BMW F650GSR - Rallye Project Bike

Pirelli MT 21 Rallycross 130/90x17...

I agree that in most cases an 18" rim exchange from a 17" should give just 1/2"...you are, after all, dividing the 1" by 2. That being said I've read from others that you can get as much as 1" from the deal. Those claims were made based on actual measurements, IIRC.

I have not put my whole faith in those claims just as I have not bothered to do the calculations myself on a variety of tire sizes.

I'm interested in the 18" rear wheel for what 'extra' height I can get over the 17" AND for the better tire selection.

I believe that if the rear comes up short I can raise the forks to make up the difference.



-BTW, I had a look at your LC4 tread dealing with the engine swap...its going to take me a while to read that one. Looks fun.

Based on my experience and satisfaction with the F650GS rotax motor, if I owned an 640ADV, I'd be trying to find a way to dump the LC4 motor too. But because I own the Dakar, I'm investing in that chassis.

-cheers

Okay, that looks different. That isn't what I saw on plumby's bike; his was shiny. Do you know if the post 2002 dakar riders on F650RR's pioneered the change to the LHS engine case to allow for the clutch basket removal?

Did this guy in South Africa swap engines or just the case?

had a look at the fiche for the G650X-challenge




The BMW price for all of the parts on this page is ~$430USD with $220 being #1 and $130 being #3

-pretty spendy for an upgrade to an old motor...the average sale price of a used F650GS engine here is about $750.

Maybe someone could pull exact dimensions and do a tracing of #1 for me when their motor is apart. I know that I could get someone to mill #1 for me for far less $$$ and I could buy #3. Maybe I could save ~$125 that way.

Anyway, this isn't important right now. The clutch isn't a problem I have just yet.

-still interested in knowing what was on the SF bike.

You can do that with the OEM cover though. Same way you can change the water pump without dropping the oil. Just lean it to a wall or post at about 10-15 degrees.

I think the point of the revision to the LHS engine case wasn't just a matter of avoiding the an oil drain. It was to quicken and simplify the process of getting at the clutch.

Removing the LHS engine cover on the 652 engine is a PITA. Its held on with a bunch of bolts and has a really big gasket that is easy to tear. And you have to remove the oil pipe to get it off unless you have replaced the pipe with a flexible line and routed it to avoid the interference with the case.

Having replaced two water pumps I can see the benefit of the case revision in terms of clutch service. The new case allows unobstructed and simple access to the clutch. The gasket can likely be reused a bunch and would be easier to manage. No crush washers to replace since you're not touching the oil pipe. The only challenge is getting the rack and pinion alignment when putting it back on...something probably a lot easier to do when you don't have to align such a big case at multiple points.

The revision makes sense

have a look on this page:

http://www.rgengineering.co.uk/charleyboorman.html

yep...looks familiar



I wonder what that outfit would sell those for if they did another batch.

I'm not into the bling aspect of their unfinished product; something more OEM-like is what they originally had in mind. That would be to my liking.

My guess would be....more than a brand new BMW part.

I am going to wait a bit untill people start binning their X-challenges. Plenty of X-motos in the scrap heap though.

-some answers to some Q?s
　
In terms of parts selection during the thinking stages I started looking for 640Adventure bits early on because I figured it was closer to the F650 specs than the 950. It turned out that Komatias had already done the 950 swap by the time I started shopping so his feedback on the install drove me to the 950; it turned out that I couldn't find any 640 parts anyway. I don't know much about the 640ADV clamps and I'm not sure that they would be suitable for use on the F650. One might be able to go that route because the forks are pretty much the same thing as the 950 forks; I believe the parts are identical for the late model 640ADV bikes and the 950ADV, just sprung differently. The hub and axles are the same too. I know that the 640ADV is lighter than the F650 and the 950ADV is heavier; it is possible that one solution is over sprung and the other under sprung for the F650, but I've read a trend that the 950 tended to be under sprung. If so, that would make the 950ADV front forks almost spot on for the F650. That is the word anyway and I am looking forward to validating it.
　
-The front wheel off a 640ADV would be a 1.6x21 just like the F650. The 950 uses a wider rim...which is why I went with a 640 front wheel. The hubs for the late models are identical because the 640s picked up twin discs in 2006.

