Hi all, Just got my 1989 100GS and about to start prepping it for RTW trip.
Please can anybody guide me as to what mods i need to make, what parts i must re-new before i leave. It has been looked after but done 50k miles.

This is just a list of things that i know i need help with,

Change the standard handle bars to narrower 790ish possibly Renthal, can i keep the BMW switch gear! Can i fit oxford heated grips!

Uprate the front brake, what calliper do i need etc!

Do i need to get the whole bike re-wired or just the charging system!

My bikes only got a nose fairing with no screen, can i get an after market set up like on the Dakar!

What parts should i take on the trip.

All advise would be helpfull.

Please feel free to email me at twowheels03@msn.com

Thanks Paul

You can start with this link:

http://www.horizonsunlimited.com/hub...long-tour-7818


There are a lot of different opinions on this one. Personally I don’t think another caliper is worth the cost, consider overhauling the old one (and the masterpump). If you want better brakes go for a setup with bigger (or dual) disk.

If the wiring is okay it’s not necessary to modify it but make sure that all cables concerning charging is okay and the contacts are clean. Change brushes (if necessary) and it might be smart to carry an extra rotor.

I have no idea… Why narrower?


It’s possible but you will need various parts and a PD-tank, it will add a lot of weight. Personally I would have used HPN’s fairing and tank.

It depends on your route…
Airfilter(s)
Oilfilter(s)
Spark plug
Tubes
Clutch wire
Throttle wire(s)
Brake lever
Clutch lever
Rotor
Silicon
Tape
Electrical wires
Fuses

It’s possible to store most of the items inside the frame (under the tank) and attach the wires to the bike.

Considering the milage and hoving no idea what kind of maintinence the previous owner preformed, i would seriously consider having the driveshaft replaced with a re-built one with greasable u-joints. Mines got about 100k. miles on it now. Same with the transmition, maybe it's due for a new set of bearings (do the cir-clip thingy while your at it!) You may consider a lower first gear while the box is open, depends if you plan to get off the beaten path a lot, it really helps maneuver the beast around. Huge amounts if info on the HUBB about brakes, you'll have to search or i'll be repeating myself . If you keep the stock charging system, remove the rubber mounts on the diode board and get solid ones. Definately carry a spare rotor. Same with cables, they're light and easy to pack. Put on some real barkbusters from Acerbis, the ones with the aluminum bar molded into the plastic, it'll save your levers and M.Cylinder. The stock bars are fine, but you can buy kits to install tapered bars...really not necesary though. I had a REALLY hard time finding a comfy set for my bike and actually miss the original bend, it was the most comfy. Make sure your comfortable with the bike before you leave, and you know how to maintain it. get rid of the paper filter and get a UNI FILTER, they're washable. Use soap and water and let it dry. Don't forget to oil it! And remember, the red light on the dash is susposed to come on at idle . See link:
http://web.mac.com/adventman/iWeb/Site/Welcome.html

Thanks loads guys for some good solid info, I will put it to good use.
Regards Paul

After well over 100,000 k's on my 1993 R80GS a few thoughts from my side:

The circlip should be ok. What Mr. Ron is thinking about is that for 8 months in 1993 the circlip was omitted and instead the bearing was additionally glued in. Big crap - mine got unstuck at 18 thou resulting in a major gearbox balls-up. What makes sense is to check the 5 main bearings in the gearbox and replace them if necessary. And while you're at it, exchange the cog for the first gear against a shorter and the 5th against a longer ratio. AND while busy with the gearbox get rid of the standard clutch and replace it with a ceramic. Lasts for the rest of the lifecycle of the bike, even if you really grind it in sand and muck.

Exchange the standard front springs against White Power progressive springs.

Exchange the rear shock against either Oehlins, White Power or Wilbers if it isn't done yet. They can be rebuilt and last muuuuch longer than the standard Beemer shock. And perform much better.

The standard brakes are sufficient for dirt roads, otherwise careful riding... The rear brake can be fitted with softer linings which improves the drum brake considerably. The front disc could be exchanged against 320mm discs from HE (Supermoto Supermotard Funbikes Monobikes Felgen-einspeichen Speichenraeder Bremsscheiben HE-Motorradtechnik Freilassing Motorradfelgen) unfortunately only in German. But I found them to be adequate.

