What size is the crankshaft end nut?

Lord Snooty

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2010 1200 GSA, I'm replacing the alternator belt but I don't have a socket big enough to get onto the nut on the crankshaft pulley to turn it. My largest socket is 32mm and is not big enought so what size spanner or socket do I need?
 
I always use a large adjustable for that one, I wrap a load of insulating tape on the handle and that gives a better 'bite' on the new belt as you wind it on..

Roger.
 
2010 1200 GSA, I'm replacing the alternator belt but I don't have a socket big enough to get onto the nut on the crankshaft pulley to turn it. My largest socket is 32mm and is not big enought so what size spanner or socket do I need?

Do you have the correct belt ?? 4PK592 ELAST <- This bit is most important

If your belt hasn;t got it STOP and send it back and contact local motor factors and get them to order you one
 
One that fits; dooh

I used a cranked spanner for a Ford Cologne V6 fan, iirc 36mm

Sent from my SM-G925F using Tapatalk

Thanks, I never thought of using one that fits I just thought I'd waste my time asking the question on here :blast

So, are you confirming that it is 36mm?
 
Do you have the correct belt ?? 4PK592 ELAST <- This bit is most important

If your belt hasn;t got it STOP and send it back and contact local motor factors and get them to order you one

I have no idea Doc, it is in the garage, I ordered it from James Sherlocks and they are BMW parts specialist so they should know what they are doing. Will that information be printed on the belt?
 
I thought it was 34mm

I have both a 32 and a 36 and one was too big and one too small

there's a special tool to fit stretch belts, on the alternator belt it was much harder than I expected it to be, no point taking off a good but old belt and then ripping the new one forcing on with a socket and a screw driver.. without the tool you need someone to help
 
I thought it was 34mm

I have both a 32 and a 36 and one was too big and one too small

there's a special tool to fit stretch belts, on the alternator belt it was much harder than I expected it to be, no point taking off a good but old belt and then ripping the new one forcing on with a socket and a screw driver.. without the tool you need someone to help

Without the tool, you can use some old plastic milk bottle material as shims under the new belt as you rotate it on, then turn the crank a bit more to remove the shims/fit the belt into its grooves.
 
The Elast as you may have gathered means its a stretch belt

If it does not have ELAST on it the fucker will be a Kevlar reinforced nightmare

Should have the part number on the packaging
 
The Elast as you may have gathered means its a stretch belt

If it does not have ELAST on it the fucker will be a Kevlar reinforced nightmare

Should have the part number on the packaging

Doc, I have just checked and it has 4PK582 on it but not ELAST, why is it a nightmare?
 
It's listed on RealOEM as a 4PK582, but that's the BMW designation and the actual part you need is the 4PK 592 ELAST as others have said which, confusingly, is actually 582 length. It's annoying BMW do that. These guys tend to be quick at despatching:
https://www.ebay.co.uk/itm/4PK592EL...783916?hash=item4658381fec:g:g5kAAOSwONBZCYVq

You don't need a special tool. Plastic bottle and large adjustable work fine. Engine bars can be a faff though
 
Just make sure what you put on matches what came off it....

People do realise that a Denso alternator bike has a different belt length to a Bosch alternator one ?

Roger...
 
Take out the two main spark plugs so the engine rotates without any compression and it’s a doddle to change.
 
I asked ContiTech about the different belt designations, they sent this reply -

""The Elast designation on a Contitech belt is to show that it has elastic cord members in the belt, this allows the belt to be fitted by stretching into place without any tensioning device or moveable pulleys. Not all manufacturers, especially OE, clearly show on the belt label if the belt is elastic and this can cause confusion. This is especially important as Traditional and Elast belts cannot be interchanged.

To add to the confusion some manufacturers use the production length as the part number and others use the fitted (stretched) length. Because of this it is important to use the cataloguing system to identify the correct belt and not to use the numbers from the old belt.

The Contitech belt will show for information both production and fitted lengths so the belt that you have will be:

4 [number of ribs] PK [rib profile designation] 592 [fitted length] (582) [production length] ELAST [elastic belt brand name]

I have been told previously by our product managers that BMW always gives the production length for elastic belts while we always give the fitted length as our primary number.

The BMW belt 4PK592 equals our 4PK611 (592) ELAST. Production length in brackets.
The BMW belt 4PK582 equals our 4PK592 (582) ELAST. Production length in brackets

Please also note that in many cases a special tool is required to install the Elast belt correctly without damaging the belt or pulleys.

I hope this helps you to identify the correct belt for your bike."


As Steptoe says, with the main plugs out, it's a simple job.

Pete
 
Milleplod,
Thanks a thousand for posting that explanation, very clear!
The elastic belt sure beats faffing with alternator bolts as on 1150.
Dead easy to fit, using back wheel or even starter to kick engine if no spanner.
Bin
 
Credit where credit is due, that's a great response from Contitech
 
Mine is a Contitech belt but does not have the ELAST designation so I intend to get back to James Sherlock and ask them to replace it with the ELAST version.

Thanks all, the information and help has been fantastic.;)
 
Ditto Bin Ridin - just put remove the plugs, put the bike on 6th and use the back wheel to turn he engine. You don't need a socket. I use my foot to turn the back wheel while holding the belt with my hands. ELAST belt goes in easy.
 


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