D.I.Y. Cam Chain Replacement

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EDIT: See Page 4, POST 56 to get to the beginning of actual tear down.
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EDIT: See Page 10, POST 141: chadams has a master link solution in progress.
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EDIT: See Page 11, POST 161: Joelwisman offers tech insight to cam chain stretch.
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EDIT: See Page 17, POST 336: TheJoker shows video of Chadams master link solution.
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EDIT: See Page 19, POST 366: Wacholek opines design improvements needed for OEM tensioner
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So tech says chain is stretched slightly.

No measurement but I trust the eval. She&'s running rough and does have a chatter at idle when hot.

What to do? Well, Joel says its an 8 hour job. I'll give a 24:1 transposition and give it a whirl.

I have the maintenance DVD. (Haven't looked at it yet.) I ordered the Haynes Manual yesterday.


Parts went on order today:


Item Part Quantity Part Number Cost
3 GASKET RIGHT 1 11147670688 $15.00

ENGINE RIGHT

1


Item Part Quantity Part Number Cost
7 Gasket set, cylinder 1 11128520621 $68.97
head cover

VALVE COVER

2


Item Part Quantity Part Number Cost
6 GEAR WHEEL 2 11317708198 $42.01 EDIT: DID NOT NEED THE GEARS.
8 GUIDE RAIL 1 11317690494 $7.74
11 TIMING CHAIN 1 11317690475 $84.39
12 CHAIN TENSIONER 1 11317690493 $10.80
7 Bearing screw 1 11317676592 $4.98 EDIT: REUSED OLD SCREW.

TIMING GEAR

3


Item Part Quantity Part Number Cost
1 GASKET LEFT 1 11117707906 $24.10

ENGINE LEFT

4


Item Part Quantity Part Number Cost
07 Gasket, oil pan 1 11117707905 $28.93


OIL PAN

5



Plus a tube of sealant.


I have torque wrenches. I have a garage. I have stayed at Holiday Inn Express this month....What am I missing?


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EDIT: I reused all the old seals and o-rings but I should have also orded:
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exhaust header flange gaskets
cam sensor o-ring
coolant lines o-rings
valve cover o-rings
out put shaft seal for counter sprocket
shaft seal for gear shift

Will be watching closely as mine's making more and more noise all the time.

any possibility you can take pics of the project and caption the process?

I plan to. Unless of course I screw it up then I'll disavow all knowledge of the event....

Step by Glorious step.
with photos.
good and bad.

and don't forget the beer.

This could be really interesting...

Just curious, what is the mileage on this engine? Is the chain worm beyond the limits that the tensioner can compensate for?
Is there a problem with your tensioner, too?
Cam chains in Cheap Japanese Motorcycles used to run fine for 100,000 miles and more.
But then again so did wheel bearings.

92,000miles

Yes

Yes. Tensioner was bad. It has been replaced. (34,000 & 88,000) Suspect this was the root cause of the cam chain stretch.

Ich verstehe nicht

I had toyed with the idea of contacting BMW NA and offering a high-mileage GS for QA historical data . But.....I'd rather be riding and I want this chain fixed so I can get back to it.

Have you heard anything about a new design a CAM chain tensioners? How hard are they to replace? Symptoms of the tensioner going bad? How many fibers in a shredded wheat biscuit?


Sorry for the questions, just curious.

No

The current one just screws into place. No fuss. [EDIT: I did reload it with oil prior to install.]

African or European?

Huh, I wonder if replacing the tensioner every 20k or so miles would be good preventative maintenance....

Damn Nick, I didn't know you had THAT many miles on it! :eek1

Is there any reason why it wouldn't be possible to replace the chain without taking the whole engine apart, e.g. split it and put in a master link? I would think that there is nothing unique about the BMW chain, so it would be a matter of finding an industrial supplier that can match the pitch, roller diameter etc. Or maybe from another bike?

Cheers,
Lukas

PS: Stator has been rebuilt and is now on the way to me. Cost $165 + shipping so not too bad. I will post some pics so we can see the quality and compare it to the Electrosport offering.

Yeah, I get that a lot. What can I say, I like the bike.

Because the OEM chain is continuous, the engine must be cracked to install a new one. While I did consider trying to find a master link solution, the additional problem is internal wear on the guides. If you look at the pics (Timing Gear #12 & 17), the guide rail and tensioner are likely worn and must be inspected. Since I'm in there anyway, I'll just replace them. Plus, I don't like being the crash test dummy in the master link conversation even if I could find one.

Glad that appears to have worked out. Keep us informed. I have a feeling more will be needed.

Lost Rider actually commented that this might be a good idea every 30,000. Until this widget gets re-engineered, I think that will be my new policy.

Is it the spring or the actual tensioner piece that you are contemplating replacing on a regular basis?
Am I correct in thinking it is a simple arrangement where the spring rests with pressure on the tensioner piece?
Or is the tensioner piece operating hydraulicly or something different?
What is the easiest way to get at it? I have the RepRom but it just shows where the thing is hiding and not how to
get at it in the part about replacing the tensioner.

Spring puts tension on the tensioner and hydraulic pressure provides damping. I believe it is the hydraulic portion that is failing and causing the issue. This is based upon comments from the tech that pulled the last one and showed the part was failing to maintain oil and thereby not working.

In the pic labeled Timing Gear, the item that everyone refers to as the cam chain tensioner is on the right hand side of the pic #14, 15, 16,& 17.

Sweeeeet wrenching......I'm in.

HF

Awsome.....watching this one closely!

Me too. I want to do my own when it is time and save $1,000 in labor.
I do all my dirt bike cam chains but this beast looks like it will take twice as long to do.
Go DieselBoy!