Dumb question: studs, oil filter plate for the holding of ..

Ventodue

Hero member
Location
France
This is for a RGS, btw.

You know those 3x 6mm studs that hold the oil filter plate?  Well, my question is: Is there any good reason not to replace them with a allen screws?

I ask, 'cos this is now the second time that I've had the thread strip on a stud; and frankly it's just a fiddle and a fart getting them out and replacing them.  For it just to happen again ...

So an alternative would be to simply use screws instead.  But then I wonder, why did Laverda chose to use studs in the first place ?

Any thoughts appreciated.

Ciao

Craig
 
Hi Craig,

I don't know the definitive answer, but IMHO the studs make it easier to mount the filter housing - as you know, the layout of the studs only allow you to fit the housing in one position - with screws it would be more fiddly, especially being positioned on the underside of the crankcases.
I'm surprised that you've had threads strip - too heavy-handed with the spanners?? I don't have the torque settings to hand, but if the O-ring's good, I can't imagine that the nuts need to be hauled up too tight.

However, I see no reason why screws won't do the job.

HTH,
Alan :)
 
the casing is a soft material. During the proposed live-time of the engine (150.000Km it was designed for), you will have to make roughly 60 Oil changes (every 2.500Km). If you ruin a thread of the studds, you replace it maybe and you are good. If you tighten the screw to much, you kill the threads in the engine casing. Not good.

I would stay with studs if possible anywhere on the bike, as it moves the problem to a part you can exchange and fix cheaply and as often as needed. You can fix a damaged thread in a casing only once or maybe twice...
 
At least from my point of view studs are a better idea:

1). A stud can be wound down and bottomed out in a blind hole to give maximum strength.
2). When bolts/allen screws bottom out in a blind hole while trying to tighten a cover they tend to strip the casing thread out.
2). There is a good chance of doing similar damage to the engine casing if you overtighten a bolt, however if a stud strips then it can be replaced easily with no damage done.

I am wondering what sort of studding you are using? It should last donkeys years.
 
Craig,

Perhaps you should use a shorter spanner. :D

Simon and Lothar are spot-on with their theories on why studs are used, normal engineering practice in the use of alloys.

I have fitted countersunk allen screws years ago on the 3C because of clearance issues to the works headers.  Haven't had a problem yet, but then I don't remove the strainer very often because there's a proper filter in my system.  Wasn't a speck in it 2 years ago, first time it was removed after about 40000km.

Also find it difficult to believe you're constantly stripping the studs!  Are you using 1/2" drive sockets?  These are far too heavy and too big to be of any real use on most motorcycle fasteners, only good for things like wheel axles, etc.  3/8" or 1/4" drive tools are usually more than ample for motorcycle work.

piet
 
Thanks guys.

1.  The explanation for why studs are used is what I thought, and it's nice to have a confirmation. Ta.

2.  Your contributions have got me thinking and I think I may an explanation for where I'm going wrong.  I use stainless nuts on these studs and I wonder whether they are galling, even tho' I use copper slip.  The threads strip when I undo the nuts, you see.
Does this seem likely?

P.s. No, I don't whack the nuts up tight  :o.  There'd be no point since the nuts aren't 'Doing a Job of Work'.  (?" drive socket, Piet?  You jest! :D  Haven't used one of those for years. Ok, maybe for wheel nuts ...  :P)

3.  I'll admit that the replacement studs that I fitted the last time were just standard supply items.  But they shouldn't need to be anything special, right?  And they hung on in the casing wonderfully ...  :D.

Maybe I should simply go back to using standard plated steel nuts?  I'll admit there's no reason for stainless, frankly ...

P.s It's the little bas88rd on the left side, close to the frame, that I hate.  Not enuf room to get the stud wrench in, you see.  Fark!  Out with the vice grips ...
 
as mentioned above there are good mechanical clamping and engineering reasons why studs are used, but everyone is forgetting to highlight, although mentioned in passing, that if you replace the suds with bolts, the the female threads in the bottom of your precious crancases will wear out.
CLEM
 
Hi Craig,

I have a lot of practical experience with stainless nuts/bolts, if you are 'picking up' removing them then yes, that is gauling - definitely.
The damage may have been done when doing the nut up, but once it 'bites' the grip gets stronger even when undoing (top tip if you feel rising torque when removing a fastener go the other way for a full turn to break the swarf chip and then go back the way you were).

I use a low strength Loctite thread locker on my filter cover studs with just a nip on the nut, no worries about undoing inadvertantly then.

There are loads and loads of anti-seize grease out there, Copperslip is a bit old hat now (I use Moly grease where possible).



 
CLEMTOG said:
as mentioned above there are good mechanical clamping and engineering reasons why studs are used, but everyone is forgetting to highlight, although mentioned in passing, that if you replace the suds with bolts, the the female threads in the bottom of your precious crancases will wear out.

Not if you drop the filter once every decade... like me. :D

Yes, this danger does exist.  Many primary covers come off more often than the filter plates, and their threads seem to hold up well enough.  A bit of ham-fistedness can quickly change that, though.

piet
 
SimonR501 said:
I have a lot of practical experience with stainless nuts/bolts, if you are 'picking up' removing them then yes, that is gauling - definitely.
Ta, Simon ...  (thumbup)

Ciao

Craig
 
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