Help me with the parts list for the K75

[Batan]

The newly purchased K75S is still stored at the POs place. I will be getting it in the next few weeks. But I want to put together a parts list as the bike needs a lot of service.
It leaksfrom
- blown fork seal on one side so it needs new ones
- "front engine cover", this was a note from a shop. Not sure what they mean. Timing cover? Maybe.
- it is wet around the bottom week hole. I think it's engine oil so it would indicate the clutch o-ring?
- sight glass is leaking as well

I will be doing all the fluid services and I need to lube all the splines. The bike has 70k miles on it.

What seals should I order? I see they are not expensive so I might as well order some before I even get the bike and take the bottom fairing off to see.

[The Mighty Gryphon]

Before I go into the fork seal I would see if there is a bit of dirt stuck in the seal's lip.  This little tool can do the job.  You can make one from the side of a soda bottle.

https://sealmate.net/products/seal-mate

I use Automatic transmission fluid in my forks.  It has the right viscosity, doesn't cost a lot and as a bonus it has conditioners to soften up old seals.

The timing chain cover is known to leak at the point where it joins the valve/cam cover.  This is cause by a slight gap where the various surfaces come together.  It is fixed by putting a little bit of silicone sealer on the mating surface to fill the gap. 

The clutch o-ring is a common source of leaks.  They harden up after 30+ years.  The rear main seal can be replaced at the same time.  There is a trick to getting it installed to the correct depth.  I use a bit of cardboard from a cereal box that is cut out to fit around the seal while I tap it into the block.  The cardboard stops the wood block I am driving the seal with so the seal stands proud by approximately 0.5mm.  I use a Viton seal and o-ring.

[Batan]

Before I go into the fork seal I would see if there is a bit of dirt stuck in the seal's lip.  This little tool can do the job.  You can make one from the side of a soda bottle.

https://sealmate.net/products/seal-mate

I use Automatic transmission fluid in my forks.  It has the right viscosity, doesn't cost a lot and as a bonus it has conditioners to soften up old seals.

The timing chain cover is known to leak at the point where it joins the valve/cam cover.  This is cause by a slight gap where the various surfaces come together.  It is fixed by putting a little bit of silicone sealer on the mating surface to fill the gap. 

The clutch o-ring is a common source of leaks.  They harden up after 30+ years.  The rear main seal can be replaced at the same time.  There is a trick to getting it installed to the correct depth.  I use a bit of cardboard from a cereal box that is cut out to fit around the seal while I tap it into the block.  The cardboard stops the wood block I am driving the seal with so the seal stands proud by approximately 0.5mm.  I use a Viton seal and o-ring.

Thank you!

[The Mighty Gryphon]

There are numerous threads here on the items you are asking about with lots of good information.  Almost anything you come across on your bike has been beaten to death here.  When you are ready to tackle these items be sure to start threads here that will allow you to ask questions and get advice.  There are many here who would be happy to help.

[sooprvylyn]

For that rear main seal....if you have access to a 3d printer...you can print one of these tools for seating the seal properly:

https://www.thingiverse.com/thing:4459988/files


I used this recently on my rear main seal and worked perfectly.


I still need to replace the seals on my gearbox myself.

[Batan]

For that rear main seal....if you have access to a 3d printer...you can print one of these tools for seating the seal properly:

https://www.thingiverse.com/thing:4459988/files


I used this recently on my rear main seal and worked perfectly.


I still need to replace the seals on my gearbox myself.

OMG, you rock!!! I was going to ask someone to measure the tool for me so I can model and print it! 

[sooprvylyn]

In addition, you can fabricate the tools for removing the tranny from the clutch housing using these:  https://www.amazon.com/gp/product/B01LYNG7ME/ref=ppx_yo_dt_b_search_asin_title?ie=UTF8&psc=1

You need to cut one end of the threading off of 2 of these.  The one used on the left side of the tranny will need to be around 3" long, the other one can be the full length.  They act as a guide to make it easier to remove and re-install the gearbox wthout bending the clutch actuator pin(which is like 1/4" thick and can bend easily.

