Author Topic: Oh CHIT - Lack of Spline Goodness  (Read 28367 times)

Offline 2000rsv

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Oh CHIT - Lack of Spline Goodness
« on: February 16, 2013, 02:43:32 PM »
Well, I picked up an '86 K75C last summer and my son rode it around a bit.  Only has 21,600 miles on it.  Getting around to doing a spline lube and I found this on the drive shaft.  Sorry about the bouncy video.  Was using my HF Centech Inspection Camera.



OK, how screwed am I?

New (per MAX BMW website) is $400.  From searching on here Bruno rebuild is $800. 

Suggestions?  Recommendations?
AMA 1097757, IBA 33089, TS 700
2009 GSA, 2012 K1600GT, 2008 KLR650, '86 BMW K75C, and always a couple of projects

Offline frankenduck

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Re: Oh CHIT - Lack of Spline Goodness
« Reply #1 on: February 16, 2013, 03:51:15 PM »
Those are pretty worn.

Splientology
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Offline 2000rsv

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Re: Oh CHIT - Lack of Spline Goodness
« Reply #2 on: February 16, 2013, 05:02:29 PM »
I have read thru the Splinetology several times.  Looks like I am out $400.

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Offline Scott_

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Re: Oh CHIT - Lack of Spline Goodness
« Reply #3 on: February 16, 2013, 08:48:40 PM »
Consider yourself lucky, you are home, in controlled conditions.
Better than on the side of the road, in the middle of who knows where......spending how much more to get it home......
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Offline frankenduck

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Re: Oh CHIT - Lack of Spline Goodness
« Reply #4 on: February 16, 2013, 08:57:02 PM »
Consider yourself lucky, you are home, in controlled conditions.
Better than on the side of the road, in the middle of who knows where......spending how much more to get it home......

Or 1,600 miles from home at a gas station in Pipestone, MN. (Clutch splines.)



Still beats crashing though.
Once I had a Collie pup. Dug a hole and covered him up. Now I sit there by the hour. Waiting for a Collie-flower.
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Offline 2000rsv

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Re: Oh CHIT - Lack of Spline Goodness
« Reply #5 on: February 17, 2013, 12:01:06 AM »
Haven't gotten to the clutch yet.  Have the swing arm off and removed the drive shaft.  Splines on the xmission output were still wet with lube and looked brand new.  That's good.  Hoping to do some work tomorrow on getting the transmission off so I can look at the clutch.

There is a sensor of some kind on the rear of the transmission.  It is round with two wired coming out of it.  Is this the neutral switch?  It appears to be cracked.  However, the neutral light never had a problem coming on nor did I have trouble starting due to it not being in neutral.

Few questions about this sensor (looked it up on Max's - $106.00 - ouch)
1: What does it do?
2: Should I leave it alone or clean it up and fill the crack with RTV?
3: Should it be replaced?
4: Can I jumper the two wires to bypass it if I needed to?
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Offline motodude

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Re: Oh CHIT - Lack of Spline Goodness
« Reply #6 on: February 17, 2013, 12:19:41 AM »
Consider yourself lucky, you are home, in controlled conditions.
Better than on the side of the road, in the middle of who knows where......spending how much more to get it home......

Casper, WY.  Then the tow-truck strap breaks on the way to the Honda dealer (bike falls over on the truck).  Then it takes two days to get a new drive shaft from Denver (final drive splines were, "good enough" given brand-new drive-shaft splines).  Good times.
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Re: Oh CHIT - Lack of Spline Goodness
« Reply #7 on: February 17, 2013, 05:00:09 AM »

I believe that device is the gear position sensor for the dash indicator.

Offline billday

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Re: Oh CHIT - Lack of Spline Goodness
« Reply #8 on: February 17, 2013, 08:56:06 AM »
Yes it's the gear position indicator switch. If it's working leave it alone, no need to take it off the tranny for any of the work you're doing.
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Offline 2000rsv

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Re: Oh CHIT - Lack of Spline Goodness
« Reply #9 on: February 17, 2013, 09:27:44 AM »
OK, Thank you.  If the gear indicator quits working, it isn't that big of deal (at least not $106 big).  None of my other bikes have ever had one.

