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Discussion Starter · #1 ·
Hey there, after i replaced some seal in my front fork and reinstalled everything, the forward brake goes really heavy.
and when ABS is selected OFF it brakes like it normally should.
The ABS pick up on the front wheel is installed the same way it was.
is there some sort of adjustment for it? or is there any other way to solve the issue?
 

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Welcome Nick,

It is not clear to me what is going heavy?
The lever at the bars? The pads in- out?
Have you had the brake pads out of the calliper?
Where did you hang the calliper when the forks were out of the triple clamps?
 

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Discussion Starter · #3 ·
It's indeed the brake lever that goes heavy, until your'e almost at full stop, than it physicly gets softer and the lever goes smooth like it should, also the speed reduction while braking is dangerously low.
the porblem disappears when ABS is selected OFF, then the lever and the actual brakes are working normally.

I hanged the caliper with some tyraps on the handlebar, already bleeded air from it to be sure, but that didnt make any difference, further i didnt change anything on the caliper or pads.
 

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I don't know why it is in the manual but after doing it at few times, I never remove the abs sensor or the fender when removing/ reinstalling front wheel. Just be careful making sure everything is lined up-never did it on 625 SMC either? Also on the tank removal I only remove the three mounting bolts and the two bolts that connect shroud to frame leaving the shrouds on the tank since I no longer have cannister or coolant recovery tank.
 

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seems like the abs somehow is kind of turned on constantly. At first check if the abs sensor has the right distance from disk brake and it is well tighten. If yes, try to start the engine without the abs sensor wire connected and connect it while engine is operating. If this won't fix it you must go to the dealer for further examination.

Sent from my A80Pro using Tapatalk
 

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Sorry to reboot a dead thread.

I am having the same issue after fixing the fork seals on my 2018.

I did everything according to the instructions in the repair manual from KTM. Once I got the bike back together I took it for a test ride and below 5ish mph the brake lever works just fine, but above 5 mph it gives me about 50% braking and the lever is very stiff. Then, once I get below 5 mph or so the lever loosens again and the brakes return to full force.

I think that the ABS module is constantly active above 5 mph and that is interfering when I pull the lever. I have disconnected the ABS sensor and plugged it back in after starting the bike, as well as disconnected the ABS module then plugging it in after starting the bike. Same issue. I bled the brakes several times using brand new fluid and even zip-tied the lever down for about 24 hours. Same issue. There is no way to adjust the positioning of the ABS sensor, and the speedo works just fine, so I think the sensor is good still.

The brakes work just fine (100% power) if I circumvent the ABS system either mechanically or by turning it off in the dash.

I really don't want to replace the ABS module because there was no issue with it before I replaced the fork seals and I did nothing to it to cause an issue. I am really hoping that somebody can tell me how they fixed this issue for sure.
 

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It confirms that the issue is with the ABS, which was already quite conclusive. Given you didn’t have the issue before, the ABS sensor is the only part of that system which could have been damaged in fork removal.
 
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