connects to nothing, and that is normal.


http://i697.photobucket.com/albums/v...pipe_small.jpg

Apart from a different dangle-angle, that's the same as mine, even down to the road muck on the barrel of the plastic plug and the clean end.

Thanks - looks like mine will have to wave in the breeze :)

hi there i have done a lot of work on a jap spec srx 600 , vertualy the same engine as a 600e and as pigford says it is just a vent for the carb , on a srx it sits at the side of the air box and do,s not connect to anything . zigzag

No problem at all,
it does seem to run fine with it connected that way (still not sure why it was like that in the first place now) but i think ill disconnect it and put it back to how it should be as per everyone elses comments and see if it makes any difference!

If you do, the pipe from the crankcase goes onto the stub on the front/right of the airbox, just above the crankcase breather (smaller pipe from same area, fits onto an elbow).

Thanks Richard, im going to go out and have a look at it tomorrow. Good luck with getting your idling issue sorted.

Thanks Elv. It's all back together and sounding OK, so tomorrow's commute will show whether it's any better.

that is actually called an airvent so as what others have said, it just hangs there. just make sure it hangs down and not pointed upward

Hi all

Well, it's all back together, with the dangly bit dangling like it should. The strange thing is that the problems I have had since the top end refurb have gone. Starting is on the button again, engine braking is fully restored, and it idles like it should, hot or cold.

Looks like taking the carbs off their stubs and re-fitting has done the trick.

Now to sort the front brake, which has become very 'wooden' and lacking in feel and power. I have a caliper rebuild kit coming from David Lambeth which should do the trick. Just cleaning the pistons with brake cleaner and a toothbrush at the weekend made them worse not better :( The Gold Fren pads don't help, as they perform much worse than the badly-worn OE pads that I took off. New pads too, I think.

Sounds like the carbs were maybe not seated quite right and you were getting air in through the carb rubbers, glad youve got it sorted now:thumbup1:

That's the only explanation, although I thought I had been very careful putting them back on, and it was the first thing I checked. Even blowing some propane around there while it was idling didn't show any leaks.

Ah well, you live and (sometimes) learn.