Final drive breather

garnotte

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I just cross this(1 to 2 foot of water) and I found a lot of water in the final drive.

I run the hose along the swing-arm and up under the seat. I didn't but anything on the end, it can't be worst than the original breather.
 

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EricV

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garnotte said:
I just cross this(1 to 2 foot of water) and I found a lot of water in the final drive.

I run the hose along the swing-arm and up under the seat. I didn't but anything on the end, it can't be worst than the original breather.
Thanks. ::008::
 

limey

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I've ridden in a lot of water and never had a problem.
 

GrahamD

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Never had a problem either, but I would suggest if you like turning up at icy water crossings with a smoking hot diff and sitting in the water for some Buddhist monk training you do install a breather.

You can always stop, walk the crossing, let things cool off and save you, the bike and the FD a potential problem.
 

greg the pole

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I think this is a non issue.

After quite a few water crossings with mine, the only issue came up is when I found my rear main bearing seal leaking at 36km.
The culprit was the inner rubber plug on the right side of the swing arm that fell out. Yamaha never secured it properly, allowing water to come into the swing arm, and collecting at the lowest spot near the shaft seal.

yes a bit of it came out through the drain hole, but quite a bit of it collected with the dust, and turned to a fine paste, eventually getting past the seal.

If you're worried about this, change your diff oil at every oil change, and see what's in there...
http://thetenerist.wordpress.com/2013/09/24/rear-shaft-drive-seal-replacement-and-staintune-pipe/
 

Don in Lodi

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GrahamD said:
Never had a problem either, but I would suggest if you like turning up at icy water crossings with a smoking hot diff and sitting in the water for some Buddhist monk training you do install a breather.

You can always stop, walk the crossing, let things cool off and save you, the bike and the FD a potential problem.
::008:: Same story with boat trailer bearings, dunk a hot hub in the lake and the previously heat-expanded air condenses and pulls a measurable vacuum and will pull water in past the seal. Thus Bearing Buddy, a spring loaded dust cap that keeps a positive pressure, even with the expansion-contraction thing. Remote venting works, just about every automotive differential has 'em, especially 4x4's. I'd recommend a small filter for it though, remember, it does breath.
 
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For this issues, I always re-grease front and rear wheel bearings, bearings for the rear suspension relay and bones, swing arm bearings. I had done this for other bikes, and I had seen that those bearings come kind of dry. For the ST the job with the swing arm bearings is kind of a pain, many retainers and many seals, too many screws, due to the driveshaft.

Besides, I always put a greaser bit on the steering bearing shaft, to keep those oily.

Where I live many times one has to cross water many times, even in the cities. It rains like hell, and bikes are often cleaned and whashed with high pressure. Rain and high pressure water, are both enemies of seals and bearings.

Juan Valderrama
XT1200Z
Broadcasting from Bogotá - Colombia.
 

nimac

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Waking up an old post with my take on the Final Drive breather mod.
After getting leaking seals front and side from a blocked breather hole due to many kms of red desert dust and years of crusty gravel roads, I decided to install a remote breather up under the seat.
Using 4mm hard tough PE pressure line and push in fittings it was surprisingly easy.
Parts list: 1 x1/8" BSP right angle and a 1 x 1/8" BSP 4mm straight push in fittings, 2m of line to suit the fittings, and maybe a thread tap to suit as well, but you could probably just force the fittings in the right size hole as it is kinda thin gauge metal and cable ties.
Getting the old breather out was a pain, the top cap screwed off in no time, so that left a conical stub that is difficult to grip, but I managed to get it out without distorting it. Upon inspection, it was confirmed that the tiny little pin hole in the stub post body was blocked and that was why both seals let go together.
So I carefully bored a hole over the same area of the original pin hole consuming it with the new bigger hole to accommodate the new 90 degree hose fitting, threaded it, and gently screwed it into place.
I used the cap that was twisted off as the upper cup with oiled foam in it retained by a wire pin and the straight hose fitting installed into the bottom of it.
Routed the pipe as you can see in pics, with a small hole drilled into one of the fins on the FD to use a cable tie.
Under the seat is about as high as the air box intake, so if water gets that high, I will have other things to worry about I reckon!
Now I can forget about any dust blockages and water ingress, one less to worry about in the middle of nowhere and a long way from home.
Oh, and I used clear pipe only because I couldn't get black at the time, but I will replace it with black when I find some so it will hardly be noticeable, so easy with push in fittings!
 

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