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New to me 1981 R80GS - restore or leave it?

grahamm

New member
Hello All,

Back in about 1994 I sold my most favorite bike... 1987 R80GSPD. It was a blast! I have posted a picture of it on the site somewhere in the past.

Since that time I have owned a '76 R60/6 then a K100RS and then I found a R100GS bumble bee project about 4 years ago. I restored it and I really like it but for back road exploration I do not find it as nimble as what I remember the R80 to be; I also prefer the simplicity of the single pivot swing arm, the smoother 800cc engine, and overall styling.

A couple of weeks ago I came across a 1981 R80GS, produced in 11/80 serial number 106 - bought it on sight. The bike has been run by a moto collector for the last 6 years as a daily commuter/work horse so it runs great, it is all original but is cosmetically challenged with light surface rust on any black parts and the tank could use a refresh if cosmetics were really critical to value.

looking for opinions...

A) do i ensure the mechanics are all sound then ride it as is....

or

B) restore it with new paint job for frame and tank?

Which will result in a higher value in years to come? clean restore or not restored?

I live in Ontario with 1000's of km of gravel and forest access roads to explore... so I plan to use it with TC80 or more aggressive tires periodically. This bike will not sit in the garage collecting dust. R100GS will get less aggressive tires for longer distances.

Things I will investigate or do immediately:
- desmog?... seems it has a lots of piping that was intend for USA bikes... will look into whether I should remove or leave? New to me as Canadian bikes did not have this stuff typically.
- Speedo.... current is broken, seems common. Will look into restore but in the meantime bought a replica from India for $72 including shipping
- fix oil leak (no crush washer on drain)
- clean and tune carbs
- check the valves and timing
- refresh all fluids...
- Suspension refresh and valving
- Tires and Tubes
and most important - get blue and purple decals for the tank whether I restore it or not:)

Here are the pictures ( I do have good side covers but removed them for the trip on the trailer home):







 
I believe your new mount would benefit from a minor overhaul. Judging by the pictures, there seems to be corrosion or rust on most of the metal parts. To me, that would indicate future wiring issues. The first thing I did with my airheads was lose the epa plumbing. Bombars Beemers in Durham, NC even makes a nice little kit with the correct plugs and even screws and washers for the carb vacuum ports.

If it was mine, I would disassemble to the frame, pull the wiring harness apart and reassemble with dielectric grease. The frame and other metal parts, clean and repaint. I did one frame with POR15 and one powdercoat. The POR15 is indestructable and is the formula that is not affected by sun light.

Don't forget about the valves. They'll need upgrading if the PO didn't do it.

I would upgrade the charging system, perhaps even the ignition. I've used an Enduralast on my GS and an auto alternator on my RS(kind of overkill, but it works). If you're going to ride it, make it reliable. Make it for you, not the next owner. Good luck.
Doug
 
The first thing I did with my airheads was lose the epa plumbing. Bombars Beemers in Durham, NC even makes a nice little kit with the correct plugs and even screws and washers for the carb vacuum ports.

If it was mine, I would disassemble to the frame, pull the wiring harness apart and reassemble with dielectric grease. The frame and other metal parts, clean and repaint. I did one frame with POR15 and one powdercoat. The POR15 is indestructable and is the formula that is not affected by sun light.

Don't forget about the valves. They'll need upgrading if the PO didn't do it.

I would upgrade the charging system, perhaps even the ignition. I've used an Enduralast on my GS and an auto alternator on my RS(kind of overkill, but it works). If you're going to ride it, make it reliable. Make it for you, not the next owner. Good luck.
Doug

All good advise, thanks for the reference to Bombars Beemers.
 
iI f you fully restore it then you might be more concerned about wear and tear to much to enjoy ridding off road. If wanting to enjoy the bike...how about taking care of any major corrosion, and give is a good once over addressing any issues. If you don't know the history of the bike, it might be worth wile go go over a few things. Drop the oil pan, clean out any sludge, check the oil pickup bolts, change all fluids, grease front wheel and steering bearings, grease swing arm bearings, give carbs a good cleaning inside and out. Wouldn't hurt to clean all electrical connections and put dielectric grease on terminals. Check carb and clutch cables, change brake fluid. Address any leaks, ex- pushrod seals, tranny and diff seals. If wanting to paint up the stock tank and side covers, I'd suggest getting a spare beater tank to use off road.

