On the road again at 40.............the bike that is

[robinc]

Interesting 5twins, thank you. I guess the obvious is if the condenser is dead, no spark, providing everything else is good. To test, swap the leads as 2M suggested and the problem will follow.

When I can get back at it, out of interest I will try this, curious and sure easy to do.

Looks like you were right, new points will be going in.

It does raise another question to you and RG.
If they die do either of you have any experience with Mike's/XS650Directs condensers?

 

[MaxPete]

I have bought a set of XS650 Direct condensers and they work fine on Lucille....but YMMV.

Pete

 

[retiredgentleman]

No experience with Mikesxs/XS650direct capacitors. However, a basic capacitor is so simple to make, I think any manufacturer could make them successfully. They are just aluminum foil and wax paper, rolled up into a cylinder, with 2 wire leads soldered on.

 

[TwoManyXS1Bs]

Taking a step back. Just a rehash, the salient points:

...they are actually running no better and maybe a little worse than they were before I replaced the leaking throttle shaft seals.

At mid and upper throttle ranges, smooth, steady pull, no hesitation, but that's the easy part isn't it.

The idle is still erratic at stops, surging higher, turn down idle screw. ride a bit, idle surges again and hangs for a bit before dropping and wanting to stall, then turn up idle screw.

I pulled the plugs and they are carbon coated. Either it's running rich or maybe I have an ignition system problem?

Perhaps the carbs are good now and are allowing the problem that lies elsewhere to surface more readily...

My official "clutching at straws" list...
...just for kicks n grins? try a set of BP6ES ,1 grade hotter plug...

Leaking throttle shaft seals will cause a lean idle condition.

If, at some point in time, the pilots were upped to compensate, and now the seals are fixed, a rich idle condition could happen, leading to carbon-fouled plugs and rough idle.

Carbon-fouled plugs can cause rough running anyways.

What pilot jets in there?

 

[robinc]

Hey 2M,

What pilot jets in there?

Had a look when I had them apart. All stock jetting.
135 Mains, 27.5 pilots. Made sure they and all passages were clear. Mix screws set to factory 2 1/4 turns out, new mix screw o-rings, new needle jet o-rings.

I have pulled the plugs 2 or 3 times as I have been going through this latest rough running situation, then clean with carb cleaner, a tooth brush, and compressed air. Also installed new plugs, and they continue to be carbon fouled when I pull them again. When running yesterday noticed smoky exhaust, so maybe carbs are set too rich. Looked more black than white, but didn't run long. Haven't had any carb or petcock leaking problems but checked oil, no fuel smell.

I haven't done any fine tuning on the carbs yet as it's not idling smooth enough to get it to idle down for the dead cylinder method.
Once this issue is resolved, I will do that and I'll finally put that ATF manometer together to sync more accurately.

My next step as per gggGary's and 5twins suggestions is to install new points. Then I'll also know if it's bad points causing idle fluctuations and my advance to hang, or if the advance springs need attention.

I didn't have time for much yesterday other than to try your swap condenser leads test out of curiosity.
Still starts first kick every time however It's actually running worse than it was Monday. Swapping condenser leads made no difference.
If it is bad points, they are degrading daily.....lol.

My hope is on points at this point....lol.

Thanks again for everything.

 

[TwoManyXS1Bs]

Just a coupla quick/easy tests on the pilot circuit.

Try on each carb, while it's idling:
- Run the mix screw in fully. Should get a significant change.
- Return the mix screw setting.
- Place a finger over the pilot air port. Should get a significant change.

If no detectable changes, suspect the pilot circuit...

 

[robinc]

Ok cool, will do, thanks 2M.

 

[Mailman]

How's it going Robin? Have you had a chance to work on your bike lately.

 

[robinc]

Two posts ago, 2M gave me some tests to perform that would be quick and easy to try before changing points and messing with advance assembly.

Left side

• Turn in mix screw fully, stalls.
• Return mix screw, block Pilot air port, stalls
• Left carb pilot circuit looks good

Right side

• Turn in mix screw fully, should stall but runs really well, no miss, stumble or climbing idle….huh
• Return mix screw, block pilot air port, slightly rougher running, idle increases
• Right carb pilot circuit looks like it’s still plugged somewhere

So I figured 2M had me onto something here.