I purchased most of my kit from an inmate here, forks, clamps, axle, spare front hub, brake calipers and mounting brackets; got the wheel from an inmate here; got the Emig handlebar clamps from an inmate here (so I could run the heated grip wires out the bottom of the handlebar-stock handlebar clamps have a solid member on the bottom that would interfere with this); got the steering stem from an inmate here; you get the idea.
After I committed to buying my front end, I found an even less-used 950 front end on ebay that sold for a touch over $500-clamps, forks, handlebars, axle, front brake master cylinder.
Anyway, they don't come up as often as the yami stuff, but the forks and clamps are out there.


Regarding the iead of using the F650 master cylinder to drive twin discs in the front, it won't drive them enough to give any better braking than a single disc. This is because the master cyinder can only move so much fluid to the calipers; that fluid will get distributed to both calipers equally such that neither set of brake pads will really clamp down on the discs like one would want. The end result might be with the same net braking effect as a single disc setup. Best case scenario is that it would give a bit more braking effect with the original master cylinder, but that would be at the cost of modulation with the lever...the lever would end up going all the way to the handlebar and it would feel funny or bad. I just don't think there is any way to get around this problem without going with the master cylinder for the KTM.

-there are issues with getting that master cylinder to fit on the BMW combo switch housing. But this should not be a discouraging remark, however...there is a solution and it can certainly be found.

Regarding the idea of using ABS on the WP front end, the ABS ring can be fitted to the KTM hub. I put it on my front hub on Tuesday...it could be made to work by fabricating 6 clips that would bolt onto the ring and slip over the hub. I figured out that this could be done with a single piece of machined aluminum and cut into 6 clips for the 6 bolts on the ring. The bolts would nest nicely between the brake rotor bolts so that it would end up looking like a 12 bolt pattern on the ring side of the wheel. This is a pretty simple deal...the front wheel sensor would be an easy thing to sort too once the ring was in place. ABS should be little trouble.

Regarding the steering stops and steering lock, yes I got these both to work out. When I did this I really didn't have a reference point because Komatias had not needed the steering lock and he solved the steering stop issue, at least initially with some padding between the fork tubes and the frame. I decided I needed the steering lock to work like it originally did and I wanted to make use of the adjustable steering stop bolts on the lower 950ADV triple clamp. For the lock, I welded a curved piece of steel on top of the original frame-mounted steering lock and mounted the BMW key holder in the KTM position on the clamps. The result there was that I had to notch the right side of that piece of added steel and put a hole in the center of it. The handlebars now lock at left and right as before, but the holes are in the middle and right edge rather than the symetrical orientation of the original. Later I saw that the guys on Garagenight.tv did a much better job of this than me because they achieved the same result with two pieces of machined steel that bolt onto the frame instead of being welded. I like their solution better but the results are the same.
-Kiwi Pete over at garagenight.tv had an altogether different solution than me for the steering stops. His steering stop solution was more trial and error than mine and utilized the original steering stop on the frame, which is a non-adjustable solution. While I thought about doing something to the lower clamps to utilize the original bump stops on the frame, I knew that I would end up needing that area for a new front fairing bracket. My solution was to add a piece of steel to the frame and use the adjustable steering stops on the lower triple clamp. This works well, in my opinion, but in my case I didn't make the piece of steel big enough to give the best contact area to the steering stop bolts...still it works. As it stands now the bolt heads on the lower clamp strike the steel bar just off center so that there is a bending moment on the bolt. I might add more steel down there later if it turns out that this causes the bolts to bend. I believe it would take a serious hit to do anything to the bolts, so I'm not to worried about it since I plan on taking things easy during the break-in period. I believe my solution is sound.and I will be able to add more contact area for better alignment on the bolts if I need to.


Another thing I didn't mention earlier deals with offsets, or how far forward of center the forks are from the steering tube. I know the 950ADV triple clamp offset is 18mm. The 950SE is 20mm. I don't know about the 640ADV and I also never measured the stock F650 offset. Anyone have any offset specs on the F650GS and the 640ADV? I have my original top clamp lying around and I'll see about measuring it at some point.

There are plenty of threads about offsets elsewhere in the forum, but my $0.02 is that the F650 could use more offset. If 18mm is a bit more than stock, great-I'll get that with the 950ADV clamps. It will take some testing to see what the best solution is before I can speak about the idea of going with 20mm offset clamps like those found on the 950SE. I'm hoping that I can contribute some feedback along with Komatias, Kiwi Pete, and Wanyne down under. Maybe we can 'normalize' our data somewhat and sort out how the varying options affect the handling of the bike..?

