RE: cylinder studs: torque or length?

["Clive Liddell" <cliddell@xxxxxxxxxx>]

Hi John, and Welcome to Oilheads!

Unfortunately, it's early Sunday morning here in SA, and I have to depart for the Sunday bike run BUT I thought it important enough to say that you seem to be doing the torqueing completely WRONGLY!

I'm sure by the time I return many will have chimed in with the correct procedure - if not, I will do so myself.

Just to say that proper re-torquing has stopped the odd little cylinder head weeps that my bikes have ever had...

BTW Nice bike!  The R1100RS are very scarce here in SA and always treasured by their owners.  BMW only brought in a limited number, plenty of GS's and RT's and quite a few R's around though.

Regards
Clive Liddell
Pietermaritzburg, South Africa
'96 R850R ~81k.km
'01 R1100RT ~65k.km

> 
> I'm new here (apologies, in case I fracture some etiquette). I have a 1999
> R1100RS with 29,000 miles. I'm the original owner.
> b"	I had a slow oil weep around the right side head gasket 
> (dripping on the
> toe of the right boot)
> b"	I tightened the head nuts two times in 6,000 miles but this 
> did not stop
> the oil weep.
> b"	I decided to replace the head gasket and check the cylinder 
> studs for
> tightness.
> b"	Upon removing the heads, The studs all seemed very loose to 
> me b almost
> finger tight. This is the first time the heads have been off. (The dealer
> did the original retorque of the heads at 600 miles).
> b"	I couldnbt find a torque setting for the studs in the BMW 
> nor the Haynes
> manual. Just for the head nuts. If I tighten the studs to say 20Nm b they
> are too short. The Haines manual says they should have 152.5mm of 
> extension
> above the cylinder sleeve, except for the short one which is 
> 132mm. At 20Nm
> the longer studs are just 146mm, not 152.5mm.
> b"	I took them all out and reinserted them to the correct 
> lengths, but again,
> they seem really loose (barely register on a torque wrench)
> b"	So, I have doped them up good with a high-temp thread lock 
> and have put
> then in to correct lengths. But I wonder...
> 
> What is your advice? 
> b"	Do I go for the correct length no matter if they seem loose 
> (less than
> 5Nm)?
> b"	Do I tighten to say, 20Nm even if that makes them short 
> (say 146mm instead
> 152mm)
> b"	Or do I helicoil the whole bunch?
> 
> Anyone out there encounter this issue? Advice?
> 
> John Merlin Williams
> Ann Arbor, MI
> 
> --
> View this message in context: 
http://www.nabble.com/cylinder-studs%3A-torque-or-length--t1380784.html#a3707945
Sent from the BMW Oilheads forum at Nabble.com.

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