Mechanical hypercondria and Engine clatter

[ambrose78]

Hi again,

I've been getting spooked lately. My bike is mking quite a racket of late and it has sparked mechanical hypocondria..  

Just wondering how much banging noise is normal for an R65?

a bit of history
About 6 months ago I though my bike needed a new timing chain. So ordered all the parts and got stuck in only to discover an almost new one had been installed by a PO some point in time. No visible wear and the plastic chain tensioner looking as good as new. So I put it back together as it was, reset the valves and continued riding...

Lately however it has been clattering alot and had a mild case of pops and crackles on deceleration so I've been getting worried that my bike may be suffering valve recession, especially given the recent threads running. It still pulls fine and idles smoothly if loudly.

Tonight I went about checking the valves  having travelled 4000km (or about 2500 miles) since the last check. I set them last time to 0.1mm (4 thou) for the inlet and 0.2mm (8 thou) for the exhaust.

current readouts as of tonight

right
exhaust 0.29mm (about 12 thou)
inlet 0.10

left
exhaust 0.25mm (about 10 thou)
inlet 0.10


which means the inlets are going fine with no perceptible change. The exhaust vale gap is getting bigger however. So doesn't look to be suffering the valve recession (phew) . What could be causing the exhaust gap to be getting bigger? usual wear and tear?
 
Do you think I have to worry about the clatter? or should I just tighten up the exhaust clearances a bit (perhaps 6 thou) and keep on riding?

Cheers


mope.. I meant for this to be posted in the Q&A section. Appologies

[Justin B.]

[movedhere] R65 Technical FAQ/Procedures [move by] Justin B..

[Semper Gumby]

OK - lots of stuff going on here.  Poping on deacceleration.  You have the idle mixture set too lean.  Open the idle mixture slightly (1/8 turn) and try it again.  If you have the Colortune plug set the idle mixture on the rich end of the blue range on each cylinder.  The colortune plug alows you to see the flame inside the cylinder!!!

As for valve clearences opening up...have you torqued the heads.  I would do this once and then not do it again.  Repeated torquing of the heads will result in a pulled engine stud (usually the upper aft one where the oil comes out of the case on its way to the cylinder head.)

Other noises: Sometime the valves are still noisy even when properly set to .004 in and .008 exhaust.  The trick is to make sure the end float on the valve lifter is about .002".  This requires three arms as you will need to retorque the four bolts holding the valve lifter while squeezing gently the two posts on the end of the valve lifter to tighten up the end float.  A really big set of plyers is required for this.

When you put in the timing chain parts did you have the fixed block on the left defleting the timing chain 1mm?  This seems to be secret information.

Other sources of clatter can be the solid lifters between the camshaft and the pushrods getting worn/beaten.

Another source is a thonking sound when the small end bearings get worn and out of round on the connecting rod.  This is usually apparent at idle but goes away above idle.

Then there is piston slap (which I have never heard) which doesn't go away above idle. (I think).

And of course there is timing and carb balance.  You do have those set properly right?

One last thing:  pull off the cylindercover.  There should be oil -- not a lot but everything should be wet.  If it is dry then a DPO might have re-assembled the cylinder with sealer on the base gasket (bad) and sealed off the oil pathway from the case to the cylinder head around the upper studs.

Good luck and let us know how it goes.  Some one else will now chime in with more intelligent answers...

One other possible solution is to get an iPod Nano and a set Etymotic ER-6i earbuds and turn the music up...  

[ambrose78]

Thanks for moving the thread Justin

One other possible solution is to get an iPod Nano and a set Etymotic ER-6i earbuds and turn the music up...  

Wow - noises gone!! definately the best solution so far..  

 If you have the Colortune plug set the idle mixture on the rich end of the blue range on each cylinder.  The colortune plug alows you to see the flame inside the cylinder!!!

Might have to get me one of these bad boys.

As for valve clearences opening up...have you torqued the heads.  I would do this once and then not do it again.  Repeated torquing of the heads will result in a pulled engine stud (usually the upper aft one where the oil comes out of the case on its way to the cylinder head.)

I have never retorqued the heads - sounds like a good thing to do - now to forage for the pesky torque wrench

Other noises: Sometime the valves are still noisy even when properly set to .004 in and .008 exhaust.  The trick is to make sure the end float on the valve lifter is about .002".  This requires three arms as you will need to retorque the four bolts holding the valve lifter while squeezing gently the two posts on the end of the valve lifter to tighten up the end float.  A really big set of plyers is required for this.

I have never done this so will need to look into this. How often is this required? - every check up or every one in a million kms

When you put in the timing chain parts did you have the fixed block on the left defleting the timing chain 1mm?  This seems to be secret information.

I did not know this part - if the other things haven't worked I'll look into this sometime over the Christmas break.

Other sources of clatter can be the solid lifters between the camshaft and the pushrods getting worn/beaten.

Another source is a thonking sound when the small end bearings get worn and out of round on the connecting rod.  This is usually apparent at idle but goes away above idle.

I hope it isn't these items.

Then there is piston slap (which I have never heard) which doesn't go away above idle. (I think).

I don't think I have that in the R65. I had that in a previous Valiant that I owned and this doesn't sound like piston slap. this sounds more clattery than than anything else.

And of course there is timing and carb balance.  You do have those set properly right?

Timing seems good without too much variation.  Carb balance - never 100% sure as it seems to get affected by changes in the weather - about to re do it this week after fitting some new accelerator cables currently on their way at the moment.

 One last thing:  pull off the cylindercover.  There should be oil -- not a lot but everything should be wet.  If it is dry then a DPO might have re-assembled the cylinder with sealer on the base gasket (bad) and sealed off the oil pathway from the case to the cylinder head around the upper studs.

There appears to be a reasonable amount of oil under the rocker covers, enough to always have the drip tray under when pulling them off

Thanks semper for the long and detailed post.