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got the R90 out in the sun

898 really knows how to mess up the next owner...they're going to come on this forum and ask what "898" means on the heads!! :stick
 
Strange, I think they were the best.[/QUOTE]

Yes, you are correrct. They were, was, and are the best. :bow:groovy:brow
 
Very Nice. . .

These choke assemblies are SO cool, aren't they? First time I had one apart, I found it so appealing that BMW would put all these wonderful parts into a choke assembly. . .many "simpler" designs are probably out there - like running a naked cable over a hemisphere, but that wouldn't be The BMW Way, and hurrah.

GREAT job on this repair. The Bavarian Elves would be proud.

Walking Eagle
 
898, that's a substantial ground wire you've got there. I need to install a similar rig on my /5.

What gauge wire is that, if I may ask. AWG #10, perhaps? Heavier?

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Another Old Beauty. . .

Very, very nicely done, 898, and your craftsmanship shows at every step of the process.

Any post-mortem on the weeping cylinder base? From seeing your previous work, I'm certain that you cut NO corners on the job, so this is a mite worrisome. I should add, I wouldn't obsess over a little oil 'patina' at the base and I'm about as "anal" as it comes. To me, it wouldn't be worth it to do it all over again right away, and especially NOT during riding season, but I'm sure others would disagree. Hey, this is why we always carry a rag with us, right?

I have a specific interest, having just received new Siebenrock cylinders/pistons/rebuilt heads for a '78 R100RS (MS) back from Ted Porter, and am about to use the Loctite at the cylinder/engine case interface. . .

Thanks for all the great pictures along the way. Lunacy loves company.

Walking Eagle
 
Decided to slightly raise the tank rear about 2 to 3 mm with faucet washers.

Now you've done it...you've raised the bike's CG! :stick How with the plastic work against the paint? Do you see any problems there?? Or are the washers rubber as well...
 
Note the increased clearance for the amplifier and other various parts. Should help keep the amp in the airflow.

I wouldn't think that will help a great deal, but what the heck, it's easy enough to try. It might be more helpful if it was on the front side, but you've just skooched up the rear a bit. Get back to us in another 20 years...let us know the result of the experiement. :stick
 
This is the first I've seen of this thread and your bike, and I have to say it's a beauty.

I do have a question about the Dell-ortos. If you ridden other airheads, is it a big performance bump between those and the Bings?
 
Outstanding! I really like those aluminum tanks and after your comment about it being a good shop project, I've been turning it over in my mind. It would be so much more satisfying to build it yourself. I couldn't figure out how to mold the inside though. Really interesting in watching your project.

Regards,

Barron
 
I marked off the steel brace and almost started drilling, but it looks so cool I figgered I keep it and get a 90/90 front tire next time. Here's another pic, note my new lawn and garden battery with 365 cranking amps at 32 F. Still have to assemble some of the last items including a ninety degree petcock from Huckys so I can git that darn dipstick out a little easier.

On a good note, the color looks like the old BMW folding lock and might deter some thieves.

RPG
 
ummm ... just wonderin' ... 8n8, when you get done dinkin' around with your gas tank could you know out one of the these for me?

7555015948_84069f5ff1_z.jpg


7555015442_cd33d1cd7f_n.jpg


7555015718_855867bc2e_n.jpg


nice project!
 
I couldn't figure out how to mold the inside though. Really interesting in watching your project.

One approach would be to pull a tooling plaster cast (reinforced with hemp bats) off of the interior of a donor tank; you would have to remove the front and rear cross bars. UltraCal B30 is a suitable low-shrink tooling grade gypsum.

From that you would have a "positive" form to measure from to build a wooden buck, if in fact it might just survive as a one-off forming tool.
 
There's gonna be more than three pieces to this tank.

Who cares?! It's looking pretty damned good to me so far!!

Just remember, you don't have to weld the thing up solid; tack it together as you go. That way you can always break a panel loose if you want to change something. One other piece of equipment to consider is a big enough bucket, or trough, or (?) that you can quench your panels in after to anneal them. Most metals "work harden" as they are formed. To keep forming it deeper, it's necessary to anneal the metal with a torch and quench it.

i.e. (not my work)

0606_stcp_18_z+mgs_custom_bikes_gas_tank+tack_welds.jpg
 
Are you going beef it up and to try and use it as a tool, or are you going to take measurements off of it and build a wooden buck?

If you need plaster in a 50# quantity (for example) you can usually get what you need from a local "pottery supply" guy (check yellow pages). A fifty pound bag is probably around $20-25 range. Cheaper than buying it by the pound.
 
Maybe the whole attempt is a bust, but what the hay

Well, if you're going to bite off a chunk, it might as well be a big one. There's no honor in crashin' with the brakes on. :thumb
 
The alternative to buying a TIG rig is going to a local community college. Take a class... If you can gas weld, you can learn to TIG. The skills are similar. Or, pay a real pro, there are some guys who are just artistic with that stuff. Me, I have a nice setup & can weld steel just fine, but aluminum is still a bit of trouble. It pays to get a bunch of coupons cut & practice. Can't wait to see how this turns out!
 
Wood and Iron

Amazing job, 898, no matter what happens next!

Congratulations for sticking with this project - you do beautiful work. Saaaay - maybe you could just use a Dremel tool, hollow out the internal wood, coat insides with POR 15, paint outside to match the rest of the tin. . .gas her up, and GO! No need to find a competent welder or spend money on expensive aluminum.

Just a thought.

Walking Eagle
 
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