-it is worth stating that if the 640ADV has less than 18mm of offset, it is unlikely that this would be suitable for use on the F650 regardless of what the stock offset dimension is. This is because the forks would end up limiting the steering angles. As it is now, the 18mm offset 950ADV clamps will fit on the F650 if a bit is cut out from the front fairing bracket to give clearence to the fork tubes. The loss with this isn't material, however, is in steering angle because the forks are so big up top that they end up bashing the frame before the original steering limits are reached. With less than 18mm of fork offset this steering angle loss would be too great IMHO. The steering loss is small enough with 18mm of offset on 48mm WP forks that I don't worry too much about its impacts on the bike...manually pushing the bike around tight spaces is probably where it will suffer the most. I don't ride in the woods enough to need to worry about an extra 15 degrees on the trail, or whatever it is. We should collectively measure the resulting steering angles with the 950ADV frond end!

...back to the 20mm offset. If the stock offset of the F650 is 18mm, then 20mm would probably feel great and with that one would get back some of the steering angle loss. To my knowledge, the only options for 20mm offset triple clamps are the 950SE clamps and the aftermarket kit sold by Gary Emig. More on that later I guess.

Most 03-07 EXC and SX triples are 20mm offset and will fit the 48mm forks. They use solid mounted bar clamps. I have an extra set if you can't find any locally.

640 Adv has 18mm offset.

The 640 Adv with the twin disc hubs (04-07?) comes with an 1.85" (or even 2.15"?) Behr rim, which will bend very easily. If you ride offroad you want an 1.6" Excel (A60 is best) or DID DirtStar.

Its good to have confirmation on the 640ADV offset as well as info about the rim sizes. I thought I was sure the front rim was a 1.6"x21, but I see my error. I guess I should measure mine and see what I have, its either a 1.6 or 1.85 custom Excel jobber.

I have an SX lower clamp from which I extracted my steering stem; I knew that it was for a 48mm set of WP forks, but I forget why this was not originally an option...?

I know the SM clamps are too wide to fit; maybe the SX was on the narrow side and required a different hub and assorted spacing? I remember, it wasn't so much that an SX setup wouldn't fit, it was that I didn't want to mess with suspension tuning. My aim was to get something close straight out of the box and the 950ADV was the right length and close to being sprung correctly.

Maybe the SX stuff would fit, I'm not sure.

No need to measure the rim, the size is engraved on the inner part of the ring.

Only a few years of the LC4 SM models used wider clamps (210mm), but they also have a wider left fork lug that only fits the gold 4 piston Brembo caliper.

All SX and EXC as well as most LC4s have 190mm fork tube spacing, I am pretty sure that the LC8 has the same? If so, all spacers hubs etc will interchange (watch your axle size though!).

Not sure how heavy your bike will end up being on the front, but you probably want a .50 -.54 spring depending on your weight. I think the 950 came with .48 stock which is undersprung for 99% of riders.

The 640Adv and 950 Yokes are the same part no's with the exception of the SE noted above

There is a choice of 18 or 20mm offset on the SX Yokes & as LukasM points out most were 20mm. The F650GS is 21mm offset

Re fork width even back to the 20mm axle 4357's width is 190mm

Re fitting the SX yokes to the GS, the 950 yoke is actually easier as it mounts the ignition switch a couple of mm further forward & the adaptor plate Sellmeyer & garageTV use is the simplest, The SX yoke will work but adaption is needed, will post some pics on this in the future.

The SX front wheel takes the 950 300 mm front disc and the 950 caliper hanger fits the 4357

The 950 caliper is the same as the GS, a big thanks goes to Sellmeyer for his assistance in confirming the calipers

Re longer length of the 4357's this is simple to change for the GS, use the 35mm rebound spring with 24 mm spacer, it reduces fork length back & reduces travel at the same time to 260 mm, there is a further 17-18 mm travel reduction possible by adjustment in the hydraulic stop position, again done by fitting a spacer.

Hey Wayne, thanks for chiming in on this.

Can you tell us what model & years of the KTMs featured the 4357 forks? I don't even remember what model I have.

4357 is just the model name of the old 43mm forks. The 48mm ones are called 4860.

I think the very nice billet adjustable offset (18/20mm) clamps were stock on 05-09 SX bikes, maybe Wayne can confirm?