In addition you may need a clutch alignment tool cuz you need to remove the clutch to access the rear man seal...its kinda finicky and made of aluminum so be gentle when using it.: https://www.ebay.com/itm/276099967158?chn=ps&norover=1&mkevt=1&mkrid=711-117182-37290-0&mkcid=2&mkscid=101&itemid=276099967158&targetid=1529493985102&device=c&mktype=pla&googleloc=9028292&poi=&campaignid=19851828444&mkgroupid=145880009014&rlsatarget=pla-1529493985102&abcId=9307249&merchantid=114834093&gclid=CjwKCAiA75itBhA6EiwAkho9e8GwcoZFrGPYw6qTH5HPxu0rgk-uOTqYdOma_BFGqi_K4bxXmrnp2RoCL_wQAvD_BwE

Lastly, make sure you mark your clutch components clearly for reassembly  BEFORE you disassemble...use a sharpy.  They are a balanced unit so the parts have to go back together in the exact same position as they were before you removed them or you'll end up with a gnarly shake when the engine spins. 

The clutch bolts are stretch bolts, so if you use OEM bolts make sure you know the torque specs and get everything perfectly aligned. ONce you torque em you cant unscreww and reuse em again, they'l be stretched and useless to reuse.  I said fuck it on those stretch bolts and just used hardened bolts with some red locktite...iirc they are M5 bolts, might be m6, just measure the old ones when you remove em.  The lock washers should also be replaced...but with the locktight and hardened bolts they arent so important, Important if you use the OEM stretch bolts tho.

[sooprvylyn]

looks like i linked an r-bike clutch tool.  Here is the k-bike one----looks like its probably the exact same but to be safe use this one:

https://www.ebay.com/itm/276208634692?chn=ps&norover=1&mkevt=1&mkrid=711-117182-37290-0&mkcid=2&mkscid=101&itemid=276208634692&targetid=1645685073568&device=c&mktype=pla&googleloc=9028292&poi=&campaignid=20133407470&mkgroupid=147476396765&rlsatarget=pla-1645685073568&abcId=9312979&merchantid=114834093&gclid=CjwKCAiA75itBhA6EiwAkho9e5z70uCNN-3NPqolnzAJVs-ZE5mdNuqzDRO9Tq4LZRNcppve3if2whoC6xEQAvD_BwE

[sooprvylyn]

Im happy to measure my clutch tool if you want.  I might be a little reluctant to use a 3d printed one for this.  If you do, make sure its not brittle material or else you may have trouble.  For $22 for the one I linked its worth just buying the alloy one that wont snap off where you dont want it to.

Dont forget to get the o-ring needed for reassembly of the clutch.  its cheap but you need it.  check the parts fiche, you'll need to order from a supplier, its around 3/4" rubber o-ring.  Part # 11 21 1 460 46   O-RING - 19X4

Its part 11 on this diagram:

https://shop.maxbmw.com/fiche/DiagramsMain.aspx?vid=51711&diagram=16_0242&partnumber=46637686746


IIRC everything else except for this o-ring and the clutch bolts were reusable.

[sooprvylyn]

dang, it didnt link the right diagram for that o-ring. Scroll to the clutch single parts diagram, its part #11 on that

Also I linked the k1100 parts fiche, but this o-ring is the same on k-75 so...

[Batan]

Im happy to measure my clutch tool if you want.  I might be a little reluctant to use a 3d printed one for this.  If you do, make sure its not brittle material or else you may have trouble.  For $22 for the one I linked its worth just buying the alloy one that wont snap off where you dont want it to.

Dont forget to get the o-ring needed for reassembly of the clutch.  its cheap but you need it.  check the parts fiche, you'll need to order from a supplier, its around 3/4" rubber o-ring.  Part # 11 21 1 460 46   O-RING - 19X4

Its part 11 on this diagram:

https://shop.maxbmw.com/fiche/DiagramsMain.aspx?vid=51711&diagram=16_0242&partnumber=46637686746


IIRC everything else except for this o-ring and the clutch bolts were reusable.

