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XS650 BigFin KIt
- Thread starter ihaxs650
- Start date
Bob Kelly III
Ranch Kid from way back,.... that got Old !
(Just so Skull won't have a Hissy-fit....)
as you were the first to mention it being out of time with the cam....
....
thanks Tomterrific !
.....
Bob......
ihaxs650
XS650 Enthusiast
Thank you all for the support. There has been several suggestions from different members that i should check the cam timing. So here goes!
This is the bike at TDC.
Here is the cam timing at 180. I marked where the small hole is with yellow chalk because it is very hard to see.
I believe this confirms that the cam chain is installed correctly. More updates to follow.
This is the bike at TDC.
Here is the cam timing at 180. I marked where the small hole is with yellow chalk because it is very hard to see.
I believe this confirms that the cam chain is installed correctly. More updates to follow.
Mr. Kelly, sir, with all due respect and more, to accurately inspect cam timing there is no need whatever to remove the head cover.In fact the head cover must be in place to accurately inspect cam timing. The job is done thus. Set valve adjusters to the cam maker's inspection lash, mount a degree wheel on the crank, and set up a dial indicator on a valve spring retainer with the shaft of the indicator running parallel to the valve stem. With the degree wheel zeroed at TDC, valve opening and closing events can now be read by observing the action of the valves with the dial indicator and reading where those events occur in the rotation of the crank on the degree wheel. Compare same to maker's specs.
....
....ahem........
I'm not a mechanic, never pretended to be one......just to clarify my position.........
In stead of creating a blow back from you Bob, i posted my cough in the hope you would realize the advice you gave, needed to be revisited and maybe revised for clarity's sake.
OP has stated the bike starts and idles fine and runs up to 3 grand then hits a wall...........
If the timing was off by one tooth on the cam sprocket i would be confident in stating the bike would be hard to start.......If/when it did start, the chances of it idling would be slim......and there would be backfiring and running very rough and the throttle would need to be constantly played with to stop it dying.........
As the pics in post 23 show the cam cover removal is all that is needed to check if the cam sprocket hasn't jumped the chain.
I thought you had gone through this process in the early stages of your bike and may have forgotten.............your the mechanic, so maybe i'm wrong.......hence the cough.
its all mute now...........OP knows a thing or two, so for me it is just as important to find out where the skill level is before giving definite advice
Bob Kelly III
Ranch Kid from way back,.... that got Old !
OK I submit ! I thought you had to see the notch on the side of the cam gear to make sure it was level.....
My Bad.... glad to see that it looks like it is in time anyway !....
My experience has taught me that if the cam is off one tooth to the advanced side it will be hard to start but one tooth to the retarded side it will be real easy to start...abnormally so... but I admit this is with cars and not bikes and there is a huge difference
Thank you Griz and Skull for pointing out my error....
and Skull you are a mechanic even though you say your not, anyone that has turned wrenches for more than 5 years straight qualifies.
I am a mechanic.... Not a great one by the standards here on this forum, but it takes all kinds to make the world go around ! I take pride in being able to get any engine to run.... or fix anything.... although in reality I can't.... but I give it a darn good try ! LOL
I never have said yet that my way is the only way to do something.... and never will
.....
Bob.........
My Bad.... glad to see that it looks like it is in time anyway !....
My experience has taught me that if the cam is off one tooth to the advanced side it will be hard to start but one tooth to the retarded side it will be real easy to start...abnormally so... but I admit this is with cars and not bikes and there is a huge difference
Thank you Griz and Skull for pointing out my error....
and Skull you are a mechanic even though you say your not, anyone that has turned wrenches for more than 5 years straight qualifies.
I am a mechanic.... Not a great one by the standards here on this forum, but it takes all kinds to make the world go around ! I take pride in being able to get any engine to run.... or fix anything.... although in reality I can't.... but I give it a darn good try ! LOL
I never have said yet that my way is the only way to do something.... and never will
.....
Bob.........
Bob Kelly III
Ranch Kid from way back,.... that got Old !
I am Still intrigued.... what could cause this engine to not want to Pull hard above 3k RPM ? if this is a 1980 to 1984 bike perhaps the TCI ignition is giving up or has decided not to work on the spark advance .... that would do it...
spark advance is necessary for power above 3k RPM weather it's a points machine or TCI .....
All things being equal I would say spark advance sense the cam seams to be times correctly.......
if it's a TCI unit then look up the fixes of the TCI unit in the tech section... I know there isn't much on fixing a TCI unit as I found myself following links to different sites hunting for fixes myself....
re soldering the connections in the board and replacing components that look like they have over heated is about all I got ( also replacing the 4 diodes) ....strangely enough that seams to cure most ills with the TCI unit... LOL
however if it's a points bike , I can't remember the year and I don't feel like re reading the entire thread right now, but if it's points it has a mechanical spark advance on it and that should be simple to fix ! sounds like it's not moving at all ! free it up , clean and lube it up and it should work ! .....
