GS wheels on a Rockster.

[trickytree]

Trying to use just stock parts so if anything needs replacing Its just a bolt on job. Photo below of the front end is using GS fork sliders. As the Ohlins allows for some adjustment to length I've set that at its shortest, this makes the forks about 15mm longer than the stock Rockster set up. Larger tyre diameter adds avout 30mm to the hight of the front end so it's sitting up about 40mm.
Rear is a stock length Ohlins, unfortunately no length adjustment on that so the shorter torque arm gives me an extra 20mm ride hight and the 150 rear tyre adds another 5mm.
Upshot is the front is hight than the rear by about 15mm. I'm going to soften the preload a bit on the front as a cable tie on the front stanchion shows I'm only using half travel despite sag being set as recommended. Fronts a bit harsh so I'll try it as is.
Other option is to try the Rockster sliders with the GS bottom yoke.....that will even things up nicely but I'll have to check mudguard clearance. Might have to stick with the GS lowers for the time being as my Rockster discs are all but worn out where as the discs that came with the front wheel look almost new.
Got to turn up a front wheel spacer tomorrow then I can sit and have a bounce.

[ron prior]

Sounds like it is going well so far ? Looks good, please keep us posted as I have though of doing the same thing with my "Roadster"

[trickytree]

Made up a spacer because I don't need the mechanical speedo drive and bolted the front end together and had a bounce....feels OK, can still touch the ground with both feet although the centre and side stands are now to short.
Got a feeling it's gonna work out fine, rear had already been raised so this balances things out again. Never did get on with the steeper steering head angle although I know the shorter GS torque arm is a common mod for 1100S riders.
Started to clean up the Tokico calipers, pad pins were sized solid so had to drill a 3mm hole in the opposite end and tap them out. Got half the pistons moving but the rest are pretty stiff so tomorrow I'll blow all the pistons out, give everything a proper clean and see what we've got.

[trickytree]

Sounds like it is going well so far ? Looks good, please keep us posted as I have though of doing the same thing with my "Roadster"

Pleased with things so far, think it will be OK.
Potential problem with doing this to a R is that you can't swap the bottom fork clamp out, if your going to use a 19" GS wheel things may get a little tight.

[ron prior]

DUH! I forgot about the wheel size difference ! Still interested in yours though when finished. Nice work....

[ron prior]

Over on the 'Roadster' forum there is a member attempting to fit 'GS' hubs, and lace the proper size rims to them. She hasn't posted in a while though.

[sweatmark]

Thanks for posting your progress. Interesting project. A Rockster owner in US (Idaho) did a similar Rockster/GS hydrib a few years back, with some documentation here on the board.

Rockster brake rebuilds: check with riceburner on this forum (and UK-based) who is an expert.

Would be interested in your evaluation of OE Rockster forks supplemented with GS bottom Telelever bracket, as option to your current full GS forks install. I would like to scrambler-ize my Rockster, and prefer the larger GS front wheel/tire for offroad.

[Hidalgo]

Looking forward to a full length picture of the final bike!

[riceburner]

Thanks for posting your progress. Interesting project. A Rockster owner in US (Idaho) did a similar Rockster/GS hydrib a few years back, with some documentation here on the board.

Rockster brake rebuilds: check with riceburner on this forum (and UK-based) who is an expert.

Would be interested in your evaluation of OE Rockster forks supplemented with GS bottom Telelever bracket, as option to your current full GS forks install. I would like to scrambler-ize my Rockster, and prefer the larger GS front wheel/tire for offroad.

You flatter me sir!

Re the Brakes - after about 10 years struggling to keep more than one pair of Tokicos working reliably, I swapped to a 2nd hand pair of Brembos last year. They've gone through a years' commuting through to mid-december (when I took the bike off the road as I bought a car).

I cleaned the brakes of the winter grime a weekend or two ago and where the Tokicos would have had 3 or 4 weather seals blown and over half of the the pistons sticking badly, the Brembos, by contrast, came up beautifully, with NO blown weather seals AT ALL, and ALL pistons moving freely, and releasing off when the hydraulic pressure is release.

