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Wheel lockup

6K views 5 replies 3 participants last post by  Chip  
#1 ·
I just got a pre-owned 2020 KTM Duke 790 with only 1,600 miles on it 3 days ago and I’m already having trouble with it. So I have only rode it from the grocery store and back 4 times (each trip is a total of 14 miles) and while riding it back home today, my bike kept stalling as soon as I tried to take off from first gear. At first I thought it was me just letting off the clutch too fast but every time I turned the engine back on and slowly let off the clutch, the bike just kept on stalling. So I put it in neutral to roll the back onto the sidewalk and the bike would not even roll when on neutral, since the wheels were locked for some reason. A stranger had to get out of his car and help me lift the bike onto the sidewalk so I ended up having to wait on the sidewalk till the wheels weren’t locked up anymore. I pulled into a nearby parking lot and then stopped at a stop sign, then as soon as I let off the clutch the bike stalled. I kept trying to get it moving but it didn’t move and the wheels were locked. I waited in that parking lot for around 25 minutes before the wheels unlocked and I managed to get it halfway to my house before wheels locked again and I ended up being stuck again for about an hour, until the wheels unlocked again and I was able to bring the bike to my house. I’m not sure why my wheels kept locking when I have ABS on and the bike is still new. I was wondering if anyone has any clue why my bike is acting that way. I’m a new rider so this is all very new to me.
 
#2 ·
Don't think this is a fault of the bike. Possible maintenance or user error. Sounds like your brakes are binding/getting too hot.
Make sure you are not riding with foot on rear brake. Check your brake fluid levels are not too full (up to max mark only). Check that your brake levers are returning fully, aspecially if they are aftermarket.
When the wheels lock, you should be able to feel which brake is binding by trying to push the bike back and forth, otherwise use paddock stands/jack, or tilt bike on side stand carefully.
Brake fluid expands when hot and causes binding if too hot and can't release pressure. Your wait for 25 mins allows it to cool which releases the brakes.
Check the above first, otherwise you have a sticking brake piston which will require a bit more work.
 
#3 ·
Sounds like air in the system to me. I would start by bleeding at both ends and hope all the air is in one caliper or the other (I'd guess it is as it is heat from the discs that causes air o expand and lock the brake). That said, given that it has abs you may have to take it to a dealer or other mechanic that has the equipment to purge air from the abs pump. How it got air in the system is another story -- check to see if the bleeders or brake lines to the calipers are loose.

BTW did you get it from a dealer or private owner? In either case, I'd reach out and ask if any maintenance was done on the brakes.
 
#4 ·
Sounds like air in the system to me. I would start by bleeding at both ends and hope all the air is in one caliper or the other (I'd guess it is as it is heat from the discs that causes air o expand and lock the brake). That said, given that it has abs you may have to take it to a dealer or other mechanic that has the equipment to purge air from the abs pump. How it got air in the system is another story -- check to see if the bleeders or brake lines to the calipers are loose. BTW did you get it from a dealer or private owner? In either case, I'd reach out and ask if any maintenance was done on the brakes.
I got the bike from a dealer. I’ll contact them and ask about any previous maintenance on the brakes. Thank you