My first restoration (R90/6) where to start?

[r100rt79]

I wanted to post to seek some guidance on how to approach the "restoration" of my first BMW. ...
The bike is a 1975 R-90/6 w/63k miles ... carbs are leaky monsters

I also have a '75 R90/6 and I'm in Brooklyn Center - may be right around the corner from you. I've got a R90/6 (bought new) and it's still running just fine today.
First thing for you to get is a carb rebuild kit (with the diaphragm as you will need them sooner than latter). Oil flush/change mandatory. Make note of oil colors - everyone will want to know if there was water or metal in the oil.
I've also got a '79 R100RT (also bought new from Karl's) and it's still my main ride.
Picked up a '80 R100RT in Colorado a couple of years ago (and drove it home).
Newest bike was a 1983 Harley Sportster XLH (IronHead) until November 28, 2008 when I picked up a 2005 FJR1300. Overworked RT may be able to get a rest.
Contact me by PM (private message) and I'll give you my number so you can tell me the exact condition of the bike and what you want to use it for - Riding or showing. can also contact me at westbankmc (dot) org where I'm the webmaster

You, of course, will then post all of your good and bad experiences on this site so others will be able to learn from you and maybe me also.
I've lurked here and other places for many years and also have over 60mb of AirHead info stashed in the active sections of my hard drive.

Good luck with your project.

 

[krehmkej]

If you disconnect the negtive battery cable at the transmission, be sure that there isn't some other negative lead attached at the battery. If there is one there, it could cause a ground loop and fry the diode board when you pull the front cover.

 

[khoury]

Wow! thank you for posting a book of knowledge- I'm gonna publish it as a supplement to clymer's and share the proceeds with everyone, starting with crazydrummer! so here it is, my 1975 R09/6:
/Users/aronkhoury/Desktop/r90/6#1.jpg



As of right now I've cleaned and coated the tank and am eagerly awaiting my carb rebuild kit, plug wires, etc. here's where its at:
/Users/aronkhoury/Desktop/IMG_0001.jpg
--if the photos aren't here they've been attached somewhere--

In the meantime I getting my shop in order. I ruled out bringing it into my basement so that leaves me to fight the elements in my garage. even with a kerosene heater it is coooold in there- remember jack london's to 'build a fire'- well I'm writing the modern day version entitled 'to build a beemer.' I think I've got it figure out though- hang tarp walls and create a temporary room that is easier to heat.

but a new question (from the north woods) is: I understand you want your valves 'cold'
when you adjust them, but is 10 degrees too cold. the carbs rebuild will happen in my basement but I'd like to also do valve adjustments, break bleeding etc in the garage. is the metal to brittle, is the warming and cooling of the bike gonna create rust? any guidance would be appreciated.

THANK YOU AGAIN to all the airheads that responded to this post- I'd be in the woods without you.

 

[orbitangel]

Fighting the Elements

...that leaves me to fight the elements in my garage. even with a kerosene heater it is coooold in there.

I think I've got it figured out though- hang tarp walls and create a temporary room that is easier to heat.

I understand you want your valves 'cold' when you adjust them, but is 10 degrees too cold?

Is the metal too brittle, is the warming and cooling of the bike gonna create rust?


THANK YOU AGAIN to all the airheads that responded to this post- I'd be in the woods without you.

Short answer: No, 10 degrees is not too cold. You will be rechecking them in the Spring anyhow, right?
There are several reasons to recheck them fairly often, at least at first.

To begin with, you need the practice, right? The more you do this the easier it will become. Once you are comfortable (and proficient) at that task, you can do it at a very relaxed pace and you will be all done in 15 to 30 minutes, if you take your sweet time. It will be a very satisfying task.

Second, you will find (IF your valvetrain & heads are healthy) that everything - valve lash, that is - is real stable and will generally not require adjusting - only checking.

Is the metal too brittle? Nope - no way! It might be at minus 100 degrees F or lower. You don't have to worry - not even in Minnesota.
Forget about it!

What WILL cause rust and corrosion is CONDENSATION - like when you start with a garage at 10 degrees, then fire up ANY kind of COMBUSTION heater which produces water vapor as a combustion by-product. That cold bike and all your metal tools will condense that water vapor like an iced tea glass in June. Here comes the rust you asked about.

Electric heat(ers) will help a lot here. Watch that $$$meter$$$ spin!
Its either that or take that puppy indoors, where it can stay warm.

Good luck!

 

[308NUT]

THANK YOU AGAIN to all the airheads that responded to this post- I'd be in the woods without you.[/QUOTE]



Can you try posting your pics again, would love to see your bike.