I rather like the standard handlebars, but lifted them by 2.5cm. Try Touratech.

Personally I'd stick to the fairings you've got. The newer fairings with the higher windscreen produces more turbulence around the helmet causing more noise. I finally sawed off my screen so it's even shorter than the older fairing.

I fitted the Acerbis/HPN tank and wouldn't like to miss it. Check the web - there are always second hands for sale.

Check the driveshaft, but if there is no play, just carry on. I've still got my first and it is still good. Mind you, I don't try to dice anybody, but I did lots of dirtroads.

Take a rotor along and don't forget the special screw to remove it. Take a spare diode board and regulator along.

My two-pence worth.
Hans

__________________
Only when we pause to wonder
do we go beyond the limits of our little lives.
(Rod McKuen)

Sorry, what I forgot to mention. Second thoughts ;-)

Scrap the standard bashplate and take a Dakar plate. The standard palte was probably more for decoration porposes and cannot take any beating.

Get rid of the pannier rack ant get a Touratech or try your own creation. The standard rack is too weak for bad roads whith luggage.

If you intend to cross many a deep river, think about HPN fittings for the breather of final drive and gearbox. The HPN goodies are fitted with a tube going into the airbox, so no water can dilute the oil.

Depending on how tall you are you might think of lower footpegs. Try Touratech. Additionally you could redo your seat to raise your seating position. Makes sense for people over 180cm.

I fitted a second sparkplug per cylinder, but that isn't really necessary. The engine runs smoother, but what I found much more important was to balance conrods & pistons. This made a hell of a difference.

That should do.

__________________
Only when we pause to wonder
do we go beyond the limits of our little lives.
(Rod McKuen)

I'm quite sure the circlip is missing on the output shaft on your bike. I had one installed on my '89 - the circlip groove had to be cut. While you are in there, the lower first gear is a good idea. You HAVE to get this done if it is not already. Catastrophic failure if you don't.

For bashplates, the Touratech one is a bit bigger and stronger than the Dakar.

Check out Motorrad Elektrik - #1 Source for your BMW Motorcycle Electrical Needs for over a Decade! (256)442-8886 Rick is a sponsor of this site and everything he sells is good stuff. I got a high output voltage regulator and a Panasonic gel battery from him four years ago, rode around the world and the same battery is still in there and working great.

There is lots of info. on your brake options in the BMW tech section. I think Motobins will sell you a K-100 calper and mounting bracket that is supposed to work well.

Upgrade the diode board and mounts and carry a spare (I hard mounted a Thunderchild diode board and it still burned out on me- alone in the desert in Sudan but I had the stock one as a spare)

I agree about the shocks. Front and rear have to go.

If ceramic clutches were any good OEM's would have started installing them a long time ago.
Some interesting info about the origin of the ceramic clutch sold by Touratech.
These clutches are made in South Africa and although I have not been able to find the manufacturer direct I know that similar clutches made for car models sells for around 75$ US. The price from Touratech is around 560.80$ US.
I personally know the supplier or the company that used to supply Touratech and he has a reputation for asking the most incredible prices for any work or parts from his workshop. Now wonder the extremely inflated price by the time it is sold by Touratech.

The worst is that this clutch offer no advantage over the standard clutch fitted to your BMW model.
For a clutch to withstand tough conditions for longer it must have an enlarged friction area, this will prevent the clutch from slipping under heavy load like driving in thick sand with off-road tires.
The ceramic clutch offer far less friction area so will be more prone to slippage.
So what if you can't destroyed the ceramic clutch when it start slipping, all it will do is start to destroy the more expensive parts of the clutch like the clutch spring plate and the housing cover.
If you want to improve the clutch you can get the racing clutch from HPN, this will mean you will have to replace all the clutch components but will still cost less than buying the ceramic clutch for which they recommend that you replace the other components of the clutch for better relayability an any case.
By the way the clutch supplied by HPN has been proven in the Paris to Dakar rally many times over.