Brilliant, thanks again. The clutch tool was next on my list. And I agree, it is too thin for 3D printing, I won't risk the headache.

[frankenduck]

The R and K clutch holder tools are the same.

But you don't need one. You can just use a block of wood to keep the clutch housing from turning.



And you don't need a clutch centering tool. You  can use the transmission for that.

https://www.kbikeparts.com/classickbikes.com/ckb.tech/0.ckb.tech.files/clutchnospecial/clutchnospecial.htm

I have the tools but don't even use them.

[Batan]

The R and K clutch holder tools are the same.

But you don't need one. You can just use a block of wood to keep the clutch housing from turning.



And you don't need a clutch centering tool. You  can use the transmission for that.

https://www.kbikeparts.com/classickbikes.com/ckb.tech/0.ckb.tech.files/clutchnospecial/clutchnospecial.htm

I have the tools but don't even use them.

Oh you don't?
Might be a good thing as the centering tool price climbs because I'm in Canada. And it's not like I'll be usinf it all the time.

[sooprvylyn]

So the centering tool is NOT related to spinning of the clutch housing.  it is there to center your clutch  friction plate and spring after you reinstall the clutch housing cover and BEFORE you tighten the bolts all the way.  The clutch housing will spin when you try to unbolt it, so a wood block like that picture is great for keeping it from doing so, also an appropriately sized socket works for that.  This is not what the clutch tool is for tho.

Since you must completely remove the clutch and housing to access the rear main seal that means you will 100% have to completely reinstall the clutch.  That picture you see up there is the clutch housing AFTER completely removing the clutch(which can fall into like 4 pieces on removal, so mark it well).  The friction plate and spring are loose in there and will not autocenter, they must be manually centered on reinstall, near perfectly.

You may not "need" the clutch centering tool if you have really really good eyes, and an awl.  You will need to center the spring and the clutch plate perfectly to reinstall the transmission.  Its a bit finicky, but doable if you are patient and do a few test fits of the tranny before torquing the bolts all the way.  It needs to be reasonably precise.

If you really really dont want to buy that tool, I can measure my tool and give you the specs to 3d print it.  If you do 3d-print the tool, be very very gentle with it and align before torquing down your clutch bolts to ensure center....and its smart to test fit that tranny before torquing them all the way down.  The "pin" of the clutch tool fits into the hole in the center of that drive shaft. You DEFINITELY do not want 3d plastic snapping off in there.  At the least, make sure the fit of that part has good play in case it does and you need to fish it out.


The precision is not tooling shop precise, but it is reasonably precise so the tool helps a lot...but can be done with good eyes too.  Once reinstalled you can actuate the clutch lever and the clutch pin will move the spring and friction plate into perfect alignment.  basically if you can get the tranny back on with the clutchpin installed in the tranny then you are good.

[sooprvylyn]

The clutch pin is kinda delicate.  Like i said, its only about 1/4" diameter where it enters the clutch center shaft.  The pin is also made of aluminum with a couple pressed in steel parts on each end.  Its delicate and could bend pretty easily. 


Definitely a good idea to make those tranny alignment tools from those threaded rods i linked to help you align the tranny.  That tranny weighs like 50lbs and that will easily bend that clutch pin if you go in crooked or drop the tranny as you attempt to seat it.  The pins will 100% prevent that possibility and they are cheap.  Much cheaper than replacing that clutch pin.


The centering tool is super helpful to use, but not strictly speaking 100% neccessary if you are a bad ass with really good eyes and some patience.

[sooprvylyn]

This is what the clutch tool does...see that thing in the center of the clutch plate.  Its aligning the friction plate with the spring so that the clutch pin and gear splines will line up right.

You need really badass eyes, and some trial and error, to make it work without that tool.

