Cast Wheel Conversion Help

[clivewhilde]

I've read a few threads but I haven't got my answer so need some help if possible please. My problem is with the fitment of the cast front wheel.

I've fitted 5 spoke cast RT wheels to my 2002 R1150GS (single spark). I've been running a 17" spoked front for a while using a GS hub and a Megamoto rim so I have the correct speedo etc.

I've had the cast wheels powdercoated black and bought from Motorworks new bearings, internal spacer, speedo dog drive and seal. I've swapped the discs over and fitted a pressed steel ABS ring.

When I assemble the wheel it all goes together well until I tighten the axle bolt and it pulls the wheel over to the left of the bike and locks it up. When I release the axle bolt the wheel centralises (you can see an equal gap between the disc bolts and the fork legs) and it all spins nicely. There seems to be a 1.5-2mm gap on the axle between the speedo housing and the inside of the fork leg. I suppose I could space it out with a washer but nobody else seems to get this problem? I thought maybe I needed the RT axle but again it appears that the original GS axle is the one to use.

Am I missing something? Has anybody else experienced this?

Thanks

 

[Steptoe]

is the Rt wheel from an 1100Rt or 1150RT ?

 

[clivewhilde]

1150RT

 

[Den]

Wrong speedometer drive.

Left wrong. right correct

http://www.ukgser.com/forums/attachment.php?attachmentid=92480&stc=1&d=1211370081

Read THE thread. http://www.ukgser.com/forums/showthread.php?15702-Cast-Wheel-Conversion-The-Facts!/page4

 

[clivewhilde]

Don't think so, it's got the 17" speedo drive on already. It was running a 17" spoked.

 

[Den]

its still gonna be your speedo drive

 

[clivewhilde]

The thread suggests a 2.5mm spacer.........

Also if anyone is interested I weighed the wheels on bathroom scales that go to the nearest 0.5kg. The rear weighed the same with 170 tyre instead of 150, front was 1.5kg lighter.

 

[clivewhilde]

its still gonna be your speedo drive

Can you explain that please? Is there more than one 17" speedo drive?

 

[Den]

Can you explain that please? Is there more than one 17" speedo drive?

Spoked hubs have a different drive, regardless of size of wheel. If you would take a second to look the picture I posted, which took me 5 minutes of my precious time to find, you will see the difference.

 

[clivewhilde]

Den, don't get me wrong, appreciate the help, just trying to understand.

The differences in the picture seem to be inboard towards the centre of the wheel. The face of the drive still butts up against the seal and looking at the picture (hard to tell) the drive shoulders appear to be at the same height?

I have bought a different drive which has the different ratio. There are two 2.6:1 drives on motorworks, one for the 1150RT and one for the 1100RT. I'll whip mine off and see if I can see a part number.

 

[Dragon Master]

When I assemble the wheel it all goes together well until I tighten the axle bolt and it pulls the wheel over to the left of the bike and locks it up. When I release the axle bolt the wheel centralises (you can see an equal gap between the disc bolts and the fork legs) and it all spins nicely. There seems to be a 1.5-2mm gap on the axle between the speedo housing and the inside of the fork leg. I suppose I could space it out with a washer but nobody else seems to get this problem? I thought maybe I needed the RT axle but again it appears that the original GS axle is the one to use.

Am I missing something? Has anybody else experienced this?

Thanks

Look at Den's picture again. On the right-hand (correct) drive, the centre bush is longer than the one on the L/H (incorrect) one. I'd bet about 2mm longer. It will hold the speedo drive 2mm further out from ther bearing (or what ever it butts up against), so taking up that gap you have between the speedo housing and fork leg..


I think. But I didn't even know what day it was when I woke up this afternoon. (Due to working nights, not alcohol...

 

[clivewhilde]

Thanks to all, got back from working away this week with a new speedo drive from motorworks waiting for me on the doormat. The differences are exactly as posted in the pictures from Den, wheel bolted up and all is well with the world again.

I've attached some pictures......

At first I thought I had a black speedo drive that would match the new wheels but it just needed a fgood clean!!!

 

[clivewhilde]

Then I dug out the old 19" wheel drive to see what the difference was, and as you can see the housings are identical. However the drive inside is not; the white driven gears are a different diameter and are not interchangeable between housings. There is some writing on which I can tell is different but my eyes aren't good enough to see the letters numbers (and neither is my photography).

The only mystery that remains for me is what speedo drive did I buy to fit the spoked 17" wheel that is a one off I had built myself - damned if I can remember. Can only think it was a Megamoto HP2 drive but do they even have a mechanical speedo? - otherwise what other model BMW is there that has a spoked 17" front

Anyway - thanks to everyone and the thread can now be closed with a picture of the bike with its new wheels

 

[Littledumptruck]

Some of the R's get spoked wheels, although I thought they were 18", but maybe they run a smaller tyre, or the difference in overall diameter is small enough not to need different gearing in the drive

http://www.motorcyclespecs.co.za/model/bmw/bmw_r850r 94.htm

 

[clivewhilde]

I'm selling my HP2 rim built on a R1150GS hub on ebay.

Item No 231258220301

http://cgi.ebay.co.uk/ws/eBayISAPI.d...m=231258220301

Comes with innertube and correct speedo drive.