R1100GS fork swap & more or my HPF build

[larryboy]

Originally Posted by Fab418

Here's a teaser:

Dude, that yellow thing was gettin' it!! and you were gone!!

[Fab418]

Originally Posted by larryboy

Dude, that yellow thing was gettin' it!! and you were gone!!

The driver of that yellow thing is no beginner either. Pretty decent work in the rough stuff. I was ridding on worn tires and he was on a fresh set of Heidi's. But he did catch up on the smooth stuff; my clutch is badly slipping from a blown gearbox seal.

All in all, this is a serious off road setup. The stiffer springs are in the mail too.

[MotoKaw]

Originally Posted by Fab418

Here's a teaser: ***

More please, and some handling observations?

Bob

[Fab418]

Originally Posted by MotoKaw

More please, and some handling observations?

Bob

The handling is like ridding some big wide enduro bike. If feel that steering lock is somewhat limited compared to what it was and it's a bit annoying when doing a u-turn. But I can slide it around now so it's even. Before the swap, this bike was nearly unridable in thick and rutted sand, now it just blast through with ease. The other amazing thing is how much I can lean the bike when cornering compared to what it would be before. Overall, I feel a zillion times more confident when riding off-road since the conversion.

More vids when I put the .65 springs in.

[Kawidad]

[Fab418]

I got this in the mail a couple of days ago.


Unfortunately, I also have a strange noise coming from the left cylinder and snow is coming soon so I won't be able to try this in a near futur. On the bright side, the build's going to progress more than in summer.

I'm wondering if anyone have an idea about which front master cylinder I could use. I replaced the YZ rotor by this kit from EBC:



I now have a single rotor but a master cylinder from a twin rotor bike which results in a short stroke, hard-to-pull lever. The YZ master and lever won't fit because the lever must clear the turn signal and starter switch assembly. Basically, I would need a master from a single rotor road or DS bike. Any Ideas are welcome. Here's a pic of the master and lever:

[Mr. Canoehead]

I think that the master cylinder off a F650 would work and fit with the BMW switchgear.

Sent from my Droid Tablet using Tapatalk

[Fab418]

Originally Posted by Mr. Canoehead

I think that the master cylinder off a F650 would work and fit with the BMW switchgear.

Thanks! I'll be looking for one.

[gristone]

The welded arms:





All this torque and shear talk and the thing that everyone is missing here is that the 2 stock pieces of tube steel that were used to brace the stock headstock back to the engine (the ones you just reinforced) are extremely susceptible to buckling under load-- especially due to their geometry. This gusseting that you have done with the additional pieces of tube connected back to a wider point on the engine will certainly help, but the thing that would really ensure long term success would be a horizontal tube spanning between the two stock tubing braces at the midspan-- that and making the upper connection between the steel and aluminum a bit more robust. I would bore a hole through the entire aluminum piece underneath where the 10.5mm bolts connect and run a rod straight through and connect it to the new tubing pieces that you put on there.

Anyway, nice job! looks like a blast on dirt-- I have yet to get mine out in the dirt. I have SM wheels on it and it handles beautifully over NY's effed up potholed streets so I can imagine in the dirt it will rip.

[Fab418]

Originally Posted by gristone

..the thing that would really ensure long term success would be a horizontal tube spanning between the two stock tubing braces at the midspan-- that and making the upper connection between the steel and aluminum a bit more robust. I would bore a hole through the entire aluminum piece underneath where the 10.5mm bolts connect and run a rod straight through and connect it to the new tubing pieces that you put on there.

Thanks for the feedback gristone. Theses ideas where discussed and put aside because: the bracing between the top tubes makes them difficult to remove and I was lazy for more complex work that would allow it to disassemble easier for the first part.
The second idea would have been really interesting if it wasn't for the fact that the aluminum part is hollow so you would have to bore a bigger hole than weld-in a thick tube which is rather time consuming and a bit tricky to manage heat and get a proper weld job done.

Right now, I've hammered the thing harder than I ever did with the stock setup so we're going to take everything appart and use penetrating liquid to find any defect in the aluminum part and have a close inspection plus a weighting session to compare it to the stock setup.

Anyway, theses two ideas are on the top of the list should something needs to be done to make this stronger.

Originally Posted by gristone

Anyway, nice job! looks like a blast on dirt-- I have yet to get mine out in the dirt. I have SM wheels on it and it handles beautifully over NY's effed up potholed streets so I can imagine in the dirt it will rip.

Must be a blast when traffic let's you open it!

[Fab418]

No I'm not dead nor the project stopped.

I blew a crank bearing this fall plus a gearbox bearing and I've been busy with other things so the GS sat there for quite a while but summer is here and I'm itching for a ride so...... I got an airhead That I converted (almost done) to cafe racer.

I had to ride something and I always wanted to have something less messy than all the dirt bikes I owned in the past and the GS of course which was never near being a show bike. Not a bad thing IMO.

First ride on the airhead was not very long as I got stuck in 2nd gear after about 10km.... I then learned about the strength, or lack of it, of the shift pawl spring. So before turning my attention to the GS, I had another tranny to do; a 74.

So here's where I'm at:

GS gearbox has new balls in, a new dashboard with dual xenon headlights is near completion and I have a 40k engine waiting on a palet to find a new home. A few pics:

The dashboard and lights:





The current state of the build, airhead in the back:

[RedRaptor22]

I just can't believe you painted that nice aluminium steering head, if anything it should have been shown the proper respect it deserves by applying a fine glossy brush job and some clear coat.

[Fab418]

Originally Posted by RedRaptor22

I just can't believe you painted that nice aluminium steering head, if anything it should have been shown the proper respect it deserves by applying a fine glossy brush job and some clear coat.

I liked it better unpainted too.... Since I want to check it with penetrating fluid, I might as well sandblast it again, who knows..

[Deadly99]

[Whale Rider]

Hey Fab you must have been riding the ass off it to destroy a gearbox and engine still looks good like the dash and headlight change. Her is mine still working on it but good things take time.
WR

Bike1 by boGSer, on Flickr