Recommend me a C spanner

Posh Pete

Still got a pulse.
UKGSer Subscriber
Joined
Dec 29, 2005
Messages
19,234
Reaction score
992
Location
Embra, Scotland
About to do some work on the R100GS front forks. On earlier airheads, fork tubes used to be secured by a large hex nut. Not on the GS which uses a notched nut requiring a C spanner. Naturally, the one in the tool kit does not fit! :blast

So I need a robust C spanner of the right size. Any suggestions?
 
Perhaps a pic would help. The top of my fork tubes (1992) are a large hex nut.
 
Motoworks have a 'pin spanner', half way down this page. Is this what you are talking about perhaps?

https://www.motorworks.co.uk/vlive/Shop/Parts.php?T=5&NU=15&M=20&Ct=ZA&SbCt=BA_15_20_ZA_50

Ta. The pins are for the 'oles in the fork top cover on earlier bikes. Metal and chrome: proper quality back then! The later bikes use plastic squeeze on caps. The hook end is a bit slim for the recesses on my stanchion cap.

Part 4 in the diagram

http://www.realoem.com/bmw/enUS/showparts?id=0478-USA-10-1988-47E1-BMW-R_100_GS&diagId=31_0373

The actual part is notched 4 ways for a C spanner. This is not shown on the diagram.

The realoem site is getting to be a real pita for ads btw!
 
Is it meant to be done with a castle nut socket?
 
Peter,

Are you sure you're not referring to the steering stem top nut - mine requires a 'C' spanner.

Your 100 GS is the same year as mine and mine has hex threaded caps on the stanchions.

Bob (confused).
 
Peter,

Are you sure you're not referring to the steering stem top nut - mine requires a 'C' spanner.

Your 100 GS is the same year as mine and mine has hex threaded caps on the stanchions.

Bob (confused).


Curiouser and curiouser! I'll take a pic Bob.
 
Voila! That's a 13 mm box sat in the hex cavity. The BMW oem site diagram suggests that the whole cap is a unit but I'm wondering if the outer part acts as a locknut for the inner bit that retains the spring?
 

Attachments

  • image.jpeg
    image.jpeg
    101.5 KB · Views: 180

Attachments

  • bmwhead.jpg
    bmwhead.jpg
    44.5 KB · Views: 140
Well spotted that man! Cheers Gordon. Question now is whether to plough some more cash into those hyper pro springs! :D

Edit: maybe the thread pointed out by Gordon could be made into a sticky? Or moved into the "Common faults etc" sticky section?
 
Are you sure you're not referring to the steering stem top nut - mine requires a 'C' spanner. Bob (confused).

Peter,

Ignore me - my memory is worse than I thought. I had a look at my 100 GS today and its the same as yours DOH :blast.

Bob.
 
It doesn't come itsel' Bob. Part of the reason for the pic was to reassure myself about what I thought the layout was!
 
Well spotted that man! Cheers Gordon. Question now is whether to plough some more cash into those hyper pro springs! :D

Check the site carefully, at one time they had the springs for the HPN inserts which work well with a 450 lb spring on the rear shock, 90mm preload spacer and stock quantity of15 /5 wt fluid in R/C.
Helps if the rear spring is in an Ohlins too!
Never fitted Hyperpro's own set up to an Airhead, but a very expensive set for a VFR made the bike almost unridable on the road, with rider sag less than half of what worked.
 
Never fitted Hyperpro's own set up to an Airhead, but a very expensive set for a VFR made the bike almost unridable on the road, with rider sag less than half of what worked.

Im with beemerbof on this one - I fitted a set of Hyperpro's to my G/S and the spring rate was WAY to high - probably OK if you weigh about 50 stone and have your Paris Dakar tank full 100% of the time, otherwise extremely unpleasant to ride on.
 


Back
Top Bottom