Boxer shaft details

BiKenG

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My question really relates to any pre water cooled motors, i.e. those with Right Hand Drive (drive shaft on the RHS).

I want to use a BMW paralever setup on another bike, but lining up shafts and wheels etc is not easy. I currently have an R1100GS swingarm and K1100 final drive (bevel) unit, but I wondered if anything else might be better suited.

Does anyone have any data relating to the offset (from bike centreline, e.g. rear wheel) to the output shaft on the engine and also to the mounting face for the rear wheel and hopefully to the swingarm pivots. Or is there anywhere from which I could obtain such data.

How does the latest R1200 RHD assembly (which used the different Final Drive Unit and torque arm above the S/A) compare to the earlier ones (torque arm below the S/A)? Things like weight, length etc. I'm wondering whether that later setup would be more suitable for my purposes.

I have a lot of experience with Hondas, but virtually none with BMWs, so hope someone can help.
 
My question really relates to any pre water cooled motors, i.e. those with Right Hand Drive (drive shaft on the RHS).

I want to use a BMW paralever setup on another bike, but lining up shafts and wheels etc is not easy. I currently have an R1100GS swingarm and K1100 final drive (bevel) unit, but I wondered if anything else might be better suited.

Does anyone have any data relating to the offset (from bike centreline, e.g. rear wheel) to the output shaft on the engine and also to the mounting face for the rear wheel and hopefully to the swingarm pivots. Or is there anywhere from which I could obtain such data.

How does the latest R1200 RHD assembly (which used the different Final Drive Unit and torque arm above the S/A) compare to the earlier ones (torque arm below the S/A)? Things like weight, length etc. I'm wondering whether that later setup would be more suitable for my purposes.

I have a lot of experience with Hondas, but virtually none with BMWs, so hope someone can help.

Try asking Mikey or Steptoe,

They have oodles of experiance with the marque
 
A visit to either or both would solve your problems as they’ll almost certainly have parts you can measure for yourself.
BTW the GS and RT have different offsets to accommodate different tyre widths. I don’t know how much but it’s probably but a huge amount.
 
What is your purpose?

What are you trying to achieve?

Which engine?

My purpose is to find out if a BMW paralever Single Sided SwingArm can be used on a couple of other bikes so that I can achieve the desired result of having a SSSA on those bikes.

No offence meant, but I just want to find out as much data as I can about the various BMW RHD Paralever SSSAs (e.g. offsets etc) so I can determine what might be possible. I'm sure it won't be a simple swap and I expect some machining will be required, but dimensional data such as I'm after will enable me to determine where best to start - or indeed give up completely. :)

One crucial criteria is that it uses a single central monoshock. So those bikes that had the shock on the RHS mounted just above the shaft are not suitable. It has to have the central shock mount as many do.

I hoped someone might have a chart showing all this sort of data for many, or most SSSAs.
 
The 1200 has a single central coilover shock with no rising rate linkage. The actual swing arm is a hollow aluminium casting.

The final drive has a parallel linkage that avoids the suspension jacking that happens on the old Airhead boxers. However, it causes suspension dive under power that can make pillions feel seasick.

The Yamaha Diversion 900 has a solid shaft final drive (on the left) but does not jack the back end under power. I believe that's due to the rising rate shock linkage. Any wear in that linkage will cause what feels like transmission backlash as the swing arm tries to extend the suspension.

No knowing your plans we cant really give much help. However you might find this useful. http://www.realoem.com/bmw/select.do
 
I really don't want to upset anyone here, but I don't understand the problem. It is of NO relevance whatsoever into what bike(s) I am considering trying to fit a BMW Paralever SSSA. Whether it is worthwhile or not depends entirely on my desire and abilities and of course mainly the dimensions of the BMW parts (thanks for the parts link, but of course no dimensions given there). I am not asking for advice on what others may think of the idea. Those decisions are mine to make, based on the aforementioned criteria and that dimensional data is absolute and does not depend on the potential recipients of the BMW items.

