brake line - how short is too short?

Put new stainless brake lines on the front of my bike last weekend (Spiegler; 2002 R1150R w/ABS).

Main wheel circuit line (i.e. the long one that feeds a junction block to feed both front calipers) was an inch or so shorter than the OEM hose. I put everything back together, bled the system, everything works - I'm just a bit worried about the hose getting tugged out of the fitting over time, since line is shorter. Anyone else encounter this? Photo shows bike on centerstand. Forks can still go lock-to-lock, but hose is pretty taut. When front wheel is on ground, forks compress a bit. So photo is worst-case scenario.

Can't say that I can tell much difference in braking (I did 100+ miles today), but I'm glad I did the project, based on the way the old hose looked.

Paul

how tight is "taut"?
there needs to be some flex at normal repose, full lock or on c-stand, as you need to accomodate for full extension (like going into a pothole or dip). if you have that you're good. if not, i'd return.

Is that the hose kit provided by Speigler for your bike? In my opinion it is just a bit short. If I were setting up the hose routing I'd have made it about 1" or 2" longer. I have worked on hydraulic hose installtions for 13 years. If the front end on your bike goes to full suspension extension, the hose will be pulled tighter. That in itself is not a problem because a properly crimped hose end will not physically pull out of the hose end.

But when a hydraulic hose is pulled tight, the inner tube of the hose can be pulled agaisnt the somewhat sharp edge of the nipple in the hose end. If this happens enough times the hose end nipple can crack the hose inner tube and cause a leak.

But that will only happen if the front suspension goes to full extension, which is not too likely on the road. You should be okay.

pawork said:

Put new stainless brake lines on the front of my bike last weekend (Spiegler; 2002 R1150R w/ABS).

Main wheel circuit line (i.e. the long one that feeds a junction block to feed both front calipers) was an inch or so shorter than the OEM hose. I put everything back together, bled the system, everything works - I'm just a bit worried about the hose getting tugged out of the fitting over time, since line is shorter. Anyone else encounter this? Photo shows bike on centerstand. Forks can still go lock-to-lock, but hose is pretty taut. When front wheel is on ground, forks compress a bit. So photo is worst-case scenario.

Can't say that I can tell much difference in braking (I did 100+ miles today), but I'm glad I did the project, based on the way the old hose looked.

Paul

Click to expand...

Minimum length should be "at least" the same as the stock BMW line...wouldn't ya think..

I know Spiegler will build to customers specs...

Brake Line Installation

Is that upper banjo in the right position? It looks like it might be on the wrong side of the locating finger.

too short

Thanks for the responses, guys.
The Spiegler kit I got is supposed to be specifically for my bike, and all of the other hoses appear to match OEM length, except the one in question. But this one is definitely shorter, and I think I'll have Spiegler get me one that is the same length as OEM. I'm worried about yanking the hose out of its fitting, whether catastrophically or gradually.

I can understand your concern, and yes the replacement hose should at least match the original hose length so as not to cause these types of concerns.

As far as pulling the hose out of the end fitting; if the hose end is properly crimped to the hose, that won't happen. A properly crimped hose should never pull out of the end fitting before the hose itself fails. But I agree, the replacement hose should match the origianl for length.