Hope you get it going good soon ! summer is almost over !
....Bob.......
spark advance is necessary for power above 3k RPM weather it's a points machine or TCI .....
All things being equal I would say spark advance sense the cam seams to be times correctly.......
if it's a TCI unit then look up the fixes of the TCI unit in the tech section... I know there isn't much on fixing a TCI unit as I found myself following links to different sites hunting for fixes myself....
re soldering the connections in the board and replacing components that look like they have over heated is about all I got ( also replacing the 4 diodes) ....strangely enough that seams to cure most ills with the TCI unit... LOL
however if it's a points bike , I can't remember the year and I don't feel like re reading the entire thread right now, but if it's points it has a mechanical spark advance on it and that should be simple to fix ! sounds like it's not moving at all ! free it up , clean and lube it up and it should work ! .....
Hope you get it going good soon ! summer is almost over !
....Bob.......
It's a temptation on forums like this to try to troubleshoot by tossing out every guess you can come up with. Unfortunately that sort of procedure doesn't work very well in the real world where tools meet tasks. Troubleshooting is a matter of elimination; you start with the combustion tripod (ignition, compression, fuel) and test for sources of grief.
OP, you've tested compression and you know that it's healthy. You've tested ignition timing and you know the ignition is timed correctly and advances as it should. You've inspected cam timing by observing the position of the pin holes in the camshaft, so you know timing of the OE camshaft is correct. You've found a charging system defect and corrected it.You found a crankcase breather defect and corrected it. So far, so good!
Now there's a little principle that we forget too often, which is that some electrical problems show up only under load.So the next thing you might check is every connector in the TCI system that the liars at your shop ("Didn't know there was a problem, didn't test it above 3K, your gearing is too high," etc.) may have pulled apart. While you're testing, with the key and kill switches on, compare battery voltage to voltage on the 12V line into your ignition. If there's more than a 0.5V difference, clean switches and connectors.
Did the shop monkey with your carburetors? Maybe not, maybe so. You might want to have a look at the slide diaphragms.
My bet is on ignition defect. Good luck to you.
OP, you've tested compression and you know that it's healthy. You've tested ignition timing and you know the ignition is timed correctly and advances as it should. You've inspected cam timing by observing the position of the pin holes in the camshaft, so you know timing of the OE camshaft is correct. You've found a charging system defect and corrected it.You found a crankcase breather defect and corrected it. So far, so good!
Now there's a little principle that we forget too often, which is that some electrical problems show up only under load.So the next thing you might check is every connector in the TCI system that the liars at your shop ("Didn't know there was a problem, didn't test it above 3K, your gearing is too high," etc.) may have pulled apart. While you're testing, with the key and kill switches on, compare battery voltage to voltage on the 12V line into your ignition. If there's more than a 0.5V difference, clean switches and connectors.
Did the shop monkey with your carburetors? Maybe not, maybe so. You might want to have a look at the slide diaphragms.
My bet is on ignition defect. Good luck to you.
When you checked ignition timing, I assume you used a timing light, At idle it should be between the legs of the U marks on the stator. When you rev it up does the rotor mark move over to the left?
On the points bikes they had a full advance mark on the stator. The TCI bikes did not. There is a notch on the bottom edge of the opening you look through to see the stator. The timing will move over toward that notch. I can't recall right off whether it's the right edge or left edge of that notch that marks full advance.
As you rev the engine the ignition should advance over to the notch at about 3000 rpms. If it doesn't then it could be the magnet in the rotor is weak, Easy to check for, unplug reg/rec and run engine, watch for advance. Easy fix too, just glue a new magnet on top of old magnet.
If it still won't advance, it maybe the pick ups on the stator. Black oblong item with three wires, you check ohms from the B/W wire to G/W and R/W. The 80 -81 pick ups should be 550-850 ohms, 82 on should be 630-770 ohms.
If your pick up tests ok then the TCI box may be faulty. It can happen anytime.
It maybe just a bad connection. Pull apart all wiring connectors for the TCI box and pick ups. Clean any corrosion you find, a thin coat of grease, the special dielectric grease is best but most any light grease will help prevent more corrosion.
The weak magnet was the issue on my 81, start and idle fine but wouldn't take throttle.
Leo
On the points bikes they had a full advance mark on the stator. The TCI bikes did not. There is a notch on the bottom edge of the opening you look through to see the stator. The timing will move over toward that notch. I can't recall right off whether it's the right edge or left edge of that notch that marks full advance.
