Project Katmandu: GS rebuild

[pete.keys]

So this is the start of my thread on the rebuild of an R100GS.

Loads of enthusiasm - but just starting so lets see how long it lasts!!

First the bad news ... she's a real state as she's been left to stand in the mud & rain for years ...

The bloke "Paul" bought the bike in pretty much this condition 6 years ago. Allegedly from some one that had ridden her to India. Then the good news: she runs! When he initially bought her she didn't but he pulled the barrels, checked the big end and little end float, replaced one barrel and a piston and replaced the valve, guides and springs.

On top of this we have
new sump guard
spare set of panels in red and pretty good condition
very good pair of forks
New seat
and ofcourse that 43ltr HPN tank

So now I'm over the initial shock and its down to business and working out how much its going to cost and how far I go with it.

I'll pick the bike up one night this week.

So for starters: what does it take to build up a bike like this....

What I'm thinking for Katmandu is a bike that is as light as possible (as I'm only 5'7" and 65KG).

I'm thinking something similar but with a large hpn tank and g/s style headlight and fairing. I can't find a picture of a bike just like this at the mo .. but I'll keep looking for inspiration.

I did a spreadsheet wish list of bits to make the bike up and it came to £10k ..

https://spreadsheets.google.com/a/pipandpete.com/ccc?key=t7MDW4RnNRsE0EJJGNOyBRg&hl=en_GB#gid=0

Wow those prices stacked up really fast!! I haven't got anything like that amount of money so where do I go from here ...

So I'll start with a jet wash and a stock take.

Do I try and get the bike ridable before I strip it - or just go straight for the strip?

 

[DrFarkoff]

God Luck with That Mine L'escargot is hanging from my rafters of may garage with teh frame al;l powder coated and wheels blasted and sorted, White power shock, Sito Exhaust and a few other wee bits

All I need is a week to stick it back together


Lien vers l'escargot <--- LINK

 

[JohnnyBoxer]

So for starters: what does it take to build up a bike like this....

What I'm thinking for Katmandu is a bike that is as light as possible (as I'm only 5'7" and 65KG).

I'm thinking something similar but with a large hpn tank and g/s style headlight and fairing. I did a spreadsheet wish list of bits to make the bike up and it came to £10k ..

Wow those prices stacked up really fast!! I haven't got anything like that amount of money so where do I go from here ...

That is my old bike and it was originally like this

I didn't build it........................someone in Belgium did

Cost including original bike was 13000-14000 Euros, all in

Sweet thing..........................but not very rideable on the road...............it was/is very dirt orientated

I find my G650XChallenge....................beats it in so many ways - chassis/power/suspension/brakes/handling/price.....................but not charisma though

 

[pete.keys]

Sweet thing..........................but not very rideable on the road...............it was/is very dirt orientated

I find my G650XChallenge....................beats it in so many ways - chassis/power/suspension/brakes/handling/price.....................but not charisma though

Interesting - why wasn't it ridable? The one thing that has inspired me to build one like this is that my g/s is very ridable - I just want more of it.

If I wanted a new bike I'd probably get one .. I want the charisma . I have loved the look of the HPN bikes for years.

 

[JohnnyBoxer]

Interesting - why wasn't it ridable? The one thing that has inspired me to build one like this is that my g/s is very ridable - I just want more of it.

If I wanted a new bike I'd probably get one .. I want the charisma . I have loved the look of the HPN bikes for years.

The Yamaha WR450 KYB forks were too long and raked, for stability in the dirt......................which made not for a good handling roadbike

 

[pete.keys]

The Yamaha WR450 KYB forks were too long and raked, for stability in the dirt......................which made not for a good handling roadbike

Ok that's useful to know - I don't suppose you'd have any measurements on that so I can ensure I don't go that far extreme

 

[ChasF]

There are a number of threads on the subject of the best set up/geometry for modified airheads in the 'olds cool' section on advrider.

The WR forks could be dropped through the yokes a bit to try to make it a bit more road friendly but it's always going to be a bit unpleasant on the road on those tyres.

 

[JohnnyBoxer]

Ok that's useful to know - I don't suppose you'd have any measurements on that so I can ensure I don't go that far extreme

Ask Wreford Miles.....................he's the current owner of this fabulous bike

 

[Redboots]

After seeing this from Mat Beekers of bmwboxersupplies, I picked up a set of WP Extreme 50's.

Keeps the "look" right, impo of course

John

 

[pete.keys]

After seeing this from Mat Beekers of bmwboxersupplies, I picked up a set of WP Extreme 50's.

Keeps the "look" right, impo of course

John

Very cool looking bike - thats the sort of thing I'd like to build. Forks must have cost a fortune?
If you have the time would you mind measuring and letting me know the dimensions of the forks. 1) Length from centre of spindle to top of fork. 2) Distance between inner sides of the yolks 3) Distance from centre of spindle to top edge of bottom yolk.

Have you altered the rear in any way to compensate for the longer forks?

cheers

-Pete
.