I must have missed something and wondered if pilot circuit must be blocked somewhere and the carb was compensating somehow and running off another circuit. So I tore them down again, which is no big deal, I think I’ve gone to the dark side as I actually enjoy working on carbs. Someday I hope to be able to get them to work again too.

Once again cleaned every orifice and passageway. I enjoy figuring out how they all connect and operate.

Found no blockages, but maybe something so fine carb cleaner or compressed air blew it out and I didn’t see it. But I figured it would have had to have been a full blockage to shut down pilot circuit.

Also installed new 135 Mains and 27.5 Pilots while I had them apart.

After remount:
Left side

• Turn in mix screw fully, stalls
• Return mix screw, block Pilot air port, stalls.
• Left carb pilot circuit looks good.

Right side

• Turn in mix screw fully, runs great, smooth, no miss, no hunting idle, will idle and purr right down to 700-800 rpm
• Return mix screw, runs rough again, block Pilot air port, idle increases
• Still looks like blocked pilot jet circuit but I can't see how.

So, I know that every carb port and passageway are clear.

How can pilot be affected this way? Fuel and air are coming from somewhere with the mix screw fully closed. Could the fuel be being drawn in from the left carb fed from fuel line link/crossover tube and the air from a leak?

At first the right side was backfiring a bit, had never had any real backfiring before. Then it got worse. Sprayed carb cleaner around exhaust pipe manifolds on both sides, no effect.

Then sprayed carb cleaner on the carb mounts, clamps are done up so both halves are tight together as per 5twins recommendation, no butterfly binding:

• Left side leaked on carb side of mount, idle increased slightly with CC.
• Right side leaks a lot worse on both carb and engine side of manifold, idle increase more dramatically with CC.

I thought I had tested all this, but that was awhile back.

Right manifold is badly cracked in several places the full depth of the carb mount area and rubber is very hard.
Left manifold has a couple small cracks, not very deep and is much softer. That makes sense as I remember replacing it years ago chasing a leak.

I had a couple of 78/79 manifolds that I got for $25 with one of the carb sets I bought. Hoping they’ll be good, and will be nice to have those barbs for syncing too.

They look OK. Didn’t notice any major cracking and they were softer.

Still waiting for the gaskets I ordered for them, so I picked up a sheet of Felpro gasket maker material from NAPA and made some gaskets. Installed with Hylomar Blue sealer on both sides, just to be sure.

As always, one easy kick, Idled smooth, turned idle down to about 700-800 rpm. (Don't know how accurate my tach is and haven't puzzled through how to use the tach feature on my 'Little yellow meter’ yet.) Then raised to 1200, and it ran just like it should, shut it off after a few minutes.

Was thinking I’d take it for a test spin, so put the air boxes back on and fired it up again.

Now that it had warmed up, all the rough running symptoms are back. Backfiring worse now, so where’s the air leak now?
The new right manifold is leaking on the carb side so badly I can hear chirping now. Didn’t need Bob’s hose-oscope, but used it anyways just because it’s cool,and it's definitely leaking around the carb/manifold joint.

Sprayed left and right sides with CC, gaskets are good, but right carb side of manifold is leaking, maybe slight effect on left. Clamps are tight together.

However, the pilot circuit on the right side is now operating properly and will stall with both tests. I guess that proves that this manifold is sealing somewhat better than the last one.

Since I have it I'm going to try swapping my old left side manifold for my new right and see if there is any improvement.

So looks like I may shopping for new carb manifolds. I know I don’t want to use Mikes/XS650Direct.

Any suggestions for Manifolds? Or for anything else I can try?

Will get to new points, but don’t see the point in that yet.

 

[MaxPete]

No suggestions Robin (I'm sure NOT a tuning expert) - but dang!

