The BMW GS boxer twin thread

[Padmei]

Hi guys, while we were away I saw a post on a thread, maybe ADV rider, showing a shortened torque arm on an Airhead GS.
I can't find it
Does anyone know where it is. ?

Cheers

if it's just one with a pic of it & no info I recall seeing one this past week. I believe it was from a link to a german or dutch site. Sorry I can't be of more help

[Box'a'bits]

Hi guys, while we were away I saw a post on a thread, maybe ADV rider, showing a shortened torque arm on an Airhead GS. I can't find it Does anyone know where it is. ? Cheers

I talked to Redboots about it, as an off topic excursion in one of the Unholy threads . Here's the page for the thread on that.

Prutser talked about it for one of his old Paralevers. He also looked at an 18" rim for the Paralever (small increments to gain ride height). Finally, the other thing I thought you might find interesting in that thread was the work he did on DRZ forks.

Re the shortened torque arms, it's an area I'd like to explore

If you do decide to go down this track please let me know.

[Phreaky Phil]

Thanks for that, i really like the look of that bike. Almost a favourite
I might do some investigating into the angles of the rear drive and what happens to things with a shorter arm.
The shock would have to be lengthened as well.
I wonder what the rear guard he has is off ?

[GSers]

Same angels as they have on the R900RR the rear final drive and the paralever are almost in a straight line.
I moved the front mount about 15mm forward on my build saved making a custom bottom arm.
The final drive moves down as the swingarm moves up.
Watch for U-joint binding nothing a dremel wont fix.

GSers

[Box'a'bits]

The shock would have to be lengthened as well.

I don't think that is necessary

I wonder what the rear guard he has is off ?

That's off a KTM. Same (taillight etc) as what I used to have on the 640a. The tail light on that was a bit marginal. Taz put an led strip under the tail to brighten things up.

[Phreaky Phil]

I don't think that is necessary

Are you sure about that, surely if you shorten the torque arm the shock would have to be longer as the final drive is pivoting around the paralever. ?
in the attached pic you can see that it has had the shock postion changed, i figured because of the shortened arm.
and it would make the shock be on not as steeper angle.
I guess i'll find out when I whip the shock out and start playing.

[Box'a'bits]

No I'm not sure about the shock length. I was basing this on the conversation with Redboots. Maybe a good time to question him again now he has the thing up & running. I don't think he elevated it too much - he could still use the centrestand, albeit that the wheels weren't off the ground.

A further (separate) mod seems to be to relocate the shock mount on the frame, in order to gain height from the shock sitting more vertically. Your photo show this. My concern there would be the additional stress this introduces further away from the main frame. I'm guessing with is the reason for the brace dropping down off the shock mount.

I've sent him a PM over on the other forum, & CC'd you into that.

[Phreaky Phil]

Is the white and blue bike in you pics, Redboots bike ? Do yu have any other info on that bike.
It looks like it has an 18inch rear wheel.
How do you find the handling/steering on your bike with the USD forks clamps, compared with the original clamps with the greater offset ?
Im not sure what way I would like to go if I do another mod on the GS, use the smaller offset clamps and do something with the tank to get some turning clearance or get some of the HPM guy clamps. Hmmm.?
I feel a project coming on ! !

[Kokopelli]

The driveshaft on this bike has quite a steep angle. My understanding was that they used a short shock on the R80GS Basic to make the assembly more durable. I guess if you want performance and you are prepared to repair or replace components, it doesn't really matter. The Basic always looks like it's squatting, I can't say I like it, but I am happy if it is more durable that way.

[Box'a'bits]

Is the white and blue bike in your pics Redboots bike? Do you have any other info on that bike.
It looks like it has an 18inch rear wheel.

No, Redboots bike is a R100GSPD Classic. Here's his blog page. He's put WP 5060 forks on it, with a triple clamp from Boxer Toko (Matt Beekers).

The blue bike is a 'random' I liked from the 2v GS forum (de). There are more pictures of the bike in my Picasa album here. Note your bike takes pride of place on the album cover.

How do you find the handling/steering on your bike with the USD forks clamps, compared with the original clamps with the greater offset ?

Very good. It stablises the bike. EddieB said it feels much more planted. Certainly there is a noticeable difference offroad & in gravel. Given the tank, I don't appear to have lost steering lock. I think the differences in feel are attributed the combination of the whole, rather than individual bits - ie to the skinnier rim size, reduced offset, stronger forks, & a whole lot less weight. The downside has been the brakes, & the time spent setting up. Also that fact that it has worn through seals & bushes rather fast (albeit I made a mistake using All Balls parts).

Not sure what way I would like to go if I do another mod on the GS, use the smaller offset clamps and do something with the tank to get some turning clearance or get some of the HPM guy clamps. Hmmm.? I feel a project coming on ! !

Migsel modified his tank. Here's the posts 1 & 2

If I was to do it again, & didn't have my eye on taller suspension, I might look at the Racetech (de) inserts that Kokopelli got in. Then you have a stealth look, & don't have to worry about the ancilliaries. But I see Koko & a lot of the others that did that purchase don't yet seem to have these things up & running, so....

I guess it depends on what you want to use the bike for. Weight & ground clearance are certainly issues.

[Box'a'bits]

The driveshaft on this bike has quite a steep angle. My understanding was that they used a short shock on the R80GS Basic to make the assembly more durable. I guess if you want performance and you are prepared to repair or replace components, it doesn't really matter. The Basic always looks like it's squatting, I can't say I like it, but I am happy if it is more durable that way.

I think the answer to that is maybe to look at aftermarket driveshafts with the greasable (& replaceable) universal joints.

Also, remember when the bike is being ridden, there will be some suspension sag.

Finally, I think the taller bike maybe end up with braced frames etc & maybe get ridden harder, & therefore have greater maintenance cost expectations.

[Subike]

Dont know much about these bikes, but got a pic of one that ticked a few box's for me ( pun)
Seeing as the last few posts have been about off rod variants, I thought this was relevant

[Kokopelli]

Dont know much about these bikes, but got a pic of one that ticked a few box's for me ( pun)
Seeing as the last few posts have been about off rod variants, I thought this was relevant

That's a well known bike. Probably the most extreme airhead around. Check out the video on utube.

[Box'a'bits]

That's Manuel's from SWT Sports. Its changed again this year - he's cut, realigned, & rewelded the bottom frame tubes to allow a more linear engine / drive shaft.

Here's some frame & other pictures, & a link across to his 2v - GS thread



Whilst I am sure the utility of the bike has been getting better for the twin cylinder enduro racing he does, the aesthetics have started going down hill..

[Subike]

That's a well known bike. Probably the most extreme airhead around. Check out the video on utube.

Hey thanks for that, checked out the vid, and awesome is all I can say.