OK, let's what surprises today brings as I tear into it further.
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2009 GSA, 2012 K1600GT, 2008 KLR650, '86 BMW K75C, and always a couple of projects

Offline Inge K.

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Re: Oh CHIT - Lack of Spline Goodness
« Reply #10 on: February 17, 2013, 09:47:23 AM »
If the gear indicator quits working, it isn't that big of deal

If it quits working, you need to pull the clutch to start.
Some have cleaned the switch housing, and covered the whole housing outside with silicone sealant......

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Offline 2000rsv

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Re: Oh CHIT - Lack of Spline Goodness
« Reply #11 on: February 17, 2013, 09:59:21 AM »
Ahh, so it is the neutral indicator for the starting logic also.  That makes a difference.  Will likely leave it alone.
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Offline frankenduck

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Re: Oh CHIT - Lack of Spline Goodness
« Reply #12 on: February 17, 2013, 10:26:06 AM »
The circuit that lights the N indicator sends power to the start button.
Once I had a Collie pup. Dug a hole and covered him up. Now I sit there by the hour. Waiting for a Collie-flower.
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Offline 2000rsv

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Re: Oh CHIT - Lack of Spline Goodness
« Reply #13 on: February 17, 2013, 11:01:00 AM »
The circuit that lights the N indicator sends power to the start button.

Does that circuit include this transmission sensor?
AMA 1097757, IBA 33089, TS 700
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Offline frankenduck

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Re: Oh CHIT - Lack of Spline Goodness
« Reply #14 on: February 17, 2013, 11:05:01 AM »
Once I had a Collie pup. Dug a hole and covered him up. Now I sit there by the hour. Waiting for a Collie-flower.
New to K bikes? Click here.
K Bike Maintenance & Mods: Click here.
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Offline 2000rsv

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Re: Oh CHIT - Lack of Spline Goodness
« Reply #15 on: February 17, 2013, 02:38:16 PM »
OK, kept digging into the bike and found the transmission input and output splines to both be in great condition. :2thumbup:

Was having some clutch slipping last fall so I was going to see what the clutch looks like.  Was worried the O-Ring went out and got the disc wet or something.  Not so.

Having never worked on a BMW style single disc clutch before, I still feel this clutch friction disc is in sad shape.  Measuring the thickness in various places, it went from 0.174 to -.185 inches (don't have a metric micrometer).  Manual says anything under 0.177 needs replaced.  Therefore, it's gone.

Interestingly, the rear cover has rust all over the outside.  Coupled with that, the friction disc surface looks strange.  Almost like there was water in the clutch area (perhaps condensation).  Any input?

The O-Ring looks in good shape but I will be replacing it anyway since I am already in there and it is likely 27 years old.

Got to say, clutches on Japanese machines are a whole lot easier to deal with.

The clutch disc:


Close up of clutch disc:


Transmission input splines:


K75 feelings particularly naked:
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Offline frankenduck

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Re: Oh CHIT - Lack of Spline Goodness
« Reply #16 on: February 17, 2013, 02:51:30 PM »
If the bike has spent a lot of time in a wet climate then water vapor gets in the bellhousing so it's not uncommon for the rear pressure plate to have some rust on it.

Yes, 0.177" is the wear limit for k bike clutch plates.

Good idea to replace the O-ring while you have the clutch off. :2thumbup:
Once I had a Collie pup. Dug a hole and covered him up. Now I sit there by the hour. Waiting for a Collie-flower.
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Offline 2000rsv

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Re: Oh CHIT - Lack of Spline Goodness
« Reply #17 on: February 17, 2013, 02:57:35 PM »
The fiche from Max's calls out the clutch housing main nut as a one use item, as well as the spacer between the nut and the O-ring.  It also calls out to replace the 6 clamping cap screws and star washers.

