Jump to content

XJ550 Exhaust Issues


OrganicMuscle
This post is 3973 days old and we'd rather you create a new post instead of adding to this one. You can't reply in this post.

Recommended Posts

First Post!

Context: I crashed my 82' xj550 a couple of months ago. I hired a mechanic to fix it up. He did. I moved from Denver to SF, and was unable to get the bike started. I took it to a shop here. They said there are two big problems: 1) the mid-exhaust is leaking and needs to be replaced 2) the jetting needs to be adjusted.

Questions:

How do i tell where the mid-exhaust is leaking (diagnostically) and what replacement piece should i get?

Where should i look for it?

How do i adjust the jetting?

Any comments are appreciated!!

OrganicMuscle

Link to comment
Share on other sites

Do you want an ad-free experience? Join today and help support the Yamaha Owners Club.

To my knowledge you adjust the jets by purchasing a set of them and find out which works best. check your manual to find out what size the jets are as standard. Start with the biggest jet and work your way down. As far as the exhaust goes... no idea mate.

Link to comment
Share on other sites

At the risk of sounding stupid... would either of those be reason for it not starting or would they just cause it to run rough? :bag:

Link to comment
Share on other sites

@Sacha it runs rough, but i would like to get the exhaust fixed and the jetting adjusted before i start riding regularly.

@kkrub good call on the jetting. Definitley the easier of the two problems. I still have no idea on the exhaust ...

Link to comment
Share on other sites

re; mid-exhaust is leaking and needs to be replaced

well if the system is the same as the xj seca type it is in two parts, the front section and the muffler/silencer, between the two the pipes merge - this always seems to be the point that the rot begins and usually in the inaccessible crease thereabouts, when mine started blowing (you can feel the exhaust comming out) i bunged the area up with steel wool and wrapped fence wire round using pliers - it held ok until i got the whole thing replaced. hope that helps american friend :spin2:

Link to comment
Share on other sites

@Sacha it runs rough, but i would like to get the exhaust fixed and the jetting adjusted before i start riding regularly ...

My bad... I must've still been asleep. Thought it wouldn't start. :)

Link to comment
Share on other sites

Depends on which system you have really original ones have 4 headers 1 central block and 2 silencers 1 out each side or pattern ones have 4 headers 4 way multi connector and 1 silencer usually out the right hand side. So if you have the original one you only need to replace the central section if you have the pattern type then you have to replace the silencer with the 4 way adapter on the end. Best way I can describe it really otherwise look it up on the net. DON'T replace the whole thing unless you need to as it will cost a bloody fortune in the UK it's about £350 that's about $470. I could of course be completely wrong and yours is nothing like this but hope some of it helps. :jossun:

Link to comment
Share on other sites

First Post!

Context: I crashed my 82' xj550 a couple of months ago. I hired a mechanic to fix it up. He did. I moved from Denver to SF, and was unable to get the bike started. I took it to a shop here. They said there are two big problems: 1) the mid-exhaust is leaking and needs to be replaced 2) the jetting needs to be adjusted.

Questions:

How do i tell where the mid-exhaust is leaking (diagnostically) and what replacement piece should i get?

Where should i look for it?

How do i adjust the jetting?

Any comments are appreciated!!

OrganicMuscle

If you have a cracked or leaking collector box it will effect the carbs (CV) as the back pressure will be different but once this is fixed the carbs should work correctly again without any jetting.

Link to comment
Share on other sites

@slice - i think you've got the right idea. It has the original design with 4 headers and 2 silencers. I think i need to track down the middle section and get that replaced.

BUT, first i've got to get this thing started. I think i gave a little bit of bad information here. The mechanic was able to get it started. But, i just gave it a shot and i wouldn't start. It would turn over, but it wouldn't start. Any best practices that would be useful for getting this thing to start? Below it looks like the mechanic added starter fluid to get her going, but obviously that was a short term solution.

Here are the complete notes from the mechanic:

All cylinders mechanically test very good.

Spark plug caps appear old and cracked, will replace plugs and caps and retest. DONE
Unit starts ok when warm, otherwise needs starter fluid, idle is not steady.

There is a major exhaust leak at the mid-pipe/ collector, this can cause poor running Addl, bike may have been jetted to run in Colorado (where/altitude?)

With Pod filters, and exhaust leak/open pipes will be running lean Test rode and at higher rpms runs ok, has full power.
For best running, would likely need to look into jetting correctly, but not until exhaust parts can be replaced...

05/14/2013 Attempted to start bike when cold - will not start, even with full choke.

Link to comment
Share on other sites

Ok see where your coming from with that last bit of info, you will have problems getting it to go or run properly until you get the exhaust sorted but you could try a shot of EASY START or as you said starter fluid, make sure you have fresh fuel in it and turn the tap/petcock on and start the bike with the fluid stuff just keep doing it till the fuel runs through and that should get the thing running at least so you can hear it and annoy the neighbours!! the more you run it the better it will be and the easier it will be to start, sounds like you need to fiddle with the carbs as if it's been jetted and the needles have been changed for altitude then you will have to fix that as soon as possible, all that info should be in your manual as to what to set the carbs to for sea level running. best of luck with your project, let us know how your getting on. :jossun:

Link to comment
Share on other sites

Alright i've got an update for you guys.

Saturday morning i wandered into a couple of bike shops just to make double sure that your advice was the right advice. I'm new. The general concensus was clean the carbs, get her started, fix the exhaust leak then adjust the jets as needed. Cool.

I took out the carbs, and they looked pretty damn good. The jets, especially the pilot jets needed a good soak in the carb cleaner. Otherwise, all of the seals were really solid no cracks or gunk. The floaters looked good, although i didn't meaure the hieght. And the refill bowls were solid as well. I will say that when i removed the carbs A LOT of gas came out with it - at least 2 or 3 cups worth. I'm wondering if the carbs weren't flooded? I did notice that petcock valve was leaking a bit after i took the tank off. When i returned to the bike Sunday morning, there was a nice little puddle under the petcock. I wonder if this has something to do with the issue? Any ideas to test?

As of today the carbs are together and just need to be added back to the bike. Side note: total rookie mistake in not taking pictures of the carbs before dismantling them. I'll be searching for some pics to help guide me through the process later.

I'll update later this week or the weekend when i get the carbs back on and some fresh gas in the tank. My plan is to get the carbs on, start her up, identify the leak in the midline exhaust, temp fix, order part, permanent fix, adjust jetting with new exhuast piece(s).

-Sean

Link to comment
Share on other sites

Hi OM, vids look ok and should give you the info you need, glad that the shop agreed that it was probably just crud in the carbs and the exhaust that needed sorting, as you say just find the exhaust leak and bung it up temporarily for now that should make it much easier to sort out the running probs, I know in the vid the guy talked about carb cleaner and it's really important that you do not get it on the gaskets or seals as it will eat them away and then you will need a carb kit to repair your mistake, they are expensive for what they are so just be careful splashing this stuff around. If you have the manual for the bike just follow the instructions for setting the needles to sea level or normal running, as your going to have the carbs apart anyway it will just be remove the clip on top of the needle and move it up or down to the place it should be for your location, be careful when you take the clips off as they can jump off under tension and disappear without trace over the horizon, also be careful when putting the diaphragm back on that you don't trap it in the joint between the carb and the top, just do it up loose first and try the slide to make sure it runs smooth before you tighten it down. That's enough for now hope you get it sorted and get to ride before the summer ends. :jossun:

Link to comment
Share on other sites

×
×
  • Create New...