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Suggestions on how to Lighten an R850R

senseamidmadness

Neglected Bike Adopter
I'm thinking about putting my R850R on a diet. Nothing too extreme, but I'd like to shave some weight where I can.

What would you folks suggest for ways to drop a few pounds that won't harm the functionality of the machine?
 
Exhaust

I have an R1100R and didn't realize how heavy the stock exhaust is. Years later the catalytic converter started clogging and I needed a new exhaust. Seeing the price of a new stock one I explored and found a GPR Trioval on the big auction website. The stock exhaust is somewhere around 40-45 pounds give or take, the GPR probably less than 5. It definitely revs more easily above 4,000 rpms all the way to red line too.
 
I have an R1100R and didn't realize how heavy the stock exhaust is. Years later the catalytic converter started clogging and I needed a new exhaust. Seeing the price of a new stock one I explored and found a GPR Trioval on the big auction website. The stock exhaust is somewhere around 40-45 pounds give or take, the GPR probably less than 5. It definitely revs more easily above 4,000 rpms all the way to red line too.

How do you like the sound?
 
Take everything off it except what is needed for it to run. Make it a cafe racer. Cut down the bars and just use one small bar end mirror. Convert it to a single front disc brake and pitch the entire abs unit. Passenger foot pegs, rear rack, passenger seat, speedo, fenders…take ‘em off. Get rid of the air box and tape the air temp sensor to the bottom of your seat and put stainless screen over the throttle body intakes. Do the exhaust thing mentioned above. Drill out the foot plates with a zillion holes. Never put more than 2 gallons of fuel in it. Ultralight wheels and smaller tires would not hurt either. Easier to spin up the rotational mass. Tell us how it goes :)
 
How do you like the sound?

It is noisier than the stock exhaust without a doubt but not egregiously so. When I am engine breaking I occasionally hear a pop that the cat on the stock exhaust got rid of, but overall I don't mind it. I would prefer it a little quieter, but not enough to add the extra weight of going back to the stock exhaust and I'm used to the change now. Earplugs pretty much make it a none issue.
 
Do you have to do anything other then reset the Motronic?

I will add this to my winter project list.
 
I did a AF-Xied O2 manipulator (https://www.beemerboneyard.com/bmwafxied1100u.html) years before the exhaust but only at its lowest setting. Honestly I think a really good throttle sync solved the problem more than the AF-Xied did and at higher settings the bike became very thirsty. That said, I did just order a chip from John Gemi. No injector upgrade, but when I had them cleaned a few years ago one side was so clogged it did little more than dribble fuel.

I'd say just go incrementally with what you think you need. Dropping weight will help, cleaning the fuel injectors never hurts. If you think your running too lean (not sure how to tell other than maybe surging), then the AF-Xied. These bikes really just purr when well maintained with a good sync. Yes, newer bikes do it all faster, but even my twenty year old bike is still more capable than I am.
 
I scrambled an 850R a while back

Get rid of the stock exhaust
swap the entire instrument cluster, headlight and brackets for light weight aftermarket stuff.
Find a GS top triple clamp and install some modern conventional (aluminum) handle bars
If you don't carry passengers dump the rear seat and passenger pegs
If you figure out and fabricate brackets and piping swap out the stock dual oil coolers for a single after market right below the headlight
If its non ABS and your handy with electrical stuff get rid of all the switch gear and brake & clutch lever stuff and install some light weight aftermarket levers and throttle control
Remove the stock airbox and either use pod filters
Use a smaller lightweight high power battery and if your handy with fabrication swap out the ten pound battery box made for the smaller battery
Dump the center stand and just use the side stand
Tail light assembly and rear fender can be swapped out for something a little smaller and lighter

I will be digging out my Scrambled 850 sometime soon in order to take another swing at getting it slimmed down and the above list is what I have in mind. I've already swapped out the exhaust, headlight and added some GS stuff but I think I'm just going to strip it down a little more.
 
Mildly related -- I've seen pictures here and there of a lightened/skeletonized Paralever arm, but upon web searching can't find anything more about it. Was it an aftermarket part offered by somebody, and was it just for the S?
 
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