Stange noise when riding with passenger

[thewestwood]

Hey all, 
I am a bit of a newbie to the forum and dirt bikes in general, but I do have some knowledge and I've owned a motorcycle all my life. 

But, I have a 250 Djebel (very similar to the DR 250), and there is a strange noise that randomly happens but only when I'm riding with a passenger, cant' seem to figure it out. It's like some sort of clanking (almost like there is something metal bouncing around in the engine or trans somewhere). At first I thought it was the chain bouncing around too much, and it was a bit loose, so I tightened to the right specs. Still nothing. It happens when I'm in like 4th or 5th gear cruising pretty steady usually. Any advice here at all would be amazing. Thanks guys.  

[Pittbull]

Most likely just nagging from your passenger, tell her to get her own damn bike and the noise should go away!

[MCVL]

Hi! I'm a newbie too, but Djebel was Japan only and is more like DR-Z 250, the dr250s had Single Camshaft, the dr250r stayed in Japan, and dr-z250 was a dr250r for USA as I remember  ?

There is a whole club dedicated to Djebels in Russia, they travel from one side of Russia to another on them and sometimes to Mongolia =)

Proven to be a most reliable bikes out of air cooled 250cc

As for a noise it's probably a 250cc engine screaming becouse of overload ) How much do you two weight?

[thewestwood]

Thanks for the info MCVL, I had an idea from my research that the Djebel was only out here in Asia (living in Cambodia at the moment), I weigh about 180 lb, and with the average passenger (about 140 I'd guess) that'd be like 320lb or so. If that is the case - the engine screaming, what would it sound like?? The sound it's making is really specific and is kind of a 'clanking' (almost like something is smacking around a little bit), do you think it's something I should be seriously worried about when taking a passenger? thanks again for the help

[Mike38]

Not sure if this will help you much, but I have noticed my DR650 sounds different when I have a passenger. Not a knocking or clanging sound, just different. My guess is the normal sounds from the bike are being redirected somehow and I’m hearing things that I normally don’t when one up riding.

 

Is your tire pressure okay? There is a sticker on the swing arm of my DR650 with suggested tire air pressures for one up and two up riding. I think it’s something like an additional 4 or 5 psi for two up. You may be hearing a howl from the tires.

 

Also, recheck that drive chain. You may want it a bit on the looser side with the extra weight. The suspension will be a little more compressed and you would want a little bit looser chain then you would one up riding.

 

[thewestwood]

Thanks for the reply Mike38, I'm reallyyy sure that it's nothing to do with the tires, but thanks for the suggestion. It's a really distinct sound and only comes pretty randomly (and kinda loudly too), while cruising at a steady pace. I have no idea but it obviously has to do with the extra weight. 

I had the chain looked at by a pro here, and for some really weird reason it actually get's looser as it goes down (even the guy looking at it from the bike shop was stumped), but he thinks it may have to do with a modification to the rear suspension from a previous owner - so yea weird, it actually gets a bit looser as it goes lower and tightens as it sits freely... weird, I know.

It sounds like it's coming from the front sprocket (general area) so not sure - it could be something in the tranny, sprocket, engine, not sure...

[gimped up]

Thanks for the reply Mike38, I'm reallyyy sure that it's nothing to do with the tires, but thanks for the suggestion. It's a really distinct sound and only comes pretty randomly (and kinda loudly too), while cruising at a steady pace. I have no idea but it obviously has to do with the extra weight.

I had the chain looked at by a pro here, and for some really weird reason it actually get's looser as it goes down (even the guy looking at it from the bike shop was stumped), but he thinks it may have to do with a modification to the rear suspension from a previous owner - so yea weird, it actually gets a bit looser as it goes lower and tightens as it sits freely... weird, I know.

It sounds like it's coming from the front sprocket (general area) so not sure - it could be something in the tranny, sprocket, engine, not sure...

Make sure the sprocket isn't rounding off the splines.

[thewestwood]

Ahh so maybe the extra weight could be causing the sprocket to strip the splines a bit?? That'd be bad but maybe could explain the sound, is there a way to tell when the bike is stationary?? just looking at the splines I guess. And if it is the case is there something to do to further prevent it or just a new drive shaft! (or maybe just new sprocket)? Sorry if I'm messing up the terminology here I'm a bit of a newbie like I said haha. 

[gimped up]

Check it with bike in gear just rotate it to see if it has play on the shaft. A new front sprocket will prolong it. Depending on how bad it is.

[gimped up]

You can look up this same problem in the Honda xr650 specific forum. They were bad for it too. But there is in depth posts on this there.

[thewestwood]

Cool thanks ridngslikecrack. I will look into all of this, hopefully it's not too bad! We'll see, I'm out in the middle of Cambodia so maybe worst case scenario a new sprocket and a tack weld might do the trick ?

[William1]

Chances are, the bike is bottoming and the chain is rubbing on the roller (if it has any), Guide (if it has them) or frame /swingarm.

 

I doubt your bike is sprung for two up riding. A bike that size it typically spring for a 150 pound rider.

[thewestwood]

Ok so just an update, I went for a cruise with a passenger today. I seems to actually be only doing this noise in 4th and 5th gear, didn't hear it at all in 1,2 or 3. Not sure what that means but makes me think it has something to do with the tranny or clutch. But again not positive... why would the extra weight cause a random clanking noise only in 4 or 5th gear? Anyways thanks for all the help here guys appreciate the feedback

[pre-mixed]

I would guess that with two people you are compressing the suspension Enough to loosen the chain and you are hearing the chain slap on its rub block. Assuming that it really is getting looser as it compresses like you said. The chain slapping and making noise usually happens when you are just cruising along without bein under a large load