JJB350
New Member
Hey everyone,
I have a Nighthawk 250 rattle/buzz that I'm having a hard time diagnosing. Here's the info:
1993 Nighthawk 250, 28,000 miles, owned for 5 years
Has been modified, after being rear ended while stopped (the end of the frame was bent so I chopped it off, added a hoop, custom seat, got a different tank.) After finishing the mod, I brought it to a shop to have the clutch plates replaced, as the clutch was starting to slip. I also had them replace the chain and sprockets, which needed to be done.
When I got it back, I noticed a rattle from the exhaust--this was just a worn gasket where they mount on the frame. I replaced that and while riding noticed a rattle coming from the left side of the engine, as best as I can tell. This is the rattle I'm unsure about.
It only happens in a specific window, when I'm at a mid-low rpm. I tried suspending the bike to get rear tire off the ground and run through the gears (is that bad?) but there was no rattle then. I checked the valves--only one was slightly off, which I adjusted. Could something with how the guys at the shop did the chain/sprockets have caused this?
I have also read it could be the cam chain, or perhaps part of the system? When do these parts usually go bad? I have not checked them and don't know if they have been checked/replaced. Is there a way to check without having to remove and disassemble the engine?
The video below has the bike idling so you can see it. Then it is audio only, that I got while riding. I have "rattle/buzz" text appear on screen when the sound I am talking about is most prominent.
I'd like to get some input before thinking I need to take the engine apart (which I've never done) or pay someone else to.
I have a Nighthawk 250 rattle/buzz that I'm having a hard time diagnosing. Here's the info:
1993 Nighthawk 250, 28,000 miles, owned for 5 years
Has been modified, after being rear ended while stopped (the end of the frame was bent so I chopped it off, added a hoop, custom seat, got a different tank.) After finishing the mod, I brought it to a shop to have the clutch plates replaced, as the clutch was starting to slip. I also had them replace the chain and sprockets, which needed to be done.
When I got it back, I noticed a rattle from the exhaust--this was just a worn gasket where they mount on the frame. I replaced that and while riding noticed a rattle coming from the left side of the engine, as best as I can tell. This is the rattle I'm unsure about.
It only happens in a specific window, when I'm at a mid-low rpm. I tried suspending the bike to get rear tire off the ground and run through the gears (is that bad?) but there was no rattle then. I checked the valves--only one was slightly off, which I adjusted. Could something with how the guys at the shop did the chain/sprockets have caused this?
I have also read it could be the cam chain, or perhaps part of the system? When do these parts usually go bad? I have not checked them and don't know if they have been checked/replaced. Is there a way to check without having to remove and disassemble the engine?
The video below has the bike idling so you can see it. Then it is audio only, that I got while riding. I have "rattle/buzz" text appear on screen when the sound I am talking about is most prominent.
I'd like to get some input before thinking I need to take the engine apart (which I've never done) or pay someone else to.
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