You will receive a lot off advice and I am sure a lot of it will be very conflicting.
The most important thing is to keep it as simple as possible and as close as possible to the standard as you can. This is the whole reason for using the bike you have. They are simple and easy enough to be maintained and repaired in the most basic workshop and you will find dealers all over the world that can supply parts. The more you change and modify the less dealer parts will be available to help you should you run into trouble on the road.
I admit thought that there are a number of weak areas that need some attention.

BRAKES - In the front you can fit a cast steel disc the same size as the one on the bike but it has more friction and the one supplied by HPN is mounted floating also improving the braking.
In the rear I will fit a floating cam with upside mounted lever. From HPN this comes with new set of brake shoes (you cannot fit the factory part here afterward but you can keep your old cam handy if you should run into trouble. The floating cam ensure that even pressure is applied to both shoes even when they are unevenly worn. Fitting the upside lever cost the same as the one pointing down it is just more out of harms way.
These changes will not turn your brakes into dead stoppers, but will improve braking and make your brakes more reliable. When on dirt they are more than adequate and even for highway riding if you stick to safe speed limits.

PANNIER frame - The frame mounted to your bike is the best there is if it is still the original BMW factory frame. They have a tendency to crack where the bottom tube is attached to the frame. This is easily rectified by adding a small gusset between the two tubes. I can shoot some pics to show you what it should look like.

GEARBOX - The Gearbox is a problem area but can be sorted if done correctly the first time. BMW have a special bearing but it has to be installed with the infamous cir-clip to be effective. The shaft on your bike where this bearing fit might not have a groove for this cir-clip as some clever engineer decided it was not necessary to install these for a number of years up to 1996 that is.
Gear ratio changes make small differences and I would not put to much emphases on these but if you have to box open in any case, they are not to expensive and will have advantages like better torque when driving really slow or better fuel economy when cruising in fifth.

BASH PLATE - HPN supply a deeper sump that come with a very thick bottom plate that act as a bash plate as well. This sump will increase your oil capacity making the interim for oil changes longer. Together with this I will also add a oil cooler if one is not already fitted, and with this you can also consider the HPN thermostat. a Thermostat was fitted to al the 100's except the GS and this help with warming the engine more rapidly as a cold running motor has more wear than one running at operating temperature. (Sump, cooler, thermostat are all components to increase engine life.)

FUEL TANK - The HPN 43 litre tank is fabulous as it keep centre of gravity low where you want it and allow for the most comfortable seating position even for very tall riders. This tank also offer additional mounting points spreading the distribution of weight, something that the larger BMW tank do not do.
To fit this tank you will need to have a oil cooler relocation kit as well.

FAIRING - HPN offer the adventure fairing which come supplied with headlamp and mounting gear to fit to the triple clamp of the WP forks they fit to the modified frames. You will have to check though if it will fit the Marzocchi forks on your bike. This fairing integrate nicely with the HPN tank.
You will also have to order a dashboard or make your own.

SUSPENSION - The Marzocchi forks are great but the BMW rear sock sucks. Here I would definitely fit either Ohlins or White Power.

This list can go on and on but you can also look at this site hpn

Re ceramic clutch - it could be that TT has different suppliers in different countries, which doesn't sound good because it could mean that you get different quality although all under the brand of TT :-(

I fitted a ceramic clutch from Sachs, Schweinfurth, sold under the title "Sports clutch". After I wrecked my first (standard) clutchplate in difficult terrain at only 18,000 k's I fitted this Sachs product (90,000 k's ago). I strained the clutch heavily in Oz, riding sand and letting the clutch slip. No probs up to now. Besides that, once you get oil on the standard clutch it is rendered iseless. The ceramic only needs to be cleaned properly to be in working condition again.

None the less, it always depends on how much you are prepared to spend on changes. Many are "nice to have", but not really necessary, others are important. Checking the circlip e.g. According to the Clymer manual the circlip was only omitted in the first 8 months of 1993, but I'm no specialist and as others have mentioned before, this should be checked.