Like I said, I'm trying to explain this without upsetting anyone, but I have to say again, the identity of the intended recipient bikes is irrelevant. Not secret, just irrelevant. However I would be very grateful if anyone could supply (or provide a link to) the following data for e.g. R1100, R1150 and R1200 (pre LC):-

length of S/A from wheel centre to pivot centreline
offset (from bike centreline, e.g. centre of rear wheel rim) to:
• the output shaft on the engine
• the mounting face for the rear wheel
• the swingarm pivots each side

If I can obtain the above data, then I can make the decision as to what viable options do or do not exist. I really would be most grateful if anyone could help with this.

However, to satisfy anyone's curiosity, I am working on 2 projects for which I am looking into the feasibility of fitting BMW SSSAs. They are both Hondas, a CX650 and a GL1000. See, makes no difference to the data I need. :)
 
Some specific requirements thanks

For the 1200 Adventure 2008 -

Swing arm pivot to wheel centre 530mm
Adventure wire wheel rim width 132mm. RHS rim to wheel mounting face = 33mm. Offset from centreline works out at 33mm
Presumably the cast alloy wheel is similar but can't confirm with wheel on bike.
Tyre clearance to swing arm 20mm approx (150 section tyre) Measured with fingers in the gap. Crude but all I can offer with the bike in use.​

With the bike in use I can't give useful swing arm width to the wheel centreline or any of the drive shaft to chassis dimensions. There is no easy access to some parts and no reliable datum to work from.

As already said, Mikey or Steptoe should be able to help as they're likely have loose parts for you to measure and weigh. Also talk to MotorWorks and James Sherlock who break these bikes for spares. I've always found them very helpful.

As a matter of opinion (for what that's worth) you could do a lot better (in engineering terms) than the Hexhead 1200 final drive. It's quite pretty but it's also fragile and parts cost a fortune. My 50,000 mile FD rebuild including new internal bearings, new trunnion bearings and new Hardy Spicer in drive shaft came to well north of £700 from a well respected service engineer.

The simple CX500 style final drive on the Diversion 900 (I know it's the wrong side) had done 75K with nothing more than oil changes and a new set of swing arm bearings. It also did not jack under power probably because of the rising rate suspension linkage.
 
All good to know, thanks.

Are you saying that the Hexhead 1200 final drive is not as robust as the earlier ones?

A LHD system is no good for either of my projects which both require RHD. Swapping an FDU from L to R has been done but it's not how it was designed and not something I'd contemplate. I like the BMW system as it's single sided monoshock, but I need the dimensions before wasting money on something that'll never fit. I had hoped to use a GL1800 rear end as it's SSSA and from a Honda so ought to be an easier fit. Nope. So hard it's basically impossible, whereas I KNOW an R1100GS S/A will fit in the CX frame. Just not sure of the offsets yet.

BTW, rising rate rear suspension won't have any noticeable effect on power jacking. It's more to do with geometry of the S/A and drive shaft etc. Honda's VFR1200 has no fancy Paralever and/or torque arms, but the offset drive shaft eliminates jacking under power. Yamaha have probably done something similar.
 
Give me a couple of days and i can give a couple of measurements, i've an 1150 GS swingarm with final attached currently laying on the garage floor.
 
Give me a couple of days and i can give a couple of measurements, i've an 1150 GS swingarm with final attached currently laying on the garage floor.

Hey Steptoe, where exactly are you in SW London. Not far from me and I could call over and see some bits. Might help?
 
Are you saying that the Hexhead 1200 final drive is not as robust as the earlier ones?
Yes. The 1150 design is similar to the old BL Mini front hub. The 1200 relies on a deep groove ball bearing at the wheel side with needle roller at the other side. Steppers will give the full details on that. All bearings on mine were worn out at 50K. Gears were fine.

