|02-01-2014, 08:16 AM||#1|
Joined: Jun 2008
Location: Cluj, Romania
AluFlange - protection for the R1200 rear wheel flange
I have started to make these protections for the R1200 series. They fit on the outside of the aluminum flange, making it more robust and less prone to cracking. Google has a lot of search results for "rear wheel flange crack"
So, the R1200 series, RT, GS, R, etc. have this aluminum flange that connects the rear wheel and the brake disc to the hub. This part is known to crack, so BMW made an upgraded flange, made out of a steel.
Indeed, the new one is better than the aluminum one, but it has one big disadvantage - it is ~ 2/3 wide. This means that the rear wheel and the disc can develop play, in respect to the spline'd hub. Since it is narrower, it also has a spacer ring to compensate that extra width. This is bad, since with the new upgraded flange, the spline contact surface decreased.
There's another reason that the upgraded flange is not fit for this application. The material that it is made of is now hard, and it can destroy the splines on the hub. That is why first, they made it out of Aluminum, so that the flange would wear first, since it would be more easy to replace.
So, the protection I make, is also made out of Aluminum, 7075. This is a hard alloy, used in making auto parts mostly. The protection is precised cut on a CNC and then anodized, for a good, long, corrosion protection.
Installing it is pretty easy. First thing, put the bike on the center stand and take off the rear wheel.
You now have to clean really good the outside of the flange, cannot allow any dirt to get in there. I am using an old toothbrush and some brake cleaner for this, because I don't have to rub that much.
After you are sure you cleaned everything well in there, you can start to put in the protection. Hover it over the flange and then, using a rubber mallet, gently tap on the outer side of the flange, going round, little by little. Heating the AluFlange prior to installing does not hurt. It will only make your job easier.
If you do not have a rubber mallet, you can use a metal hammer, but DO NOT hit the protection using the metal side! Use a piece of soft wood, in order to not destroy the finnish on the protection.
Go round and round until the AluFlange protection rests on the brake rotor. You can then put in the 5 pins provided. Tighten them in by hand until they start to get to the other side. Then mount the rear and check the gap between the pins and the wheel hub. Then take off the wheel and un-do the pins, until they would almost touch the wheel hub. Then use the nylon nuts and secure the pins.
When installing the wheel, make sure NONE on the pins touch the wheel hub. They should be near the wheel center hub, but not touching it. Their purpose there is as safety, in case the protections tends to com off the flange (it won't, but it's OK to be safe).
Then you can mount the rear wheel, tighten the bolts to specs (check the manual for that torque) and spin the wheel by hand, make sure all is in place. Then take the bike for a round.
Like I said, the AluFlange is made out of 7075 anodized aluminum. It is very strong and light(~190 grams w/ screws and nylon nuts). It's worth keeping the OEM aluminum flange on the bike, as long as you have this protection on.
The price for one AluFlange is 135$ (USD), shipping included, worldwide. I also have a version for the GSA spoke wheel.
So this is a 135$ part that saves a ~400$ part. You do the math if it's worth buying it or not. Not to say that it can keep you from being stranded in the middle of a trip.
Orders can be processed trough my webstore HERE.
|02-26-2014, 04:36 AM||#2|
Joined: Apr 2010
Managed to install the part quite easily following Dan`s instructions.
The aluminium flange is very lightweight and doesn`t have any kind of negative effect.
After having a fellow gs`er who faced this problem, I'm so glad I taken care of the flange crack issue
|Thread Tools||Search this Thread|