Wade

 

[keelerb]

"What WILL cause rust and corrosion is CONDENSATION - like when you start with a garage at 10 degrees, then fire up ANY kind of COMBUSTION heater which produces water vapor as a combustion by-product. That cold bike and all your metal tools will condense that water vapor like an iced tea glass in June. Here comes the rust you asked about.

"Electric heat(ers) will help a lot here. Watch that $$$meter$$$ spin!
Its either that or take that puppy indoors, where it can stay warm."

Absolutely right on all counts. A somewhat cheaper solution is a dehumidifier. I have one in my garage all winter (snow comes in and melts) and spring (rainy season) and use it whenever I see condensation forming on the garage windows (the first place it seems to form in my garage). Not a complete solution, but I think it helps. - B

 

[Penforhire]

No matter how many photos you take it will never have the right views when you reassemble. Take way more than you think you need. Same deal for organizing parts. Take your time and label EVERYTHING. If the parts will be in pieces for months keep some photos with the parts, sort of a hint.

And as a cautionary tale about how costs can get out of hand, check out my 1973 R75/5 resto blog at www.penforhire.wordpress.com . I have many pages of text and photos intended to help inspire and educate.

Don't ever panic. It doesn't help. Take some deep breaths and keep your focus on one task at a time. If a mechanical idiot like me can do it, YOU can most certainly do it.

 

[crazydrummerdude]

check out my 1973 R75/5 resto blog at www.penforhire.wordpress.com . I have many pages of text and photos intended to help inspire and educate.

I remember finding your blog a long time ago. Good work!

 

[keelerb]

Ditto, Penforhire, your blog is one of the all-time great Airhead resources. I have been through it more times than I care to admit, both for instruction/inspiration, and because your writing skill makes it such an interesting saga. Kudos!

 

[James.A]

full of ourselves

It's not boasting if it's true......

I'd be willing to bet that myself and about 20 other cats on this forum can identify every single nut, bolt, or part of an airhead and tell you where it belongs. You have a great team here at the ready to help you along.

 

[SLASHSIXER]

labeling parts saved my bike

I took my R90/6 apart in 1997 for painting and due to many factors, didn't put it back together for 10 years. But I had a surplus of ziploc bags and tore pieces of paper for labels. When I took everything out from the bins, I had no problems re-assembling the bike. I did take about 12 pictures but still couldn't re-route everything correctly the first time. Penforhire nailed it, take many photos.
http://forums.bmwmoa.org/showpost.php?p=206767&postcount=598
Good luck.

 

[khoury]

I'm impressed

I have to say that part of the reason I bought a beemer is that I sensed a willingness among fellow owners/experts to share their knowledge. what I didn't anticipate is absolute complete answers to seemingly un-mechanical questions such as "can I wrench on my bike when its ten degrees below zero?".

the knowledge here is simply awesome. If I inquired, I'm sure someone could provide a legitimate answer explaining (in detail) how to adjust ones carbs to compensate for the increased gravitational pull of the moon during the recent "perigee". (this is a rhetorical question)

 

[Sanders]

I read this thread with interest. I just bought a running R90/6, but it does need some TLC. So I'm trying to soak up what ever I can on airheads. I too am located in Mn. a little south of you other guys (Hastings). It'd be great if we could knock heads with problems that crop up. I'm no mechanic, I tend to muddle through as none of my friends ride...some of my muddleing tends to be wrong, especially with more technical stuff.
Joined the ABC, waiting on my member #. I could use some advice on repair manuals. Haynes, Clymer, or...?? I used to have a '75 Norton waaaaay back in the early 80's and both seemed sketchy at times. Is one better than the other? Oro should I use both?
Any recomendations would help me decide.

TIA
Sanders

 

[barryg]

I've got 5 airheads. I use them all. Get both. Both have their good and weak areas. Ya need all the help You can get. I also use the original BMW workshop manuals and parts catalogs. I f your getting into the charging system, U need Rick Jones book on Airheads charging systems and the Bing carb book to help U order parts for your carbs and the proper procedure to tune them. Good luck.

 

[Sanders]

Good info!

Thanks Barryg.I kinda/sorta thought I'd get them both, hoping that any mistakes would not be duplicated.
I'll be checking out Rick Jones.
Now about that $2K gasket

 

[Penforhire]

You want both those manuals. There are some gaps I found in one, covered by the other. Most of the time the thicker Clymers manual is better IMO. But then there are some things the Haynes manual just does better, for example the color printed schematic in the Haynes manual is the best I've seen (easiest for me to read).