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My 1974 R75/6 story

Dude!

Email me. I think I have the part for you.

PM'ed you on advrider.

You can get the manual impact drivers that are quite inexpensive at most harware stores.

I have one, but there's no way I can get a swing at it in that small area. I can just barely tap it.

:bluduh

Last time, I had a neighbor that I borrowed a small 90 degree electric impact from, and after blasting through some non-hardened bits, I got them out.

Nathan,
I hope you blocked the crank on the other end of the motor before removing the flywheel.

Yep, I used crazydrummerdude's patented broken 2x4" chunk taped to the rotor..

17471_478543620190_576805190_11180708_6320165_n.jpg


..with the front cover replaced, of course.

I also endores the manual impact driver as an essential tool. The heft of the thing is just perfect for nudging stubborn screws on a CV carb top.

Exactly!

What ever turned out with your broken starter from the R90?

I was waiting to tear apart my R75 to try its starter on the R90, then I was going to look into the rebuilt starter, and rebuild it as necessary and send you a check or... well, I was just going to play it by ear.

I am still planning on swapping starters this afternoon, so I'll keep you updated.

Thanks again for showing me tricks throughout the years to bring me to the level of a (semi-)competent airhead mechanic!
 
... reminds me of my Honda days!!!

Exactly! Those were frustrating days. But it teaches the right technique, and feel , to doing this succesfully. It is a bit of an art, especially in a confined space.

Short hammer taps should work - the trick is to make sure the bit stays fully and completely engaged - and to mentally mark where you started. It is very easy to keep beating and strip the head when you have already gotten it loosened. Once they are all loosened, even just a little bit, it is time to switch to an appropriate screwdriver, or use the driver without beating.
 
Last night, I checked out Southland Clutch 's ad in the airmail. Figured they might be the place to send my parts for resurfacing.

Anyone have experience with them?
 
southland

I sent my clutch to Southland, the friction plate and the two steel plates. They machined the two steel plates flat and resurfaced the friction plate. I have not put it back together yet. I just got my new clutch spring in Friday's mail. It is snowing here so I'm not in any hurry to get it back together. The plates look real good. It cost about $12 to ship to Southland and then I think $220 for the labor/repair and return shipping. About two weeks from the time I shipped it out until the time it returned. Seems like the way to go to me.
Steve
1975 R60/6
 
Bugger it.

I mailed my clutch pieces off to Southland tonight. Wish me luck.

I forgot to take the front bolt off the starter before I blocked my crankshaft for rear main seal and oil pump o-ring replacement, and there just ain't no way I'm risking it to take that bolt off. I'll wait until the back end is buttoned back up before I tinker with my R90 starter swap/issues. So, that's on hold... still.
 
Nathan,...
you are my protoge'
Regarding the re-built starter, the only question would be the solenoid. I bought the solenoid from e-bay and it was a perfect fit when I finished the re-build. I can assure you that the "nuts and bolts" and the "inside baseball" of the starter are correct. The solenoid is the only questionable thing. However, it was New In Box when it put it on that starter motor. If it works fine on the bench, it should work in the bike. However, I can send you an un-touched starter if you want to try yet another unit. I have thought this through since you posted originally. The original starter came to be broken for a reason. Earlier in the thread, someone suggested that the casting might be broken for the starter having engaged to a running motor. That would suggest a fault with the starter relay. A starter hitting a running motor would be a violent engagement that could break a casting.

You have enough parts to get to the bottom of this by switching out a piece at a time. If you pursue this one piece at a time, it will reveal itself.
By The Way,... I have acquired 2 parts bikes since we last met. If you find yourself needful, I have things you might need.
 
By The Way,... I have acquired 2 parts bikes since we last met. If you find yourself needful, I have things you might need.

dude, 2 questions ...
Where are you finding these things?

Will you be at Pecatonica this year? I have probably talked with you there previously but still don't know who you are.
 
Hey, drummer...when you want to take a vacation from German engineering and relax yer mind with something that makes sense mechanically, make a Harley yer next restoration!!! LOL

The Bassist
 
For me, what has been rewarding, common sense mechanics, and timely is my restoration of a 79 Troybilt Horse tiller........

Rewarding because in this time of instability in our life style, the machine gives me the advantage of being able to produce more food for my table and freezer.

