Friends Rebel 250 making strange rattling noise.

[agentbad]

This sound bad to you guys. It just came back from the shop which it just got a basic tune up and now it's making strange noises. 2007 Rebel 250 with close to 40k on the engine. Having a hard time trying to pin down where it's coming from. In person it sounds like something rattling close to the engine but in the video it sounds a bit more like the engine itself.

Link to original page on YouTube.

[Flying]

The video can only be privately viewed.

[agentbad]

Whoops I'll fix that. How about now?

[csmith12]

Hmmm, not a definitive sound to my ear from the vid.

Step one, check oil level and fill/drain as needed!
Step two, lube chain

Tricks to isolate sounds; When does the sound change?

Clutch in
Clutch out
In neutral
In gear
In motion
While stopped
At certain rpm
On the throttle
Off the throttle
With the brakes on
With the brakes off

[agentbad]

It almost sounds like a bolt rattling around inside the engine.

[csmith12]

Ok, hmmmm Is it just me or do you have little to no rattle at idle, ie Only when the throttle comes on?

Check these things too;
Battery cover vibration against the frame
Engine mount bolts

Also, since it seems to be loudest on the right side near the can... I would also vote to check the exhaust for a broken inner layer.

Hillbilly Exhaust Test - lol
Get a piece of heavy rubber (I used a bicycle inner tube) and wrap it around your exhaust can (right side) and then put a large hose clamp on it. Snug it pretty tight but not crazy tight. Start the bike up and give it some throttle, the sound should be drastically lower, if it is.... time for a new exhaust. Oh! don't get it too hot or the rubber may melt.

[csmith12]

Oh! for everyone else...

So you got you some chrome pipes that never turn blue aye? Why? Because they have inner layers that keep the high heat away from the chrome outer. If you get rattles, it very well may be from those inner layers vibrating against each other.

[flitecontrol]

I tend to agree with Chris; sounds like one of the exhaust baffles or possibly the rear bracket hanger is loose. I'd also be concerned about what I didn't hear, which is noisy valves. When the valves on the Rebel are properly adjusted, it sounds a lot like a sewing machine. When the valves get too tight, it's going to cause damage. Honda recommends checking the valve clearance every 4,000 miles.

Tell your friend he's welcome at hondarebelforum.com Lots of knowledgeable folks and helpful information there.