 

[judge]

F650 front end I believe drops right in without spending fortunes on wheels, yokes, forks, brakes and all that fannying - Rob Farmer has recommended this route in the past whether he did it or not I cannot remember - was too busy eating a sausage sandwich at the time

 

[Rob Farmer]

To be honest there's nothing wrong with the standard paralever forks or bike for that matter. The only weak spot is the drive shaft and there is a viable alternative to that now. Keep it simple and do it well would make a lot more sense for a trip. If you only weigh 65kg you don't want to be wrestling with some imposing machine. I sat on garryh's beautiful hpn bike. It was a huge machine that made my 1150 GSA seem small. I wouldn't want to wrestle something like that off road especially with luggage on.

 

[Beemerboff]

Im with Rob on this - I have a Ohlins shock with a 80n spring and the HPN inserts on my GS , and everybody who has ridden it discribes it as the best handling Airhead they have ever ridden, bar none.

It is miles ahead of my G/S, and the PO spent heaps dicking around with one of our local experts, Biketec, trying to improve that .

The paralever system just works better than the mono, particularly when the bike is moving and hitting bumps.

The HPN inserts are NLA. but the main difference seem to be that they had 20 mm less rider sag , a bit less compression damping and a fair bit more rebound than stock and you shouldnt have too much trouble replicating that.

For about five grand less than a trick front end.

Same with the exhaust - every test I have seen seems to find that the stock collector/ system works best, yet most of these photo bikes have some big bucks alternative, again style over substance.

But if you dream of owning a GBP12,000- photo bike dont let a few old farts put you off, just go and live your dream.

 

[mikyh]

Listen to Rob and Beemerboff -

They are absolutely right
Miky

 

[AliBaba]

I have two bikes:

1) Kalahari with Øhlins and inserts, mileage since 2006: 28km
2) Basic rebuild to HPN-Rallyesport, , mileage since 2006: 60.000km

Yes, the Kalahari works excellent but it's more fun to ride a "special". If you think you can handle a rebuild then go for it!

 

[pete.keys]

USD conversion - do I don't I?

USD conversion

so far 1.5 for and 2.5 against.

For the past few months I have been working on some options. I don't want to go the full Kayaba/WP route as I concur that they may be too aggressive for my needs

I have read threads on upgrading G/S forks to GS. On upgrading GS forks to say DR650 or GS650 forks and the like.

Key considerations are the ease and cost of the conversion.

If I keep the GS forks then I definitely need to upgrade the brake. My G/S was a death trap with the standard brake even though everything was new (disk/pads/hoses). I upgraded it to a 6 pot billet calliper on the std disk and now the brakes are actually excellent.

The Kayaba forks are 960mm long as opposed to the GS forks which are 775mm (actually G/S not measured GS yet). The distance from the lower head stock to the centre spindle on the GS is 600. On the Kayaber its about 740 (needs verifying) so raises the bike 140mm at the front - a whopping 5 1/2 inches in old speak.

Next consideration is the headstock length. The G/S is 180mm. One of the issues on the DR650 conversion is that the headstock is much longer so it needs meddling with the tripple clamp stem.

Next consideration - bearing sizes. GS is 28X52X16 - so Ideally need forks with bearing height and max diameter the same.

I have been looking for a compromise and an easy swap and think I might have found one: I managed to acquire a set of nearly new DRZ400 SM forks for £106 including yolks. They are made by Showa and should be pretty good?

Length 910mm. Distance from top of bottom triple clamp to centre of wheel spindle is 660mm so only 60mm or 2.3" longer than std. Bearing size 30x52x16 so that fits - and the headstock length appears to be 180mm as well!!

I reckon the wheel, 310mm rotor and calliper will set me back another £250.

Thoughts ....

Do I still keep it simple? perhaps I should get the bike ridable and try it as standard.

It would be useful to test ride some examples - any offers?

 

[Rob Farmer]

More braking than I'll ever need cost £41 and a bit of time with a hacksaw and drill. Works with the original brake line and means I can get brake pads straight from BMW with the rest of the parts I order.

4 pot 1150 caliper off ebay and a piece of Dural

I've since scrapped the cast disc. It warps as it gets hot. An original stainless disc works much better.

I'll be powder coating the bracket this winter.

Not trying to put you of modding your bike Pete but if you're doing a journey and anything brakes you may need to get bits off the shelf to repair your bike. If you have custom parts you're going to be stuffed.

 

[Steptoe]

The other type of BMW badged caliper gives you a deeper swept pad area.

That type of caliper has a long shallow pad and the disc is deep, if you know what i mean.

 

[AliBaba]

It might require some work with valves, oil and springs to get a SM-fork to fit.

Have you checked that there is room for the wheel when the fork is fully compressed? How much suspension-travel do you get?

I reckon the wheel, 310mm rotor and calliper will set me back another £250.

It might be possible to adapt the wheel you have.

perhaps I should get the bike ridable and try it as standard.

It might be a good idea.

 

[Rob Farmer]

The other type of BMW badged caliper gives you a deeper swept pad area.

That type of caliper has a long shallow pad and the disc is deep, if you know what i mean.

Yep.

But it was cheap and works a treat.