The KTM's fitted with 4357's are

2000 to 2002 - 250, 300, 380 SX, MX, EX
2000 to 2002 - 400/520 (4860 optional in 2002)
2000 to 2005 - 620/625 SX
2000 to 2005 - 640 Enduro

I think some of the 85/105's also run them but did not look as I was interested in the larger capacity machines with the SX yokes. There seem to be differences in those under 125cc

Re the later models & adjustable yokes, dont know, The 06 & later have the newer style closed cartridges & I was tracking the valving & valve body changes on the open cartridge forks.

I posted into the thread below the details on how the valving changed between year models on the 4357 & 4860's. I found different people had little bits of the info but no one had compiled all the info into one place

http://www.advrider.com/forums/showpost.php?p=11897855&postcount=43

The thread also has some good information on shimming the LC640Adv which is the closest in weight to the GS.

Have put all the valving data into a spreadsheet so can email it to anyone who wants it

Edit - Forgot, I did see one of the US KTM dealers dumping a large volume of stock as specials including a lot of the adjustable yokes when I was doing a search not long back. They were all for 4860's & I have 4357 so was not relevant to me

Found a thread over on wilddog forum about another WP 4357 conversion worth taking a look at

http://www.wilddog.za.net/forum/index.php?topic=27759.0

How you doing? This all looks great. I have a F650 RR an its awesome.
One thing I think you might want to keep in mind is the Rallye Fairing is really made for standing on the pegs. With that being said keep in mind the height of the fairing when your sitting down, you cant see through the fairing.
My bike has a 40 inch seat height (which sucks!!!!) and at 5' 7" lowering the seat....makes the fairing a bother. Just a thought.

Milk Budda

Any chance of you having info on the WP rear shock on your machine ?

There is considerable confusion re shock length & stroke out there, any info like WP Part No, length, stroke etc would be greatly appreciated

Did you get owners manuals for the forks & shock ?

BTW, nice machine, what are the side bags you are using ?

For what its worth, my WP owners manual doesn't say squat about my shock. I don't know what spring is on it nor what stroke it offers. I'm pretty sure it is setup with the same stroke as the OE Showa for the Dakar and the model offered by Hyperpro. I'll dig it out again and have another look at it just to be sure.

I'll bet that the RR shock on the white bike is the same as what is offered on the TT site...I think they list the spring but not the stroke. They claim 250mm of travel at the rear, but one would have to do the math to get back to the stroke...I believe the equation is linear, so this shouldn't be hard to sort.


Those bags look like wolfman up on the seat and Ortlieb on the sides for panniers. I think the panniers are the same as what are sold for bicycle use.

I get what you are saying about the fairing height; I've been considering this and trying to come up with the best compromise. I have been riding with the single spark tall Dakar screen with black paint on it. I don't see through it, rather over it...for me, I know I can go higher.

Two considerations:

1) I figure I can go higher without obstructing my forward view too much; I don't need to increase the height too much to get better wind protection. Also, if I widen the profile a bit that will give me more room for instruments behind it than what I get with the tall screen.

2) I am also thinking about making the top half of it clear. I've seen how others here have formed their own plastic screens using heat guns and they seem to get pretty good results. Right now I'm not clear on how good the optics would be if I used my mold to do the shaping of the plastic...in the past I have not had great luck with aircraft canopies doing this but I am willing to make a fresh go of it.


One favor, if you don't mind.

Can you measure the height of the top edge of the TT fairing? The measurement which would mean the most to me would be one that I can normalize and repeat on my bike, this means factoring out the suspension from the equation.

I'm thinking that you'd need a plumb line, a few pieces of tape, and a 2' or 3' level; maybe an extra set of hands. I'm interested in the horizontal distance between the rear swingarm pivot point and the vertical line at which you measure the max height of the fairing, plus the vertical measurement from this line to the top of the fairing.

Start with the plumb line taped to the tallest part of the fairing and hanging over the side of the bike; if possible use a stick or something taped to the fairing to get the line out over the edge of the bike so the plumb line is vertical and thus providing an accurate measurement later.

Next use the level to set the horizontal reference point from the plumb line to the rear swingarm pivot point. Mark the points on the level where the pivot point and the plumb line are using tape. This horizontal measurement is made with the level, level of course. Next mark the point on the plumb line where the level meets it; measure from that point to the top of the fairing and that is the vertical measurement.

-I can reference these two dimensions against what I have got and see where I stand. I'm thinking that I'll be a bit lower than the TT setup, but it would be nice to know for sure.




BTW, how can you manage to ride the RR being only 5x7? Is your suspension lowered...? obviously not if you have a 40" seat height. What is the whole story?