Anyone done the valve timing on a twin cam?

beaver

beaver

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Ok, I know how to lock the crank at TDC.. and have checked both sets of cams for being in the right place... One side is, but the other side is a very small amount out. Sure it's in spec but being anal and wanting to get it all 100o/o right for my ownership I want to reset it. But reading the book does not tell you or show you how it works... Are you just undoing the sprocket bolt and it moves,,,, or is it on a tapper... Or some other way... I'll have a play at some time and once in I'm sure it will become clear. But if anyone has any tips/ explanations... It would be good to know before I get the spanners out.... Thanks for any info
 
the cam sprockets are on a peg/keyway they are not movable unless this altered.
 
I think may be it did, because there is a setting device to square up the two cams to each other and a TDC lock when setting... but must say, I thought id see something like a vernier sprocket or something... but no... just looks like it bolts straight on... so could be just a peg / key?.... as you say, thats your lot if it is??...
 
No, TDC is easy... And the link is about setting shims? We are talking here about valve timing and if the sprocket to cam interface offers adjustment each side...
 
beaver said:
No, TDC is easy... And the link is about setting shims? We are talking here about valve timing and if the sprocket to cam interface offers adjustment each side...
Click to expand...
Ah. Apologies! You're right on all counts.

Now I'm wondering why you would want to adjust the timing? Would bmw not have gotten it at its optimum setting already? Or do I have too much faith in them?
 
beaver said:
No, TDC is easy... And the link is about setting shims? We are talking here about valve timing and if the sprocket to cam interface offers adjustment each side...
Click to expand...

Looking at the camshaft on the real OEM parts finder it looks like it's just bolted on, have a look and see. As an aside could I say that i had a recall done by the dealer to change the reluctor ring that fits on the same bolt that holds the camshaft sprocket on( you'll see it in the same picture) and it turned into a fiasco. First they could not get the bolt off, they had used an impact driver, the timing had jumped,and they damaged the camshaft. The bike was with them for weeks and never ran right when I got it back, my hands were numb with the vibes after a few miles. I took it back to the dealer a few times and they said it was within spec. I took it to another dealer and their mechanic told me the timing was one or two teeth out just just as I drove it into the workshop. Anyway ( rant finished ) the bolt may be on with some super strong locking compound, and your timing could be slightly out.
 
Mac One said:
Looking at the camshaft on the real OEM parts finder it looks like it's just bolted on, have a look and see. As an aside could I say that i had a recall done by the dealer to change the reluctor ring that fits on the same bolt that holds the camshaft sprocket on( you'll see it in the same picture) and it turned into a fiasco. First they could not get the bolt off, they had used an impact driver, the timing had jumped,and they damaged the camshaft. The bike was with them for weeks and never ran right when I got it back, my hands were numb with the vibes after a few miles. I took it back to the dealer a few times and they said it was within spec. I took it to another dealer and their mechanic told me the timing was one or two teeth out just just as I drove it into the workshop. Anyway ( rant finished ) the bolt may be on with some super strong locking compound, and your timing could be slightly out.
Click to expand...

One or two teeth!... I'm talking 1/2 a deg here... would you not be contacting valves to piston at that amount out? No wonder it never ran right!.. also an impact gun... you'd be pulling on the cam chain to hold it (unless they held it some other way)... thats very poor... and this is why I tend to DIY .... A mate of mine once had a V8 come back not running right.. well under power and making a horrid noise... They had left a plug out at the back FFS!... and this was a top BMW garage!... how does it happen...
Anyway, thanks, yes, will have a look as you say in the parts finder :thumb2

Slippery... yes, I'm sure they will be fine if its running right. TBH I'm just playing here... but for cam to cam timing and timing to the crank, they may (as it appears they do) enable you to adjust the cams to get them right... As the cam chain / Guiders wear a bit, the end result is the Cam timing goes out... so this allowys you to re-position back to where BMW intended...
TBH +/- 2 deg should make little differance
 
This lack of valve timing adjustment bugs me too. I've found that boxer twins and v twins rarely have perfect timing. I'm not talking about them being "wrong" as such, but not perfect.
I guess you need to buy (or modify) slotted camera wheels or similar.

Sent from my GT-I9505 using Tapatalk
 
stanley said:
This lack of valve timing adjustment bugs me too. I've found that boxer twins and v twins rarely have perfect timing. I'm not talking about them being "wrong" as such, but not perfect.
I guess you need to buy (or modify) slotted cam wheels or similar.

Sent from my GT-I9505 using Tapatalk
Click to expand...



Sent from my GT-I9505 using Tapatalk
 
stanley said:
This lack of valve timing adjustment bugs me too. I've found that boxer twins and v twins rarely have perfect timing. I'm not talking about them being "wrong" as such, but not perfect.
I guess you need to buy (or modify) slotted camera wheels or similar.

Sent from my GT-I9505 using Tapatalk
Click to expand...

Mmmm.. so is it fixed?
 
indeed.... maybe they are fixed... only 1 way to find out, but its a bit cold in the garage right now.... had enough for 1 weekend :)
 
beaver said:
indeed.... maybe they are fixed... only 1 way to find out, but its a bit cold in the garage right now.... had enough for 1 weekend :)
Click to expand...

I think most Japanese bikes have fixed cam timing (no adjustment for timing accuracy). Some will need new cams when the sprockets wear. Timing will gradually lag as the cam chain stretches but that will be down to service intervals. Cam chains don’t last for ever.

There was a timing retard(?) kit for 1150s to boost mid range power. Don’t know if such a thing exists for 1200.
 
its just the length of the chains on these things... so stretch is more of a problem... also the Jap bikes are multi link where as these are single... ?
 
Honda used the toothed multilink chain on their 80s bikes. Longevity was not an issue they were guaranteed to fail.
Roller chains running in oil will last really well and a longer chain shares the valve lifting loads over more links. The chain will move forward so on each crank turn a different group of links take the strain.
Service life of cam chains? What does BMW say?


Sent from my iPhone using Tapatalk Pro
 
Yes its an old thread - I understand that the camshaft sprockets are on a taper where they locate on the camshafts, allowing accurate adjustment once the cam-chain tensioner tool is fitted.
 
Nippy Normans supply Touratech, Wunderlich, Desert Fox and many other makes of accessories.
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