Hi



I'vw been working on my bike for the past few weeks trying to remove the gearbox. I also decided to check the clutch. The components were stuck fast and I finally managed to remove the clutch.

unfortunately in my haste to remove the clutch I damaged the pins on the pressure ring (first cover under bolts)...doooh!

I have decided to replace the friction plate and the pressure ring but i have no idea how to balance the components. some claim it doesn't matter, but I know that BMW marked the plates for a reason...what happens when the pressure ring and pressure plate are replaced.

I also noticed a very light film of grease around the outer edge of the clutch components on the inside of the bellhousing. i cleaned the area and i had a look to try and figure where the oil or grease was originating.

i had a peek behind the clutch housing and it was dry.

i dont want to mess with the output shaft seal unless its absolutely necessary. i noticed a light film of grease covering the clutch input side of the gerbox. me thinks it's leaking from the gearbox.

anyway i have decided not to disturb the clutch housing and instead replace the clutch components. i also have the problem of the new components and how to balance them.

which type of grease do i use when installing the clutch components?

all suggestions are appreciated.



cheers

Hi Gabriel not sure about the balance but make sure you replace the clutch bolts with NEW ones as the old ones would of stretched

cheers Tony

Best thing to replace them with is a hex head bolt. They are a 7mm x 1mm thread and the only place I have been able to get them is REPCO they come in a blister pack and are made by Champion you find them on a rotating stand in the REPCO shops. It is worth using them as they dont strip the centre out when using a torque wrench like the low head socket head bolts that are the genuine thing.

not quite certain if I described the situaton accurately, but the clutch bolts were fine. The problem is the guide pins attached to the front friction plate. I bent two of the pins as I tried to remove it from the engine.

i now have to replace this item and I am not certain how one goes about balancing the two components when they are replaced.



cheers

There's no balancing of any of these clutch components, but you should always replace the one-time use clutch bolts and the O-ring under the centre flange nut. Keep in mind, too, that what ever uneven wear or score marks are on the pressure plates will be transferred quick smart to the new disc.

In my books it`s mentioned that it should be balancing marks on part 1,4,6 that should be spaced 120 degree from each other.

I haven`t noticed these marks, but maked my own before dismantling.

Have read several places on the net, about a lot of vibrations if this haven`t been followed.



Inge K.

If the oil is not behind the clutch then it has to be comming from the nut at the centre and that happenes if the O ring is shagged (east to have on a 20+ year bike). You need to replace the O ring and nut so you may as well replace the seal. Its a lot of work if it starts leaking shortly after which is highly likely after all it is the same age as the O ring you are replacing.

thanks for the responses. there seems to be difffering opinions regarding the balancing of the components.

i has a close look at the front and rear pressure plates and notices that although they are symmetrical, the front pressure plate has several round sections drilled into the outer surface. i also noticed that the clutch housing is not symmetrical. usually there is two holes for the bolts and one for the guide pins, but there is one section of the clutch housing which has additional holes. surely this would affect the components?

i wonder how BMW deals with this situation...

cheers

checked out k bikes forum and there was a thread regarding the clutch components. i noticed the pressure plate looked different to the one in my bike. the one pictured in the forum doesnt have the additional indentation marks....if that's the case i dont understand why the components are balanced. both pressure plates are symmetrical so why the markings?

i also noticed two red dots on the clutch nut? any ideas why.....

gabriel were the dots on the thread section ?

some times assemblers mark the threads with a spot of nail varnish ....works like locktight

extra drill marks /holes usually means the that part of assembly has been balenced ....or more correctly compensated for something in the manufacturing process .

it certainly would be good to mark the assembly before pulling it apart

i am a little concerned that the pins were bent .....but really shouldnt make that much difference ....as long as they are still there ...have you tried ..carefully bending them back into place?

the main reason for this is to maintain the original weight effect of the rotating assembly as a whole



if everything is still there...you may be just over complicating the whole deal with worry



hope this helps ....

HI



the pins on the rear friction plate must be perfectly straight or else it will be next to impossible to reattach it to the clutch housing..i tried..it was a tight fit...also important to remember that the front pressure plate (with the springs on the outer circumference) moves along the guide pins when the clutch disengages.

if the pins are not straight, it will be difficult for the front pressure plate to move along these pins.. i tried..it was very difficulty for me to disassemble the components.

any of the experts out there have the defiinitive answer to this problem?

these components are replaceable, therefore there must be a way to "balance" the components or are we perhaps exaggerating the idea of balancing the components......

there was a red dot on the end of the bolt and the nut..two small perfect dots......

i will try and take a photo and upload it..if only i knew how to do it...

cheers.....

The recommended solution to BMW mechanics for the situation you're in was to replace the clutch assembly as a complete unit. That's what I've read (I'm not a mechanic). For the service department, time is money.

Since we don't have access to the factory equipment used to balance the clutch parts, the only means open to the home mechanic to achieve a balanced installation is trial-and-error. It will be necessary to disassemble the transmission housing and reorient the clutch components 1,4 and 6 relative to each other if you find that you have vibration upon reassembly. This is very labour intensive and may take up to six tries to achieve balance (theoretically of course). That is why most home mechanics emphasize marking the components prior to first disassembly.

There are supposed to be paint marks on the clutch parts (not the drive shaft and clutch nut) put there by the factory. Look very carefully for those marks. I disassembled and replaced my rear seal this summer and never noticed red dots on the clutch nut.

The marks have been earlier noted as white or yellowish paint 'licks'. I understand they have marked the heaviest side, so putting it together with the three paint marks 120 degrees from each other should balance it out best.

Rene, you would be correct if the original parts were being mated back together. However, the OP has stated that he purchased a new clutch pressure plate, part 4. All bets are off now that the two pieces of the clutch pressure assembly are no longer factory matched.

I don't know that the assembly can be assembled in a balanced form. The two parts, 4 and 6 in the diagram above, are balanced as a unit and separately from the clutch basket, part 1. The OP could try setting the factory marks 120 degrees from each other (assuming they can be found). If I were in this position, however, I'd either try to straighten the pins on the original pressure plate and reuse it. Or I would try to purchase a used pressure plate assembly consisting of the factory matched parts 4 and 6 from a breaker's yard.

Do not try to straighten the pins they are heat treated and hardened, if they don't fracture they will be damaged and will most likely fail in service. You will find that they will be a standard size and you should be able to purchase generic pins and alter the length.

good tip k freak ...are they rolled pins ?

charlie99 wrote:good tip k freak ...are they rolled pins ?

No not rolled more like a roller bearing roller.

Ah, didn't know that. Thanks. Pin replacement is a better idea in light of that bit of knowledge.

Thanks for the replies. The pins cannot be straightened and they appear to be "welded" to the face of the pressure plate. where would one begin trying to replace the pins.

i will consider contacting Motobins and motoworks and try to source a second hand set of clutch components (front and rear pressure plates) or compare a replacement plate with my plate and try and match the markings......

cheers

The pins are a press fit into one side and a size fit to the other. You could see a local engineering shop to source the pins, you may be able to use some rollers from a bearing assy. I have a few clutch assemblys with pins if you want one. Semd a PM for details. Depending where you are in Oz you may be able to come get them.