Dear All

I am trying to solve the problem on the engine noise. One of them looks like from inlet an outlet camshaft pinion. At certain position (not always get slack) either at inlet and outlet camshaft get slack and I can move them by my hand and I could identify that the noise is come from them. I am suspected that the problem is crankshaft timing pinion or fly wheel shaft. Are my suspects correct? And which one is the main problem crankshaft timing pinion or fly wheel shaft.

Please advise.

Regards
Rofiq

email (option): rofiqmgl@yahoo.com

Rofiq,

Sounds like your flywheels are out of line, you will have to remove the pinion and clock the shaft with a dial gauge. Bit hard with the keyway but you should be able to clock most of it.

Tim W

email (option): t.j.walker@btinternet.com

Hi Tim

Thanks for your help. Once I know that shaft if not align, do I need to change the shaft or just re-align? It will be big job then...

Regards
Rofiq

email (option): rofiqmgl@yahoo.com

Hi Rofiq...You don't need to replace the shafts (unless they are badly worn or damaged)...but you will need to remove the crank from the engine and retrue it if you find it is running outside of the laid down tolerances...

The shafts should run true to .002" or less....Ian

Hi Ian

Let me understand clearly about "retrue". Is it rotate the shaft and check with dial as Tim mentioned..? I am also little bit confuse regarding .002" tolerance. I saw at the standard document mention that .002" is related to "Thickness of engine shaft flange (both sides): High 0.253" Low 0.248". Is it the same as your reference for .002" number..? What does it mean "shaft flange" ? Sorry to much questions.

Regards
Rofiq

email (option): rofiqmgl@yahoo.com

Rofiq If the flywheels are bolted together by the big end and the wheels are not running true then the two shafts will wobble. There is lots to read on the technical page. Here Dave Plumb explains about building and truing your crankshaft. But is probably best left to an engine build shop who have the correct equipment.

http://www.wdbsa.nl/crankshaft%20rebuild.htm


Ron

email (option): ronpier@talk21.com

Hi Ron
Thanks a lot for your inputs. I have read Dave Plump explanation but need more deep understand. I am stay on Indonesia so far I don't know yet the good old engine build shop. Let me try either do by my self or go to bilder shop.

Thanks and regards
Rofiq.

email (option): rofiqmgl@yahoo.com

But before you remove your engine to strip it. Remove the cams and crankshaft pinion that drives them. With the bike steady with a jack or strong box under the sump so that bike can't move. Use a dial clock to check if the shaft is actually running out of true. As Ian said, a fluctuation of up to 0.002" (Two thousands of an inch) is acceptable. Probably easier if you get someone else to gently turn the engine over with a socket on the drive side nut while you set and watch the clock. Ron

email (option): ronpier@talk21.com

Hi Ron

Thanks for your advise and let me prepare. It will take time due to doing it during out of office work. I will update once I finish to check first at the bike. Regards Rofiq

email (option): rofiqmgl@yahoo.com

Hi

If you can take some photos Mr Defazio would be very interested in them. The photos need to be high resolution. See this post.
http://pub37.bravenet.com/forum/static/show.php?usernum=3155626639&frmid=16&msgid=1289576&cmd=show

I'm in Singapore, where in Indonesia are you?

Richard

email (option): dickie.bobbie@hotmail.co.uk

Hi Ricard

I have taken the photos and I will send them to Mr Defazio let him give me a feedback regarding my photos whether they are accepatable or not.

I am on Cilegon it is a bout 115 kM from Jakarta west side. Singapore and Jakarta is cery close if you have a plan to go to Jakarta just inform to me.

Regards
Rofiq

email (option): Rofiqmgl@yahoo.com

Hi Ron

I have dialed the main shaft and the gap is 0.225 mm.

I was trying to attache/paste the picture here but I could not. Any idea how to do it.

Regards
Rofiq

email (option): rofiqmgl@yahoo.com

You have to download your pictures from a photobucket account and copy and paste the html code. Took me ages to work it out!

If you have managed to measure it accurately, I make it nearly .009" which is over four times the prescribed amount. I don't know if that would cause the clatter though? I assume the noise can only come from the uneven meshing of the pinion and the cams. The cams can't wobble with the pinion as they're steady on their own shafts. Best wait for comments from others.

Ron

email (option): ronpier@talk21.com

Hi Ron

Here is the picture how did I measure the wobble :

http://s1035.photobucket.com/user/rofiqmgl/media/DSC_0281_zps0786a082.jpg.html#/user/rofiqmgl/media/DSC_0281_zps0786a082.jpg.html?&_suid=138614081722108296782720014044

At the certain position of main pinion and inlet valve cam pinion gets slack. The same condition happend also between main pinion and outlet valve cam pinion. Those are my though of clatter. If I shake one of the cam either inlet or outlet valve the noise is coming. Sorry My english is good enough to make it clear understanding.

Regards
Rofiq

email (option): rofiqmgl@yahoo.com

Here is your picture Rofiq.
I think others will agree that you should get your flywheels trued properly before anything else. It will make a good chance to check your big end and main bearings. Ron
PS. In fact looking at your gauge. It reads .255mm which is just over .010".

email (option): ronpier@talk21.com

You could also first take off the barrel and check the flywheels for true running, if they are OK there is also a possibility that only the outer end of the shaft is bend.

This outer end of the shaft is very small so probably easily bend. Don't know if you can correct that with the crank still in the cases....never tried.

I would also put the small pinion gear back on and check again as that is the actual running situation.

Just my thoughts, but I agree with Ron that checking the whole crank is the best option.

Good luck, Michiel / NL

Rofiq,
Ron is correct .010" is way too much, this is your problem. As the gear mesh goes slack it makes a noise, then as is it gets tight the gear teeth are hard together and this makes a wineing noise. The next job is to strip the engine and look at the flywheels. If you cannot get them trued at an engine shop you can try what i do with the M and B type engines.
First make sure the big end nuts are tight, then as the drive side crankcase has 2 bearings in it you can lay the cases on its side and drop the crankshaft into this case. As long as your main bearings are good you can clock the timing side flywheel. Take the crankshaft out before you tap it. Use a good copper hammer to do this. You need to tap the flywheel without the crankpin keyway in it. I cannot think which side this is but i think the keyway is in the drive side flywheel. So tap the timing side.
This does not sound easy but it is and has worked for me on all my M engines, I can get them to .002" to 003" after you have completed try your test again after the cases have been put back together. A good engine shop will have a set of flywheel jigs to do this correctly, but engine shops are not as common as they used to be.
Your worst scenario will be if the flywheels need wedging, this is when you measure the gap between the flywheels at the big end and then at 180 degrees then at 90 degrees each way. I don't think this is your problem but if it is the flywheels need striping and checking for bruising on the tapers on the crankpin. But again i don't think this will be your problem.
Sounds complicated but it is not. It's just a matter of understanding why and what you are doing.

Good luck
Tim Walker

email (option): t.j.walker@btinternet.com

Your results prove there is no question the fault is crankshaft misalignment (run out)...

There is no alternative to stripping the engine completely to sort out this problem...As well as making the timing gear noisy it will make the engine vibrate more, causes excessive loading of the main bearings and can damage the oil pump drive...

.009"-.010" is way over acceptable limits...I have tried to run cranks that are just a thou or to over the specified .002" limit and they are still noisy etc... ....As long as the tapers are not worn out in the flywheels where the crankpin fits in you should be able to retrue them OK..Badly worn tapers mean, effectively, the flywheels are unuseable... .Ian