21 inch front on R11XXGS anyone?
 

hey g'day.

has anyone put a 21" front on one of these? actually, i know it has been done as i have seen one, but would like to know some details if anyone has them.
i want 21" tubeless, and hopefully will keep the twin discs and abs.

• do you have to use the original hub and lace the wheel to it?
• are there any spacing issues, either to the guard or in terms of forks / discs etc.?
• where to look for such a rim?

hopefully someone out there will tell me it's easy...
cheers,
andy

Yes it has been done .. but I'm not sure if it has been done to a X spoked tubless rim .. you cannot buy one of them easily. Best bet would be off an R100GS .. but before you do that - count the number of spokes and see if that is the same as your wheel .. if not then they won't match up ..

The ones that have been done are probably to a normal tube type rim ..

21 inch tubless
 

HP2 uses a 21" Behr tubless rim. Don't know if it is available from Behr. I imagine Woody's can fix you up.
Mike

Shipping cost from Woodies might be a bit much .. he is in Australia... (and Woodies is in the USA)

Think bm has the patten on the X spoked .. so the actual manufacture may be constrained to only supply bm. Motoguzzie use the same system under licence from bm...

Some people have motared HP2s (I'd forgotten them as 21 fronts) - might be able to get a wheel off them ? Good luck .. the other HP2 alternative is to buy it from bm ($$$)

this works
 

hi andy
both r1150gsadv and r100gs use 40 spokes
if you use your hub and r100gs spokes and rim it will work fine.

i only know this as i am building two wheels for my sidecar outfit and doing this job the other way round r1150gs adv rim and spokes onto a r100gs hub.

the wheels are a pain to make mind!

hope this helps

Iain

ps will have a rim 21" left over but am in UK

Just a thought...
 

I can't remember where the speedo drive runs from, but if its from the fonrt wheel, you may need to think about how to gauge you speed, and how to kepp actual mileage accurate....

I had this issue going from 21in to 17 on a SM...

i think that all r series engined bmw,s have the speedo driven from the gearbox, i could be wrong

Sorry but I think you are wrong too :mchappy: only because I have replaced 2 speedo cables on my R1100GS over the years and they definitely go to the front wheel directly via the speedo, do not go via the geerbox, do not pass go and do not collect £200 :smartass:

Some of the boys on the Dutch GS forum have done the 21" conversion but their site is all in Dutch . Google GS club Ndereland and you'll find them .

He is thinking airheads are the only R series .. bm did not change the designation when the went oilhead.. same with the K series when they turned the motor around and F series .. should be more series to seperate the different models out more ..