2021 Defender Knocking and stalling

[DEFENDERGUY14]

Just purchased my 2021 can am defender HD10xt. Brought it home and put 77 kms on it. Was out for a small cruise on a plowed road. Got the bike up to 95kmh slowed down for a corner then tried to speed up again. While trying to speed up the bike chugged almost like a misfire. I let out of the throttle, went to get back into it and it wouldn’t let me. I pulled over and the bike stalled. Fired it up and there was a loud rattle/knock from the motor area. Shut the bike down and went and go get my truck and trailer. Fired it up to try and load it and it stalled 5 times finally got it to run long enough to get it up the Ramps. Drove it out and dropped it off at the dealer. They started it and it knocked and stalled a few times for them then stopped. Magically the issue has stopped and it operates fine. They tore into the clutches, magneto and the valve covers hoping to find something with zero luck. 
 

I’m trying not to loose sleep over this but it does not sit well with me. What would cause the bike to act like this? 
 

no lights on the dash or messages. Whatever was causing it would load the motor up enough to stall. With the dealer not being able to give me a solid answer on the bikes issue I don’t feel comfortable taking it on an all day ride and it potentially leaving me stranded in the bush. 
 

any input or ideas will be greatly appreciated. 
 

Thanks 

[Andystoy19]

My SWAG might include a look at the VSS, engine speed sensor and the fuel pump pressure? Did the dealer recover any codes?

Good luck.🤔

[DEFENDERGUY14]

No codes recovered

[RadioguyJ]

What fuel are you running?  Perhaps it’s contaminated?

[DEFENDERGUY14]

Running 91, brp has come back and said only to run 87 and that’s what was causing the motor to run rough and knock. Getting the bike back tomorrow and will test it and see how it works. Fingers crossed 

[RadioguyJ]

My dealer told me the same thing.  87 only, which has a 10% ethanol blend here in Minnesota.  It’s going to be different for me to run ethanol in this.....my toys only get 91 non-oxygenated gas.  

[Steelslinger]

On 1/21/2021 at 10:42 PM, RadioguyJ said:

My dealer told me the same thing.  87 only, which has a 10% ethanol blend here in Minnesota.  It’s going to be different for me to run ethanol in this.....my toys only get 91 non-oxygenated gas.  

Anything Fuel Injected nowadays is going to be set to run 87 octane from factory. Re-programming and performance mods with advanced timing or high compression would be needed to run anything higher without issues.

[DEFENDERGUY14]

Got the bike back. Still knocking. 

only seems to do it coming off of wide open throttle then slowing to a stop. Knock only happens at idle and doesn't get worse with RPM. if I let the bike sit and idle it will eventually idle down and stall. Seems to go away when revving the bike up but comes back at idle. Taking it to another dealer this Sunday to let them have a look. Definitely not impressed with this bike or the responses from brp 

 

[RadioguyJ]

That sounds terrible.  I hope you can get to the bottom of it!

[Bad Daddy]

Almost sounds like something flailing around in the CVT, or under the valve cover. 
Let us know what they find...

[supersix]

On 1/25/2021 at 10:48 PM, DEFENDERGUY14 said:

Got the bike back. Still knocking. 

Not good at all.  Please keep us in the loop and let us know how it turns out. 

[Andystoy19]

If the dealer hasn't had the CVT cover off it may be something he wants to check, it could be a broken button in the secondary or a broken spring that doesn't release the belt properly but that is something the dealer may have checked??? JMO🤔

[XmrOkie]

On 1/25/2021 at 10:48 PM, DEFENDERGUY14 said:

Got the bike back. Still knocking. 

only seems to do it coming off of wide open throttle then slowing to a stop. Knock only happens at idle and doesn't get worse with RPM. if I let the bike sit and idle it will eventually idle down and stall. Seems to go away when revving the bike up but comes back at idle. Taking it to another dealer this Sunday to let them have a look. Definitely not impressed with this bike or the responses from brp 

 

Evenin folks. I’m new here. I just had this happen to my rig tonight and googled the noise and what happened and it led me here. Just curious if the situation had been fixed. Thanks. 

[rschuch]

Has this issue been resolved? I have a similar issue. Also a 2021 Defender HD10 XT.

Mine is at the dealer for the second time now. They replaced the fuel pump the first time, didn't fix it. They now are thinking maybe it's the primary clutch. Parts are on back order until the first of September.

Edited August 18, 2021 by rschuch
Wanted to add more.

[DEFENDERGUY14]

So to follow up with everyone, took the defender to another dealership. They tore the motor down and found metal fragments on top of both pistons. The believe they were left inside of the throttle body and got sucked into the motor. Couldn’t get me a new motor so they rebuilt it from crank up. Zero issues now. BRP also gave me an extra years warranty as compensation. 

both pistons and heads were severely damaged. Took 2+ months to get it back up and running. 700ish kms later and hasn’t skipped a beat.