__________________
Only when we pause to wonder
do we go beyond the limits of our little lives.
(Rod McKuen)

As far as the circlip issue goes, there is a lot of diferent opinions. lots of info here:
http://www.advrider.com/forums/showt...hlight=circlip
http://www.horizonsunlimited.com/hub...ntribute-24620
My own personal feeling is the circlip doesnot absolutely solve the problem, and not all non'clipped transmitions are destined to pre-mature failure. Mine is proof of that, along with many others. i've seen circlipped transmitions develop the same problems than non. Mine doesn't have the circlip and does quite well without. Truthfully, for peace of mind, the next time i open up the box, i'll get it done and see if there is a difference afterall, but i'm not convinced..
My theory is it's the shaft itself not machined to proper tolerance, resulting in a lighter interference fit. It's also a bad choice of bearings from BMW, the rear should be a thrust bearing, like is found in most other transmitions. Anyways, we're getting off topic. If you do decide to open the box, it wouldn't hurt to get the circlip installed when you put in new bearings.
There's been little talk about the driveshaft issues on the bike. Like the transmition, results vary. I strongly advise you properly inspect the driveshaft and lube it properly with Moly based grease, like Optimol or another product from Honda (sorry, can't remember the detail.) If the driveshaft does need replacing, for the price of a stock, you can get a greasable one from here
http://www.brunos.us/Gearbox%20Transmissions.htm
...oh, one more thing. If the transmition gets opened and the rear seal replaced, make sure that the breather hole on top of the seal-housing is sealed with silicone. This is often missed, even by experienced Airhead mechanics and is particular to the airhead GS only. Make sure all the rubber boots are in good condition, replace if necesary.......


...okay, i'm done for now

Guy's, can't thank you all enough for the help you have given.

I will do the gearbox stuff ie, circlip and 1st and 5th ratio's.
Also the Diode and rotor.
Also thinking about the HPN tank, any thoughts on the best place to look for 2nd hand!
The greasable drive shaft i think is a must and replace all the bearings etc.
What do you think about the standard switch gear, should it last with 57k miles under it's belt!

Thanks again

Paul

You should have no problem at all. It's quite serviceable and can be cleaned. I just use WD-40 for mine. Your bike has very low mileage, most of the parts should be in very good condition as long as it wasn't abused. Be sure to adjust the valves regularly, they tend do regress into the seat after about75k-100k Km. Way down the road, if you rebuild the heads, replace the lifters and the rings. NEVER let someone hone the barrels! They will outlast the rest of the bike. (small cost there) Have fun and get to know your bike intimately! It's an awesome machine and if properly taken care of won't let you down.

Circlip was not fitted between models from 1984/85 right up to 1996 after production stopped. The only new models to have them will be the Basic and Kalahari.

Honing is essential, the roughness aid the ring to bed in and develop a flat profile with the cylinder wall. If you do not hone, this important part of the running in process will not happen and as soon as you start hammering the bike after the initial run in period the rings will heat up too much and this causes them to develop a dish shape making even less contact with the cylinder wall. The end result is a smoky engine with higher than normal oil consumption.
Honing the Nikasil cylinder can be a problem, as to much aggressive honing will eventually strip of the nikasil coating of the Aluminium.
- For you that don't know; in 1980 BMW started making the cylinders completely from aluminium and coating it with a very thin but very tough nikasil coating. This gave the cylinder walls incredibly long life at the expense of the piston rings. Rings are less expensive to replace so this is a welcome change and it does increase engine life overall -.
Honing should be done by an engineer that does nikasil cylinders in general and understand the danger.
Normally a honing tool is used that look similar to a bottle brush as this type of honing device place very little pressure on the walls but still enough to leave the hone marks in the tough nikasil cylinder wall.
The purpose of honing is 1st; to aid the shaping of the rings during run in period and 2nd; oil get trapped in the grooves providing adequate lubrication to the piston rings. This is why nicasil engines last longer because the grooves does not get worn away providing less lubrication with age.
Even though the grooves is still in place after many miles, the walls are to smooth to bed the rings in properly, so it is for this reason that a light hone must be done.

Thanks Ron, I will keep the stock switch gear.

As I know very little about engines apart from maintaining them I'm getting a Guy who works for BMW Park Lane in London to look at it for me. If he thinks the pots are ok I will leave well alone but I guess that if worn i will have to either get them honed or get new Pots.

If you have any more advise no matter how basic it is to you, it might be very new to me so I would be greatfull if you can think of anything.

Thanks to the GS Workshop also.

Regards Paul