 

[Mailman]

Robin, intake leaks can sure make your bike act crazy. I have spent an inordinate amount of time chasing them down. My bike also went from a nice running bike to a coughing , popping , erratic beast seemingly overnight. The tough thing is , it seems like it's never just one thing , but rather a combination of small things.
Just this last time, it was a combination of mechanical issues with my carburetors, timing and carburetor adjustments. Once I got these issues sorted it was like some magic transformation. For me personally I just had to stop and be methodical and go step by step through basic checks, I took my carbs apart and reset everything to factory spec, I re checked my timing, I followed the basic carb balancing instructions in this post.

http://www.xs650.com/threads/simple-carb-mixture-screw-and-sync-adjustments.33791/

Eventually you will start narrowing down the problems. Keep the faith man. These old bikes have some entrenched gremlins , once you start ridding them and start to see daylight the rewards are worth it.
Bob

 

[weekendrider]

The manifolds are dedicated left/rights. It won't work well to use a left on the right. There are some on e-bay you want to search part #2F0-13586-00-00 (L) and 2F0-13596-00-00 (R). They are not cheap. You might search the forum for posts on JBM manifolds. Mikes products are not the answer to your ills.

 

[robinc]

No suggestions Robin (I'm sure NOT a tuning expert) - but dang!

Ya Pete, she's still fighting back, but we'll get her sorted out.

I followed the basic carb balancing instructions in this post.

Thanks for that link Bob. Hadn't seen that one and lot's of good info. Once I get these manifold leaks sorted I'll try that instead of the dead cylinder method. Good info on syncing as well. Take care.

 

[robinc]

The manifolds are dedicated left/rights.

Doh, yes that's right WER. I guess that's why they have a little L & R on them.....lol.
I guess in my frustration I was looking for another test. Need to just clear the head.

I know Mikes ain't the answer.

Will do some searching, thanks for the info.

 

[TwoManyXS1Bs]

Excellent, Robinc!

You've got a good grip on the issue.


The student is becoming the teacher!

Something else to diddle with:
Have a close look at your carbs' spigots.
Check for roughness and casting flash.

Fine rattails, sandpaper, whatever. Smooth those surfaces.
Use a thin smear of silicone grease on those, and inside the rubbers.
Helps 'em to slide in there, and helps with sealing...

 

[robinc]

Thank you TwoMany-san. And thanks for the latest tips, will have a look at that. I might have some extra carbs around here somewhere I can check as well.
Will try some silicone now and use it in the future.

I can see how after 40+/- years of heat and fuel these rubber manifolds will deteriorate and I wonder how many others have rough idle, erratic idle, major/slight backfiring problems as a result?

Once again, Many thanks!

 

[MaxPete]

Indeed - a likely cause, I'd guess.

 

[robinc]

So I thought I would spend a little more time delving into this deteriorating manifold issue. I always looked at them but never dug deep enough to see how bad they really might be. Really needed 2 or 3 pairs of hands to get these pictures so I just used some small scrap doweling.

This is the right side which is the real problem side. This thing isn't about to seal anything other than it's own fate.

Those cracks go the full depth of the the carb spigot mounting section. No wonder they were leaking so badly. This is an original (AFAIK), 40 year old manifold on a 77D.


The left side which performed much better doesn't look bad on the surface. This one is newer, purchased at a Yamaha dealer in 2005. I can't find the receipt right now but remember seeing it awhile ago and I think I paid about $75 for it then. According to my old shop log it was installed 04/16/2005. Bike was ridden until 2008 and then parked until last year.

As you pry the walls open the cracking is obvious.

Now these cracks only go so far as the 'vee' bead that the carb spigots lock into. But they were leaking slightly and will only get worse.

As mentioned above after 40 +/- years we can expect some deterioration but I wouldn't have though it would be as bad as that right side, and surprised that is so bad on a 4 year running manifold as seen on the left side. Maybe sitting is as hard on that rubber as running.

I still have 2 more manifold sets installed on bikes and will edit and update this post and this thread as I pull them off and inspect them.

'Remove and inspect carb manifold condition' is certainly now an item on my checklist.

 

[Mailman]

Holy cow Robin! Those manifolds are toast! Haha! Your new manifolds should really make a difference. As someone else mentioned, when you go to install your carbs into your new manifolds, smearing some di electric grease on the inside of the manifolds will not only help it seal, but will greatly ease the installation.
You're gaining on it. This will be a big step forward in ridding your bike of its air leaks.
Keep up the good work.
Bob

 

[gggGary]

Yeah that's kinda weird Rob, maybe something in the Canadian air? I seldom find a manifold bad enough to replace here in the great white North I'd expect southwestern manifolds to just crumble. My 99 royal star that sat in an Arizona carport has manifolds that look like dried mud but they still aren't leaking, yet...