My G/S is very well maintained and parts have been repainted and it looks very nice in street trim ( nice paint on the tank, fenders and side covers), but most of the time I have the HPN plastic tank and Acerbis fender on it, and when I do end up horizontal I'm not concerned about scratching up the tank or valve covers. BTW- I have extra nice valve covers and crash bars in boxes.


most likely if well maintained and enjoyed the value won't be hurt that much...plus you get to enjoy it. If restoring you won't be enjoying it as much for fear if hurting all the nice shinny bits.
 
I'd suggest getting a spare beater tank to use off road.

My G/S is very well maintained and parts have been repainted and it looks very nice in street trim ( nice paint on the tank, fenders and side covers), but most of the time I have the HPN plastic tank and Acerbis fender on it, and when I do end up horizontal I'm not concerned about scratching up the tank or valve covers.

Great idea about the spare tank, looking for one if anyone has a spare...

HPN plastic tank? and Acerbis fender? do you have references for these?

Would love to see a picture of the HPN setup?

Thanks
 
For the Acerbis fender just about any for a bike with a 21" front wheel will do. I think I sourced one from like a Honda 450CR...just poke around on eby and get one. The HPN/Acerbis tanks are hard to come by used and kind of pricey new...like $1,100 or $1,300 used for around $6-700 USD. The bike has a few mods from stock, most noticeable the R100GS front end with HH Race tech cartridge inserts and 4 pot caliper.

Street trim above pict....I have the Standard saddle bags, Happy Trails Bags (for pavement) and Wolfman Expedition bags for dirt....

IMG_0674.jpgIMG_0060small.jpg

IMG_0017smaller.jpg
 
Cool...

R100GS front end? Was it just a swap over or was there lots of a adaptation to do?

How does your setup work off road, does it track well in aggressive stuff or are you limited to back roads without doing much to the rear end?

Reading up on the HPN mods improving the front also needs frame strengthened, more travel in the rear by extending the drive shaft and adaption of the subframe:banghead

I was toying last night, reading all the HPN stuff, of putting a set of 50mm WP forks with custom triple.... then realized how much more would have to be done to make this really perform off road... is this just trying to make it a KTM950!

arg, now this is got me thinking... back to reality to original or all in do what it takes to make this thing go where a KTM can go (I like the simplicity and smooth R80 engine over the modern stuff that is buried under so much plastic) - oh... so much to explore.... front forks, triple clamp, front fender, KTM front wheel and brakes, drive shaft extended, rear shock, rear sub-frame, battery and tray, rear fender, lighting, seat, exhaust...... frame strengthened- yikes, all sounds like fun!

here is a cool company that has done lots of conversions... www.moorespeed.co.uk/bmw-r100gs

Anyone else have good resources on cool R80GS conversions.
 
the R100GS front bolts right up. Just a couple of minor things, the G/S lower headlight bracket is shorter than the GS so either make one or buy one. Turn signal mounts are different on the latter R100GS's, not an issue for the early ones with just the headlight pod like on the G/S. Front wheel is the tubeless onthe GS so if that matters to you, it's a little costly to change the rim to a tube rim...

It's no KTM fork, but adequate for the roads I ride on, gravel, fire roads and such. The rear suspension is fine, but it ain't not MX bike. The inserts were a huge improvement, but that will add $800 to the forks..if you can get them. It would probably be cheaper to do the WP 50 forks, but be prepared to spend some bucks on getting it set up right. Valving and springs.....

Biggest improvement for me was getting rid of the wobbles of the G/S front end...mine was downright dangerous. Many don't complain to much about it, but the wiggle on mine was terible, especially with camp gear. The GS front got rid of all the wobbles, never been an issue since switching.

If I really want to play off road I'll choose my other bike a DRZ400 which is also a wee bit heavy...

If you really want to lear stuff about he G/S look around on ADV rider under oldschool airheads..more info over there
 
Ride it like you stole it, and fix it when it breaks.

I like that thought... one thing I have realized... it handles terrible! The engine and mechanical are awesome... the Steering and Suspension are the Worse. First thing I have to do is figure out is how far I go with suspension upgrades... as it is it would definitely end badly for the areas I like to go. Doing the research now on ADVRIDER and have emailed reputable shop to get advice of the options.
 
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