The use of cast iron and common sense parts, linkages, and parts accessabilty makes this project totally satisfying. For instance, the carb was flooding a bit and running rich. Tore into it. Not ONE rubber part, a real brass float, a couple of jets, and mixture and idle screws.......Common sense

Timely cause the deal that allowed me to acquire this BLESSING FROM HIM is just in time to get my spring soil shaped up.............Just thoughts.......Dennis
 
For me, what has been rewarding, common sense mechanics, and timely is my restoration of a 79 Troybilt Horse tiller........

Rewarding because in this time of instability in our life style, the machine gives me the advantage of being able to produce more food for my table and freezer.

The use of cast iron and common sense parts, linkages, and parts accessabilty makes this project totally satisfying. For instance, the carb was flooding a bit and running rich. Tore into it. Not ONE rubber part, a real brass float, a couple of jets, and mixture and idle screws.......Common sense

Timely cause the deal that allowed me to acquire this BLESSING FROM HIM is just in time to get my spring soil shaped up.............Just thoughts.......Dennis


I couldn't begin to count how many lawn mowers, tillers, and the like I've revived.

..and it seems every spring, I have to tinker with 'em all to get them going again. Carb rebuild and starting fluid..

:laugh

One of these days, I'll remember to drain the gas out of every engine before I park it for a while.
 
Snip...someone suggested that the casting might be broken for the starter having engaged to a running motor. That would suggest a fault with the starter relay. A starter hitting a running motor would be a violent engagement that could break a casting.

If the starter is engaged while the motor is running it WILL break the starter nose. A partial engagement will chew up the flywheel's teeth and usually the starters as well.

So far, I haven't seen this resulting from a bad solenoid (I'm sure it happens.) but from accidentally thumbing the starter, when the bikes running and yes, I've done it myself. My Haynes manual's electrical diagram shows a starter lock-out circuit but I've never seen one on a /6 and if any Airhead needs one, it's that series bike.

Even after owning an R-90 for 20+ years, I find the switches on my bike to be monumentally non-intuitive and the turn signal switch is downright dangerous.

Would it be hard to design and install a starter lockout on our bikes? :dunno I know that I can't do it but someone out there can!
 
dude, 2 questions ...
Where are you finding these things?

Will you be at Pecatonica this year? I have probably talked with you there previously but still don't know who you are.

I will be at Pecatonica this year. Myself and Bill Epply and Randy Boris will hopefully have the same spot as the last few years. I'll be bringing my R27 to offer for sale. Look for that bike and you'll find us.

The 2 parts bikes I have recently picked up came from the Chicago area.
1 floated up on ibmwr. It is an R80/7 that had been taken apart for several years. I usually look at that marketplace page early in the morning before I head off to work. I get the inside on a lot of good deals that way. You have to check every day, otherwise the bargains get taken up pretty fast.

The other was listed on e-bay. Someone had removed the transmission and butchered the driveshaft in the process. The speedo was missing and the motor was siezed. It had been brutalized in other ways as well. I was outbid initially but the seller sent me a second chance offer when the other guy crawfished on finishing the deal. In fact, every bike I've scored on e-bay came about in the exact same way.


Right now I know of 4 airheads sitting dormant within 20 miles of my house. Given enough patience I will probably get my hands on them too. 1 is a super high mileage 900 that was in a barn destroyed by a tornado. 2 are 600's that could easily be saved. The last 1 is owned by a guy that wants me to look it over, but I haven't had a chance to look at it yet so I don't know what it is. He doesn't know what it is either. He is a Harley guy and he inherited the BMW.

I network locally with AMCA members and the Harley guys (almost everyone here) and have become known among the middle- aged crowd as a guy to go to regarding european motorbikes. Not a lot of airhead riders locally. That gives me a tremendous advantage in finding bikes and parts.
 
My situation isn't as bad as yours was, I have no problem starting the bike or while riding other than the headlight seems to dim at stops (gen light never comes on and the headlight comes back on most of the time with a quick rev, but sometimes stays off). The taillight and signals will still work while the headlight is out and if I turn the bike off and turn it back on the headlight will come on. Charged the battery and problem still exists, went through the wiring and everything looks good. Was thinking about upgrading the alternator to an Enduralast or an Omega just for the sake of upgrading but maybe that'll help give it that extra charge at idle/low speeds to keep it lit.