As you rev the engine the ignition should advance over to the notch at about 3000 rpms. If it doesn't then it could be the magnet in the rotor is weak, Easy to check for, unplug reg/rec and run engine, watch for advance. Easy fix too, just glue a new magnet on top of old magnet.
If it still won't advance, it maybe the pick ups on the stator. Black oblong item with three wires, you check ohms from the B/W wire to G/W and R/W. The 80 -81 pick ups should be 550-850 ohms, 82 on should be 630-770 ohms.
If your pick up tests ok then the TCI box may be faulty. It can happen anytime.
It maybe just a bad connection. Pull apart all wiring connectors for the TCI box and pick ups. Clean any corrosion you find, a thin coat of grease, the special dielectric grease is best but most any light grease will help prevent more corrosion.
The weak magnet was the issue on my 81, start and idle fine but wouldn't take throttle.
Leo
ihaxs650
XS650 Enthusiast
Thanks to everybody for the information and suggestions as i am very perplexed with no revving under load.
Hit a snag with the Fleabay regulator/rectifier, the spade connector on the red wire is not fully inserted into the body. It slides in and out!
I ordered the replacement connector from Mikes and the crimping tool from Cycle Terminal.
Hit a snag with the Fleabay regulator/rectifier, the spade connector on the red wire is not fully inserted into the body. It slides in and out!
I ordered the replacement connector from Mikes and the crimping tool from Cycle Terminal.
There's a small tang on the connector that catches on a shoulder in the nylon body, prevents it from slipping out during connector insertion.
Connector removal tools slide into the body and press that tang down, so it can be removed. Not uncommon to find one that's not been rebent back up...
Connector removal tools slide into the body and press that tang down, so it can be removed. Not uncommon to find one that's not been rebent back up...
ihaxs650
XS650 Enthusiast
TooManyXS1Bs, Here are the pictures to the connector, somehow the tangs are missing!
Here is the other side....
I am going to replace this one connector and see how it goes!
Here is the other side....
I am going to replace this one connector and see how it goes!
ihaxs650
XS650 Enthusiast
Once i have my charging system fixed and if that does not resolve my revving issue under load then i am going to look closer at the TCI system.
grizld1: I am definitely going to check for voltage drops!
XSLeo: I am going to unplug reg/rec and watch the revving results.
grizld1: I am definitely going to check for voltage drops!
XSLeo: I am going to unplug reg/rec and watch the revving results.
ihaxs650
XS650 Enthusiast
Retired Gentleman, XSLeo: I am waiting for parts to resolve my no charging issue and decided to start the bike with the regulator/rectifier disconnected. On a fully charged AGM battery of 13.7 volts and the bike in neutral the beast winds out to 6000 rpm with a blip of the throttle. This is a test not under load and i am not sure what the results mean. Need to get charging system working!
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This means the small trigger magnet on your alternator rotor is very weak..................magnets weaken after 37 years.
I hate to say I told you so, but my post #7 from March 15 reads:
"Unplug the rec/reg combo unit, and then see how the engine revs up. The trigger magnet gets weak over the years, and thus gives a weak signal to the TCI. Unplugging the rec/reg removes the rotor magnetic field, and may allow the weak magnet to do its job. Simple easy test to try."
Do a Search for "rare earth magnet", for threads that have over come this problem.
I hate to say I told you so, but my post #7 from March 15 reads:
"Unplug the rec/reg combo unit, and then see how the engine revs up. The trigger magnet gets weak over the years, and thus gives a weak signal to the TCI. Unplugging the rec/reg removes the rotor magnetic field, and may allow the weak magnet to do its job. Simple easy test to try."
Do a Search for "rare earth magnet", for threads that have over come this problem.
ihaxs650
XS650 Enthusiast
Looks like i will be JB welding a rare earth magnet to my rotor!
You're on the right track now......................be sure to reply back on this thread, so we all know the progress.
mrriggs
XS650 Junkie
Which side of the engine are you looking at? The threaded end of the cam needs to be on the right side. It's possible to put the cam in backwards. You can line up the dots and it will run, but not well.
Also, it appears that you have double-lip seals. Notice that the outer lip is just barely on the corner of the cam. This is the cause of your oil leak. The original seals are single-lip and sit in further from the end of the cam.
ihaxs650
XS650 Enthusiast
Mrrigs: Pulled the right cam side cover and the camshaft has threads. Ordered the OEM Yamaha seals from boats.net i have them in my possession. I did not realize that the installed seals are non OEM.
mrriggs
XS650 Junkie
Sound like you got it all covered. 
