So, the safe thing to do was to buy wheels with good spokes. Some good luck here - I managed to pick up a front and a rear for $100 each. The rear was great - stainless spokes. The front was "ok" but this is when I find out about the nuances of BMW bike restoration. I had bought a normal R90 front wheel - that's the one with a 17mm axle and I really needed the rare front wheel with a 14mm axle. Bugger!
Its now I realize I need to do better research. There are 6 really great web sites worth checking out:
these sites sell parts and have online microfiches which let you see each component and also where and how it bolts together.
the first is MAX motorcycle parts
www.maxbmwmotorcycles.com/fiche/DiagramsMain.aspx?vid=51889&rnd=03252011
and the other is Capital Cycle
http://secure.capitalcycle.com/BMW-Airheads-1970-to-1995/departments/76/
Two other sites are written by cranky retired BMW mechanics and are absolutely invaluable.
the first is Duane Ausherman
http://w6rec.com/duane/bmw/index.htm
and the other is Bob Fleischer
http://bmwmotorcycletech.info/technical-articles-list.htm
Then there are 2 motorcycle clubs devoted to my kine bike
The airheads club - http://www.airheads.org/
and the IBMWR - ibmwr.org
So, back to the title of this post - stiction. WTF is stiction??? Well, stiction is when things go terribly wrong at the front of the bike.
OK - remember when you got that first bicycle? Every little bump and imperfection in the road would be transferred to the rider. That was before shock absorbers. Now, motorcycles have shock absorbers in the front and the rear. The front ones also hold the front rolling-bits (the wheel). they consist of an upper steel tube that fits into a lower aluminum tube and with springs and such, they take out all those bumps from the road and ensure the bike travels in a straight line.
Now - imagine that the forks are not parallel - what would happen. Well, if they are closer together at the bottom than at the top, the wheel axle will spread the forks at the bottom giving a knock-kneed appearance. If the forks are wider at the bottom than at the top, then the axle will end up giving the forks a bow-legged appearance. Either way, the top tubes will not go smoothly into the bottom tubes and you will experience a not-so-smooth ride. But, we are talking about an out-of-parallel measurement of 1/10 mm and less.
The other plane is even worse. Looking down from the top - if one fork is more forward than the other, the bike will be out of alignment and will want to go around in circles. This is not good! This will make the rider lean permanently either to the left or the right just to keep going in a straight line. To make matters worse - you will be buying a new tire every few weeks 'cos the tires will scallop and everything will get worse and worse...
So what to do? Well Randy Glass (bless his soul) wrote a dissertation on this very thing. OK - the guy is anal but he has a good point. The front forks need to be aligned really well otherwise the whole bike will ride like shit. Check out his instructions at http://w6rec.com/duane/bmw/fork/title.html. When I checked out my forks and steering head, I discovered (eventually) that my forks were bent - the steel upper sections. BUGGER!
Back to the front wheel I bought... I now had a front wheel with the wrong size axle, and forks that were bent. It made sense to buy another set of forks (going price on Ebay is $300) because the forks for each wheel are different. SHIT - more money... Now some luck, I found a set of the correct forks for $25. WOW - what luck.
So I get the forks, I got the wheel, I put them all together, do the anal measurements as recommended by Randy... and all is good! I have a front wheel, its aligned. and all is good with the world! At least that's the short version...
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