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Discussion Starter #1 (Edited)
Jerk/Surge? when decelerating in 1-2 gear

This has just recently started to happen a few days ago, when coming to a stop it like jerk/surge a few times. Any ideas on what this could possibly be?

Ok so I uploaded a better video which shows it surging/jerking a lot better

(Fixed) Front sprocket nut was loose creating movement in the front sprocket area

https://streamable.com/bmxwq

Better video below:
https://streamable.com/yoyyl
 

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Discussion Starter #6
Clutch issue?
I've adjusted the clutch and still no luck. Kinda feels like a clutch/chain issue when it happens(atleast I think). Rear sprocket is good, gotta check the front tomorrow. Do you know if its possible for the gears to go bad and it only is one or does that not sound like the case?
 

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On the gears, if the teeth on one of the gears was somehow damaged you'd have the issue accelerating and decelerating, and if maybe the dogs were damaged the slip when they disengaged and engaged again would be (from what I can tell from the video) a lot more violent and probably something you could hear.

the_gooch is probably on the right track with it being a clutch issue, though I'm guessing he's talking about worn clutch plates? It's a little bit hard to tell in the video, does the engine speed change with the jerk? Any tight spots in the chain? Wheels rotate relatively freely/smoothly with the bike on stands? I know it's harder to test this, but is there any semblance of this issue in the higher gears?
 

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RPM looks to stay steady but sounds and looks like loss of power to final drive. I would look at the basket, springs and plates.
 

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I've adjusted the clutch and still no luck. Kinda feels like a clutch/chain issue when it happens(atleast I think). Rear sprocket is good, gotta check the front tomorrow. Do you know if its possible for the gears to go bad and it only is one or does that not sound like the case?
There was a selector shaft issue but the bike would slip out of gear. I would open up the clutch cover and pull the clutch out.
 

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Discussion Starter #11
On the gears, if the teeth on one of the gears was somehow damaged you'd have the issue accelerating and decelerating, and if maybe the dogs were damaged the slip when they disengaged and engaged again would be (from what I can tell from the video) a lot more violent and probably something you could hear.

the_gooch is probably on the right track with it being a clutch issue, though I'm guessing he's talking about worn clutch plates? It's a little bit hard to tell in the video, does the engine speed change with the jerk? Any tight spots in the chain? Wheels rotate relatively freely/smoothly with the bike on stands? I know it's harder to test this, but is there any semblance of this issue in the higher gears?
In higher gears no problem at all. And on the stand it has no problems
On second thought, have you checked with a GS911 for any codes being thrown first??
No codes, I just checked the front sprocket and I was able to twist the nut off with my hand... I don't think I was suppose to be able to do that, I just torqued it down to the required spec and I will let you know if the problem is still there.
 

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Discussion Starter #13
Shouldn't be that loose! You still have lock washer bent over nut?
Yes the washer is there, also it didn't fix it. I wanna say I feel like a pulsation from (clutch/chain) when that happens. What would my best bet be pull the clutch out?
 

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Type of riding? Hard street riding? Commute to work? Track?

I was thinking this may not be the clutch or chain. More like a air box/idle or fueling issue. Maybe carbon on the back of your valves. It seems to hang in the revs and surge up and down. Then settles. Only happen on deceleration? All gears? Certain rpm range? Any changes to the bike prior to this happening?
 

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Discussion Starter #17
Type of riding? Hard street riding? Commute to work? Track?

I was thinking this may not be the clutch or chain. More like a air box/idle or fueling issue. Maybe carbon on the back of your valves. It seems to hang in the revs and surge up and down. Then settles. Only happen on deceleration? All gears? Certain rpm range? Any changes to the bike prior to this happening?
Type of riding: Hard street riding/cruising

Yes it only jerks like this on deceleration when slowing down after 60-70mph seems to only happen in first gear. I didn't pay much attention to the RPM range when its happening but I do think its around the same speed each time. Only change I did was add a fuel cleaner.

I just drained the oil its dirty and I also have metal shavings in it, should I be concerned? https://imgur.com/sAv7A8u
 

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Type of riding: Hard street riding/cruising

Yes it only jerks like this on deceleration when slowing down after 60-70mph seems to only happen in first gear. I didn't pay much attention to the RPM range when its happening but I do think its around the same speed each time. Only change I did was add a fuel cleaner.

I just drained the oil its dirty and I also have metal shavings in it, should I be concerned? https://imgur.com/sAv7A8u
Make any progress on this issue?
 
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