Cam/Crank chain timing riddle

PAUL! If I am ever on that side of the pond I will buy you a pint my friend. I put a washer on it, I need to get a copper washer rather than a steel one. And I was extra careful making sure the tensioner was just perfect, about 1mm out and it fired up and was back to its old normal smooth sounding self, took her out for five miles and she was her normal self. So it seems that little washer was causing the ruckus and the chain will need replacing soon because it is stretched.

Thanks Paul, 5twins, Twomany, Hein, Angus and Brian for all the help, I couldnt have done it without your guys help, seriously I cant get the grin on my face knowing that she is up and running again.

All that is left is some timing on the points and recheck the valve clearances once I take it around the block successfully but it seems like its out of the woods.
 
:thumbsup::thumbsup:And the weather is still fine?

Hein

P.S. 1 mm out is a bit too loose. Turn it in flush with the back of the tensioner, as long as the pin moves a few tenth of a mm.
(method XS expert Heiden Tuning in Holland)
 
hein weijers said:
: 1 mm out is a bit too loose. Turn it in flush with the back of the tensioner, as long as the pin moves a few tenth of a mm.
(method XS expert Heiden Tuning in Holland)
Click to expand...

Sorry, wrong thinking!!

When the pin is 1 mm out and still moves during idling, the chain is indeed a little too long. The right procedure is still: tighten until the pin still moves a few tenth of a mm.

Hein
 
Yep that 1mm is clearly showing you're in need of a new cam chain. Now you know what the initial issue was and you're now clear on the cam chain requirement, I,d pop the engine and put a new chain in, check the rings, replace any seals and pop in some nice new gaskets.

Then you have a well refreshed engine that should serve you well for a few years to come and you can ride with some degree of comfort.

After all, I think you're now quite the expert at pulling that engine ;)
 
Yep that 1mm is clearly showing you're in need of a new cam chain. Now you know what the initial issue was and you're now clear on the cam chain requirement, I,d pop the engine and put a new chain in, check the rings, replace any seals and pop in some nice new gaskets.

Then you have a well refreshed engine that should serve you well for a few years to come and you can ride with some degree of comfort.

After all, I think you're now quite the expert at pulling that engine ;)
 
So after the initial 5 mile run I decided to take it to work, which it made it about ten miles before it died on the highway. It started to bog down and then it eventually cut out. I couldnt get it to turn back on. :shrug:

Luckily my brother was only mins behind me in his truck, with the motorcycle carrier, ha ha.

When I got it home I found some oil on the fins under the left hand side spark plug and under the exhaust port. It would turn on but barely and would run awful! Sputtering and wouldnt rev up. My question is could this be because of the cam chain? Im going to check compression and crack into the carbs but I dont get how the oil is leaking from the head gasket area on the fins. I did notice that I had too much oil in it so I drained some out, could this cause pressure build up and blow a gasket? Also I just got some brass washers for the four outter acorn nuts on the head and will re-torque the head down.

Any other suggestions?
 
I need to buy a new set of plugs, my old ones didnt seem to look any different than before, they are a little dark but it never was a problem. Not wet or oily, just dark dark brown. I checked each cylindar, left was 138psi and right was 140psi, so I did loose about 10psi of compression from doing the cam chain guide replacement. I also upgraded to the brass washers and re-tourqued the head down.

When I turn it on, I feel both exhaust pipes and both get warm, the right hand side carb will push air back out and pop, it also pops out of the exhaust.

I am charging the battery back up as it was at 11.94v. I didnt change anything else during the cam chain procedure. I need to grab some carb dip and break them open to see if anything is clogged. In line fuel filters look clean.
 
Hi - re-torque your head, chances are thats the reason for the leaks, especially as its been off recently. compression tests rarely show that problem up.

Get the head sorted first before delving into the carbs - one step at a time :)
 
Hello again Paul, it may seem that you are on your way to earning a six pack of ales from me, haha.

I did Re-torque the head when I replaced the washers, only one at a time. For the inner 10mm bolts I loosened then re tightened, and I did that all in the torque head order. Still the same issue of running like crap. I did notice the left carb was shooting air back out and popping.

Should I pull the valve cover and torque it again? I never pulled the head off, should this be my next step, pull the head replace gasket, put new yahamabond on the valve cover and re-torque both to specs? I havent touched the carbs yet.

I charged up my battery last night, I will see what the reading is tonight after work, it would have sit for about 20 hours.
 
Hi,

When you did the valve guides you'll have had the head off, so I assume you used a new base gasket and head gasket?

If you did - you can leave the engine in and re-torque the main bolts. If you didnt - pull the head and barrels, replacing the base and head gasket. The head gasket in particularly will need replacing as it compresses as its torqued down. Once its compressed, it really shouldnt be re-used.

Personally i torque the 8 large head nuts to 30 ft/lbs and torque the smaller bolts to manual spec.
 
I never replaced the valve guides, I just did the front cam guide, I never went below the head, only removed the valve cover.

I am curious as to why after 10 miles of fine riding it would all of a sudden act up in a serious manner? Thats why I assumed it was something else like carbs, plugs or electrical.

I didnt want to go as far as removing the jugs because I have to do all this outside and space is limited, and I dont have a work bench. The roomates where mad enough when I brought the motor inside for the cam guide:laugh:.

Why is it that if I do have a blown head gasket why it wouldnt show up in the compression test?
 
The headgasket is not blown, only the headbolts are too loose. And when you lose a few drops of oil, that does'nt mean that the compression is effected.

When you torque the head, it should best be done in minimal 3 rounds with increasing torque.
The headgasket is compressed during the process and when you have finished with the last bolt, the first is loose again. So keep repeating the process untill all the bolts are equal tight!:thumbsup:

How is the camchain timing now? Is it still o.k.?

Hein
 
Sorry, my mistake I meant cam guides not valve!

As Hein says, it's not blown just in need of tightening back up. Compression tests rarely reveal these issues.

So, we know that the head gasket hadn't been replaced. The only risk is that it's compressed to its max and despite torquing it down , it may not seal 100%. The only way to find out is run it and see how it fairs. Worse case scenario is you need a new head gasket
 

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