HIGHLY RECOMMENDED UPGRADE!!

For Reference - I spoke to Motorworks (UK BMW breaker) and told them WHY I was buying the Brembos, and what I was intending to do - and they followed up on the fiche-research I'd done* and were able to suggest the correct fitment of a pair of R1150RS callipers (IIRC).
Although it might seem that all the R259 BMW models might have the same fitment specs, it appears they are actually different 'enough', that you can't just easily swap callipers between models - the offsets are slightly different I think (so you could fit callipers from a different model and the calliper body would interfere with the disc if the offset is wrong). This is where talking to someone like Motorworks can be very helpful.

* I thought that since the Rockster fork legs and front wheel are (allegedly) the same as the R1100S, that the callipers from the R1100S would be a straight fitment - apparently not!

If you're sticking R-GS wheels into Rockster forks though - you'd very likely have to take some very exacting measurements!!

[trickytree]

Yeah I'm looking at going brembo as a couple of the tocks dust seals have swollen and dislodged from the groove. Can find the 32mm seals on there own but not the 36mm ones.....which is what I need.

[sweatmark]

...Re the Brakes - after about 10 years struggling to keep more than one pair of Tokicos working reliably, I swapped to a 2nd hand pair of Brembos last year. They've gone through a years' commuting through to mid-december (when I took the bike off the road as I bought a car)...

No flattery. You know the R1150** brakes better than anyone I've seen here or elsewhere. Maintaining a year-round bike exposed to UK winter weather appears to requires either expertise, perseverance, or both... metal appears to melt over there.

[riceburner]

...Re the Brakes - after about 10 years struggling to keep more than one pair of Tokicos working reliably, I swapped to a 2nd hand pair of Brembos last year. They've gone through a years' commuting through to mid-december (when I took the bike off the road as I bought a car)...

No flattery. You know the R1150** brakes better than anyone I've seen here or elsewhere. Maintaining a year-round bike exposed to UK winter weather appears to requires either expertise, perseverance, or both... metal appears to melt over there.

I think it's more that the UK weather exposes the issues with poor design choices. The Brembo calliper has a noticeably smaller gap between the piston and the cylinder, so the weather seals are less likely to be exposed to road-crud, which in turn means they last longer. They may also be made of better stuff (couldn't really comment on that).

Perseverance? more like bloody-mindedness....

[trickytree]

Still plodding on. Brembo calipers came yesterday and seem to fit fine...guesswork really as its a miss mash of parts. Getting more tempted to go with the Rockster/1100S fork sliders and fit the 320 discs. Mocked it up and the mudguard clears fine but the rear mounting point doesn't line up so the 'guard will probably need fettlimg. Think I'll swap the discs over tonight and have another look.

[kirby]

Just out of curiosity, why?

Did you just like the spoked wheels or you want the larger diameter front?

Definitely will be unique and having put more than a few miles on the GS types all over the planet the larger front should be a good thing if your looking for dirt riding.

[trickytree]

Why? Good question Partly I'm a incurable tinkerer and partly to be just a bit different.....I do like a nice set of spoked wheels. Also, all being well I'll be looking for a touring bike for next year, most likely a 1150RT so the Rockster can become more of a play thing, and although I don't want to do any serious off roading I'm certainly not adverse to getting it dirty even with 17" wheels.

Anyhow, tonight I put the 320mm discs onto the GS Front wheel and put the 1100S sliders on. Together with the GS lower fork clamp it sits just about perfect. I'll have to make a bracket for the fender mounting but with Tourances on clearance is fine....might be a bit tight with pukka off road tyres but it's highly unlikely that will ever happen.
I might have to use the GS stanchions as the Rocksters are quite short but otherwise I'll go with this set up. I think it looks much better with the larger discs. I'll wheel her outside at the weekend and take some photos.

[kirby]

It will be interesting to hear your assessment of the handling change with the GS front wheel but not the geometry.

