2nd gear

Hello everybody, this is my first post here,

Now to the problem, i got a xr400 from 99 and i'm loving the bike, but in 2nd gear on low to mid rpm there's like a whistling sound (hard for me to explain in english) but i think kind of like a broken ball bearing sounds. also on low rpm the noise is quite loud.

If someone please can give me advise what to do.

would you say it happens when the bikes under strain, like goin up a hill or accelarating fast? coz this would say main bearings to me.

No it's not just when the bike is under strain, even when i'm de-accelerating (hmm wrong word maybe) on low to mid rpm, but only 2nd gear!

Can i keep riding? or must i do something about it right away do you think?

Just curious, how's your engine oil level?

I was out now riding around in the snow for about 15 min, and then checked the oil level. and it's on the Upper mark.

anyways this time i noticed that the sound (noise) disapered when i let of the gas. and i rode without a helmet so i could listen better :thumbsup: and it's difficult to locate where exactly it comes from, but it's maybe from the lower part of the engine.

it may just be the chain rolling around the front sprocket. In second gear you would be going slow enough so you can hear it, yet fast enough for it to make a noise. A good test would be to find a hill, leave it in neutral with the engine off and roll down it at that speed and see if thats the noise your hearing. Otherwise you might have something more serious.


I got the chain noise, but it doesnt bother me much, this noise comes from somewhere inside the engine/transmission, it's sounds almost like yer playing a note on a intrument, like an old synthesizer or something and it's pitching up as you accelerate. hmm.. maybe a could sample it and use it in my music :thumbsup:

:thumbsup: but i just bought this bike, and i'm not to happy about it. *sigh*

Does it idle ok? if not a badly leaknig head gasket will whistle loudly and the bike will not idle. worse case is that the crank bearings are shot...

Well - here's a long shot. My 01 XR 400 started making a humming, buzzing sound last season that I had difficulty pinning down. After riding on some fire roads and paying close attention I figured out where the annoying buzz / humm / whining was coming from - none other than the bottom chain roller, just behind the front sprocket. That particular roller does not utilize a bearing and is literally a piece of rubber spinning on a metal mount...it was making all kinds of wierd noises. I replaced it with an aftermarket chain roller that uses sealed bearings and that eliminated the problem. Again, it's a longshot, but I thought I would mention it.

Cheak every chain thing you can because what i am about to suggest is gonna be alot of work and you don't want it to be for nothing.

If you are absolutly possitive that it is comming from somewhere inside the engine/trans then start pulling off the right and left side covers. Pull the clutch. With that removed you should be able to see some of the bearings. Is none look bad from there, you might need to spit the cases. This is gonna be alot of work and you might cost you money even if you don't find anything (I.E. gaskets).

your not going to like this,but you are describing the exact same thing i went through before i split the cases and replaced 2nd gear. mine quit making noise for about 30 seconds just b4 i lost 2nd alltogether. oh 1997 xr400r

thank you for all the replies, i talked to a mechanic today and that problem wasn't news for him, he said i have to change the 2nd gear as soon as possible, or it will be more expensive in the end :bonk: he said with just a minor wear on the gear it self (sprocket or whats it called) will make such a sound, and it will get only worse if i wait.

Sadly this mechanic doesn't want to take on my Honda..." i only do Husqvarna" he said :thumbsup: however i'll check everything you guy's said, before i split the cases :thumbsup:

hehe i like the spellcheck, it didn't like my spelling on "husqvarna" it suggested "Hussein" instead :bonk::bonk:

yeah 2nd gear and the the gear fork too maybe have to be repalced :thumbsup:

...i had the same thing on my MTX200R...the gear "dogs" were worn...this made the fork work harder and that also got screwed...

my mechanic got it wrong and only replaced the gear fork and not the wheel...worked fine for 3-4 days and went back to the same problem...

when we opened'er up...the new fork was also worn....

finally he replaced the wheel and the fork...all's fine :thumbsup:

This is what my bike looks like right now.

well it will be as good as new when i'm finished, (i hope)

edit: new try


This is what my bike looks like right now.

well it will be as good as new when i'm finished, (i hope)


Linky no worky.


does the link work now? :thumbsup::thumbsup:

does the link work now? :thumbsup::thumbsup:

Yes, except there's no bike in the picture only a bunch of random parts :bonk:

allright, this is what the 2nd gear on my xr4 actually looks like, not to nice huh :thumbsup:edd6a7e04e7f4dd932a5c44f282f9b4e.jpg

How about the rest of them? Your pic looks like the product of tight woods riding.

allright, this is what the 2nd gear on my xr4 actually looks like, not to nice huh :thumbsup:edd6a7e04e7f4dd932a5c44f282f9b4e.jpg

Yow, that looks like crap! Bad oilchanges?

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