The nut is a specially deformed nut to stay locked on the shaft.  I could see replacing that (maybe).  The spacer between the nut and O-ring?  That's ridiculous to replace that.

The cap screws?  I'm going to re-use.  The star washers?  4 of them were broken anyway.  Will replace from the local hardware store.

Let me know if I am on the wrong track with these decisions.
AMA 1097757, IBA 33089, TS 700
2009 GSA, 2012 K1600GT, 2008 KLR650, '86 BMW K75C, and always a couple of projects

Offline frankenduck

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Re: Oh CHIT - Lack of Spline Goodness
« Reply #18 on: February 17, 2013, 03:12:25 PM »
I've re-used all of the hardware on several bikes with no issues.

You might want to consider using hex head bolts for the six bolts.  Will make them easier to get off next time.

I put some grease on the three rods and use anti-size on the 6 bolts to make it easier if I have to go in there again.
Once I had a Collie pup. Dug a hole and covered him up. Now I sit there by the hour. Waiting for a Collie-flower.
New to K bikes? Click here.
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Offline 2000rsv

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Re: Oh CHIT - Lack of Spline Goodness
« Reply #19 on: February 17, 2013, 03:23:17 PM »
Just ordered all the parts from Countryside BMW and saved over $100 with the Motobrick discount code.  You rock!!

Now, I hope I will not have to 'save' this much money in the future.
AMA 1097757, IBA 33089, TS 700
2009 GSA, 2012 K1600GT, 2008 KLR650, '86 BMW K75C, and always a couple of projects

Offline frankenduck

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Re: Oh CHIT - Lack of Spline Goodness
« Reply #20 on: February 17, 2013, 03:27:50 PM »
What code did you use?
Once I had a Collie pup. Dug a hole and covered him up. Now I sit there by the hour. Waiting for a Collie-flower.
New to K bikes? Click here.
K Bike Maintenance & Mods: Click here.
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Offline 2000rsv

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Re: Oh CHIT - Lack of Spline Goodness
« Reply #21 on: February 17, 2013, 03:36:41 PM »
Promo15.  Tried Promo20 but it came back as expired.
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2009 GSA, 2012 K1600GT, 2008 KLR650, '86 BMW K75C, and always a couple of projects

Offline frankenduck

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Re: Oh CHIT - Lack of Spline Goodness
« Reply #22 on: February 17, 2013, 04:47:27 PM »
Thanks.  I may need to order some parts soon.
Once I had a Collie pup. Dug a hole and covered him up. Now I sit there by the hour. Waiting for a Collie-flower.
New to K bikes? Click here.
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Offline pallum

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Re: Oh CHIT - Lack of Spline Goodness
« Reply #23 on: February 18, 2013, 10:29:50 PM »
M7-1.00 x 25 hex head bolts from Lowes replace the 6 clutch housing bolts. 15k miles and holding.
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Offline frankenduck

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Re: Oh CHIT - Lack of Spline Goodness
« Reply #24 on: February 18, 2013, 10:43:31 PM »
There is a sensor of some kind on the rear of the transmission.  It is round with four wires coming out of it.  Is this the neutral switch?  It appears to be cracked.  However, the neutral light never had a problem coming on nor did I have trouble starting due to it not being in neutral.

Few questions about this sensor (looked it up on Max's - $106.00 - ouch)
1: What does it do?
2: Should I leave it alone or clean it up and fill the crack with RTV?
3: Should it be replaced?
4: Can I jumper the two wires to bypass it if I needed to?

1: Click here:  Gear Position Indicator (GPI)
2: Worth a shot if your gear LCD in the cluster still works properly.
3: If 2 doesn't work.
4: Just pull in the clutch to start the bike. (Provided the clutch switch still works.)
Once I had a Collie pup. Dug a hole and covered him up. Now I sit there by the hour. Waiting for a Collie-flower.
New to K bikes? Click here.
K Bike Maintenance & Mods: Click here.
Buy parts here.

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