BTW, rising rate rear suspension won't have any noticeable effect on power jacking. It's more to do with geometry of the S/A and drive shaft etc. Honda's VFR1200 has no fancy Paralever and/or torque arms, but the offset drive shaft eliminates jacking under power. Yamaha have probably done something similar.
Interesting as that was my opinion but apart from the shock linkage, the old Diversion 900 swing arm is about as simple as it gets. It did not jack the back end. The predecessor XJ did jack.
When the needle rollers were worn (as they did rapidly), the Diversion 900 suspension made a clunk that felt like drive backlash. It was the swing arm trying to lift the back end but beyond that there was no lifting.
The shock itself was the cheap jack OEM unit.
 
Are you saying that the Hexhead 1200 final drive is not as robust as the earlier ones
Perhaps not as robust or reliable,but a lot lighter and better looking,
poss easier to find a decent wheel as well
A swingarm can be bought for notalotacash,the driveshaft and fd is another matter.
But both can be refurbished as long as they are not trashed.
Cannot really help beyond that ,I’ve never had a need to take any measurements
I do have a 1200 police spec final drive in bits that needs refurb,
Gearing is 1/2 way in between an rt and a Gs
 
...but a lot lighter...

Aha. Really? That's the sort of thing that could make a difference. The reality is that these will not be long distance/high mileage bikes so other factors could be higher priority.

Measurements will be crucial however. I'm pretty sure the length will be ok, it's the offsets that are crucial.
 
So, wheels.

Is the mounting and offset of all the RHD bikes the same, so any rear wheel will fit to any Swing-Arm? Ignoring disc mounting, but is the mount bolt PCD all the same and are all the wheel offsets (centre of rim to mounting face) the same?

In other words, if I'm looking for a rear wire spoke wheel, does it need to be specific to the rear Shaft/Swing-Arm/Final Drive Unit?
 
Regarding my last post, further research indicates to to me that for the 1100, 1150 and 1200 (RHD) GSs with wire spoke wheels:-

• All the front wheels are basically the same.

• The 1200 (with the later type final drive assembly) has a larger PCD for the mount bolts of the rear wheel.
In any case, this SSSA uses an offset shaft (like Honda's VFR1200) to avoid jacking. Although those later types look good and are apparently lighter, the offset shaft makes them unsuitable for my purposes as my bikes both have output shafts in-line with the swing-arm pivot and I'm not about to hack the frame(s) to move the pivot point.

• The 1100 and 1150 GSs look like they have the same rear wheel mount and PCD.

• All GS wire spoke wheels have Al./alloy rims.

If any of the above is incorrect, please let me know.

Otherwise, looks like the 1150 and 1100 rears and either 1100,1150 or 1200 fronts would be what I'm after for the wheels, but still need some dimensions for those S/As. The only data I have is for the 1200 which as mentioned above will be no good, so any other data would be much appreciated. I'm more than happy to pop over to Steptoe's place and have a measure up myself if that would be ok.
 
Not sure how the rear paralever fittings will affect your plans, they're completely different in many way and mounting points between the 1150/1200 models.

As are the front wheels.
 
Yes, I've determined the 1200 rear end will not be suitable. But are the front wheels not the same? I've been looking at lots of pictures and apart from rim colour differences (some black, some silver), they do all look to be basically the same. If they're not, could you please roughly explain the differences? I'm not concerned about ABS ring or not as that would be removed, but the hubs otherwise all the look the same.

Steptoe, if you have a lot of this stuff lying around, is there any possibility I could pop over to have a look? It would enormously help me to get a handle on all these differences.
 
The rear wheel is similar to a car wheel bolting to the hub with 5 bolts. The front is like any other bike with a spindle mounting. The spoke styles are similar but rim widths also differ.
 
I have so far totally failed to find the PCD of the R1100/1150GS rear wheel mount. Seems ot be some sort of secret.

Anyone help with this?
 


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