[Batan]

This is what the clutch tool does...see that thing in the center of the clutch plate.  Its aligning the friction plate with the spring so that the clutch pin and gear splines will line up right.

You need really badass eyes, and some trial and error, to make it work without that tool.

Thank you. I have used a clutch tool before, but they have always been plastic. Maybe I should model one based on your measurements and print it sideways for strength. That would probably work.
(And then I can make it available)

[Batan]

The clutch pin is kinda delicate.  Like i said, its only about 1/4" diameter where it enters the clutch center shaft.  The pin is also made of aluminum with a couple pressed in steel parts on each end.  Its delicate and could bend pretty easily. 


Definitely a good idea to make those tranny alignment tools from those threaded rods i linked to help you align the tranny.  That tranny weighs like 50lbs and that will easily bend that clutch pin if you go in crooked or drop the tranny as you attempt to seat it.  The pins will 100% prevent that possibility and they are cheap.  Much cheaper than replacing that clutch pin.


The centering tool is super helpful to use, but not strictly speaking 100% neccessary if you are a bad ass with really good eyes and some patience.

Would definitely make the tools alignment pins.

[sooprvylyn]

I do see what frankenduck is talking about.  It can work.  in order to do it you must remove the clutch boot off the back of the tranny to remove the pin.  it slides all the way through the tranny without any detent so this can work.  remove it before installing the tranny for fit, then install to center, then remove the pin again BEFORE taking the tranny off again to tighten the clutch bolts.

You really should the tranny alignment pins for this to work as you MUST pull that tranny back off perfectly level to maintain the position of the clutch before tightening the clutch bolts.  Also REMOVE THAT PUSHROD(CLUTCH PIN) BEFORE YOU REMOVE THE TRANNY AGAIN.  That pushrod should not be in the tranny at all when mount it to the clutch bell housing if you do it without the tool.  YOU RISK BENDING THAT PIN if you leave it in.

I will go ahead and get you measurements of the tool when I get home so you have access to them. 

[Batan]

I do see what frankenduck is talking about.  It can work.  in order to do it you must remove the clutch boot off the back of the tranny to remove the pin.  it slides all the way through the tranny without any detent so this can work.  remove it before installing the tranny for fit, then install to center, then remove the pin again BEFORE taking the tranny off again to tighten the clutch bolts.

You really should the tranny alignment pins for this to work as you MUST pull that tranny back off perfectly level to maintain the position of the clutch before tightening the clutch bolts.  Also REMOVE THAT PUSHROD(CLUTCH PIN) BEFORE YOU REMOVE THE TRANNY AGAIN.  That pushrod should not be in the tranny at all when mount it to the clutch bell housing if you do it without the tool.  YOU RISK BENDING THAT PIN if you leave it in.

I will go ahead and get you measurements of the tool when I get home so you have access to them.

Brilliant, thank you.

[sooprvylyn]

Here are a few pics

First one is the rear mains seal tool to give an idea of scale

2 and 3 are pics of the tranny pins. The shorter pin is for the left side.

Rest of pics are the centering tool

[sooprvylyn]

Forgot this one....battery died, but it's not a super critical measurement anyway so you can do 12mm and it's fine

[sooprvylyn]

These are the 2 holes for the tranny alignment tools. Left side is shorter pin.

You can totally cut them both short, the right side doesn't have anything in the way tho, but the Left side does so needs to be short.

[Batan]

These are the 2 holes for the tranny alignment tools. Left side is shorter pin.

You can totally cut them both short, the right side doesn't have anything in the way tho, but the Left side does so needs to be short.

Super helpful, thanks again!

Printed the main seal tool, one down.

[frankenduck]

K bike transmissions do not weigh 50 lbs. That's just silly. They weight less than 35 pounds.

I just use hex head M8x100 bolts to install transmissions. Makes it a lot easier to get the transmission up near the bellhousing. Then I put a couple of hex head M8s in the two bottom holes to support it in the right place while installing the top bolts. Much easier to get hex head bolts in and out with a ratchet.