[sweatmark]

FWIW This article describes rationale similar to my interest in set of GS wheels and knobbies (plus the required suspension mods) for Rockster, like OP:

http://www.advpulse.com/adv-bikes/why-i ... r-instead/

The larger front wheel should help in deeper gravel found on moutain forest service roads.

For normal travel, OE wheels and sport touring tires.

[trickytree]

I'll be honest, when I bough my Rockster I was looking for a GS but couldn't find one in my price range. If I had managed to find one I'd most likely be more than happy with it, but the Rockster with the GS bars and footrests pretty much does it all.
Type of riding I do has changed over the years....main roads are out and back roads are used whenever possible....if they've got grass growing down the middle and are covered with gravel all the better....and I don't need a GS for that...Probably don't need a 19" front wheel either, that's more me wanting something a tad different.

Anyhow, the postman so been busy this week bringing me lots of little bits that I didn't realise I would need. To fit GS wheels in place of the alloys I need longer rear wheel bolts and shorter front and rear disc mounting bolts, they all came today. Also got a new pair of top bushes and oil seals for the forks. It's looking like I will be able to use the Rocksters stanchions which is good as there in better condition than the GS ones I've got. I'm still waiting for the front brake hoses, should be here tomorrow but to be honest the weathers so miserable here at the moment I'm in no rush to get the bike finished anyway!

[kirby]

I am beginning to understand.

My fav was the r1100 gs 5 speed with the very low first gear which is VERY useful in the rough stuff ('cause of the weight) much better that the rockster first gear which is pretty high. The 21" front and geometry is well suited to dirt toads and trails but the machine will hold its own on pavement as well.
They are a good value now if you wait till you find a good one (I'm looking) and now will not depreciate much more if any, price being driven by condition.
Good traveling machine, good fuel capacity and is comfortable to stand on the pegs(important to me) even with a 35" inseam.
Crossed the Andes on one from Santiago to Buenos Aires and up the haul road from Fairbanks to Pardhue Bay.

I have ridden the new type scramblers, not for me. GS(older ones) has got them beat hands down at a fraction of the price. The only drawback is that they are UGHLY!

Then a 1150GS. You can maintain either with a good multi meter.

Just my .02c

[trickytree]

Was half intent on getting this finished this weekend, the gloomy weather wasn't giving me much encouragement but the ltr. of fork oil I was certain was in the garage isn't...so that's that sorted. Suppose it would give me the time to repaint the fork sliders and lower clamp Ferro Blue but I was putting that of for a bit of a spruce up next winter. S'pose a flash over with some Hammerite smooth wouldn't go amiss but don't hold your breath.

So, ignoring the disappearing fork oil all the bits I ordered during the week are here. 63mm rear wheel bolts as the alloys use 55mm bolts. I reused the original cones.
I already had a new Grimeca rear disk so that went on with new shorter disc bolts (15.5 as opposed to 20mm long). Even popped a new centre cap in the rear wheel....this is turning into a love in.
Interestingly the Rocksters original wheels came with the thin washers between the disc and wheel so I reused those and fitted the 320mm discs. Bobbins and wave washers were all in good condition, original bolts are too long (25 as opposed to 20mm) so have a new set.
The Tokicos were in pretty bad shape, managed to free up 6 of the pistons but on a couple the dust seal had popped out of the groove jamming the piston.....the seal was so swollen I couldn't manage to get it back in. I managed to find 32mm seals sold seperartly but Sod's law said that I needed 36mm seals and those I couldn't find. So I just bought a used pair of Brembos from a 1150RT...there in great condition and fit perfectly.
I'd already bought a couple of banjos and a three way splitter from Venhills so as I could fit them and accurately measure the hose length I needed. It's then that I decided to ditch the GS fork sliders I took all the measurements with and refit the Rockster/1100S sliders so I ideally need slightly shorter ones To late now, this afternoon will determine whether I've royally dingle up when I come to fit them.

So, a quick photo of how it will look. Anyhow, coffees finished so back out into the garage.....and the heaters broken.