Typically, a headlight that goes dim when idling means a battery going flat. That would be a bad battery or a failed diode board or a bad rotor or voltage regulator. Note: your battery is the "soup bone" of boxer electrics. A marginal battery will induce all kinds of trouble. When your diode board goes bad, the bikes ignition and lights will function on what is now AC (alternating) electrical output, but the battery will die a very slow death. If your bike has enough juice to start without charge maintenance, I would think that your problem is not a slow dis-charge, but related to a handlebar switch or relay. My /5's are hot thru the switches and don't have headlight relays, so I haven't had much experience with those. Unless your battery is known to be good, the battery is where you must start on figuring this out.

This also relates to "mymindsock's" observation about the anti-restart function of the starter relay. When we were talking about the electric start being engaged with the motor running, the analog logic circuit in the starter relay that drops the starter when the motor is running detects the motor running by "reading" the alternator output. When your bike, with its original charging system idles down and the gen light flickers, the starter relay does not recognize that the motor is running and does not dis-able the electric start. I solve this problem by running my bikes at a higher idle than specified. Both of my /5's are retro-fitted with the 280 watt, /6 charging system. This allows me to run an idle speed of around 900RPM with the gen light not glowing. I know that is kind of high, but I've hit the starter button on the tank bag enough times to prefer that condition.
 
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Watch your phraseology, young man!

:ha

Dude!

Email me. I think I have the part for you.

Thanks again!

Best practice is to use new bolts every time on the flywheel to crank fit up.

Done and done.

I have one, but there's no way I can get a swing at it in that small area. I can just barely tap it.

20100310002.jpg


There's just no way I can take a swing here. Maybe if the engine was out..

Ok. So, another few weeks of school passed, but I was able to get back at it tonight. On the way "home" from my other home, I stopped by the local airhead shop and picked up a clutch diaphragm spring and flywheel bolts. Talk about pricey..

:violin

I asked the owner; "So, my R90 oil pump cover bolts were nearly impossible to get out due to the Phillips head bolt (rather than hex-head). What do you suggest to free the R75 ones, working in the confines of that small space?" He suggested heating the area and tapping a drift onto the bolt, and that should break it loose.

So, I got home. I spent about an hour and a half with the heat gun, the impact driver, and the drift, tapping and heating in all sorts of combinations. Eventually I gave up and decided to measure my new diaphragm spring. It was .030 below the minimum. I was quite annoyed and called the shop about 20 times and left a message. The guy called me back and said that it's a "heavy duty", stiffer spring whose minimum tolerance is different than my previous presumably "light duty" spring, if you will. Whether or not he was just bs'ing me, I don't know, but I trudged on exchanging annoyance for suspicion. Of course, now, how do I know the service tolerances for this spring?

After a while my brothers showed up and we decided the best thing to to is just buy a similar small 90 degree impact. Well, heat gun and new impact had... no impact! :heh Some more trying and an impact bit experienced catastrophic failure (it killed itself). So, on to the oxy/acetylene torch, after we changed out torch tips (I'd rather not blow a hole through the block). Another impact bit killed itself. More heat.

20100310004.jpg


FINALLY, all the bolts came out.

20100310008.jpg


Cleaned 'er all up, installed o ring and mymindsok's cover, and... Bob's your uncle, as they say. Cleaned out the rear main seal area, installed new one. Installed flywheel. Installed shiny Southland-resurfaced clutch/friction plate;

20100310009.jpg


...and buttoned it all back up. I made sure it turned over and everything, then I took out the starter. For tomorrow, we dine in hell*--- I mean, we'll take a peek at the R90 starter situation, finally.

*I assume this is from the movie 300, but I don't know. I work on old stuff instead of watch movies.
 
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Wow....

That clutch looks PERFECT! :dance

I'm also glad to hear that you got the pump cover and the ancillary parts.

I hope you get a million miles out of em!
 
This is what i want to read about in the BMW ON , what a great article it would be

props to the drummer :wave
 
Nathan, a note on using the mechanical impact driver. Given the space and orientation of the driver in position, what you want to do is take the biggest ball-peen hammer you have and swing it sideways in the space. Hit the end of the impact driver with the side of the hammer head. It still weighs the same and then you can get a better whack on it because the stroke is shorter. The energy generated is the same but the physical orientation is better. Also, using the side of the hammer head gives you a larger striking surface. I regret not telling you sooner, but it just now occurred to me.
 
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