My xs400

So crankcase vent? What's going on with that when I'm going with the pod filters? I'd post pics but I'm on my phone and it's not uploading well...anyways, I've got some parts, speedo, tach, and pod filters from 650direct off mikesxs. I also ordered a sigma 6 1-7 stage jet kit...I've got the manuals from the sticky, haven't studied it quite yet. I'm also going to grab a trailer fender from princess auto and running the sissybar with a big bubble for a passenger seat, anyways!

To the point, anything I need to do these things that I might be missing? My tools r pretty well covered I think at least.
Back to this crankcase vent...what's that? I'm driving a jetta with an aftermarket air filter and there's a tiny filter right beside it, now is that the same thing? And do I need to order another filter? I'm just waiting on the jet kit to come in then I wanna get started...
 
I mean, it's not a vtwin chopper but I'd like the back end to have a very David Mann inspired look to it, but with a sissybar outta this world

So I'm really into the mock up oil tank deal to hold the electricals, now am I gonna have to replace some stuff with different stuff? For lack of better terms...cuz I think I can handle relocating things, cuz I mean, longer wire, different mounting, not so bad, but as for electrical components? I kno the reg/rec needs to be exposed to an air flow of some sort right? And the battery really gotta be upright...I read that the brake light switch is mounted on the airbox and needs to be figured out...anything else I need to consider? And tips? I wanna go with a tube looking oil tank, like a cylinder? Or maybe triangle, I'm going for a compact look, and depending on the frame, I unno really, back to the point, it's the wiring? Anything I need to get?
 
Kingjetpack said:
I'm driving a jetta with an aftermarket air filter and there's a tiny filter right beside it, now is that the same thing?
Click to expand...

Yes.

You can get a tiny filter at most autoparts stores that will fit with some massaging.

Next time don't buy a "jet kit," just buy the jets individually from Mike's.

Kingjetpack said:
the reg/rec needs to be exposed to an air flow of some sort right?
Click to expand...

The rect, yes. The reg, not so much, but certainly not excessive heat. Normally it sits behind the battery and I can't imagine a LOT of air getting to it, but it is also not completely closed in either.
 
Techanacaly the vent is to recirculate exhaust gas from the crank case back into ther carbs as for emission standards.Does it hurt to remove it and replace with one those small filters nope.
 
Does it hurt to vent combustible fumes to the atmosphere? Does it hurt to add an entry point for moisture to the crankcase? Do those filters keep fine dust and dirt out of the crankcase?

There is a reason every engine made in the past 50 some years recirculates the fumes back into the intake. Air pollution is only one factor, the oil vapours in the fumes also help lubricate the carbs, intake valves, and upper cylinders. There is are benefits to keeping the crankcase ventilation system operational.
 
Me as well! And while running those tests, one might as well test all the emissions and weigh the performance difference against the emissions difference. I'm positive that any insignificant change in performance will be greatly overshadowed by the substantial increase in hydrocarbons emissions.

Don't get me wrong, I'm certainly no "environmentalist". But I also don't agree with being a gross polluter when there are better options with little to no drawbacks. And in this case, some positive benefits as previously mentioned.
 
So does anybody have any picture of this system? The modded Ofcourse, with pods and a little filter for the crankcase? No could it be possible to still recirculate that crankcase back into the carbs still with the pod filters?
 
Compared to all the gas guzzling polluting suvs on the road I would hardly think with the small number of our bikes on the road we contribute much to air pollution.Now if you want to see how bad air pollution is go to China where the ranked # as being an air poluter:yikes:
 
Kingjetpack said:
Also, what kind of benefits would be achieved with these pod filters and jet kit, 2-1 exhaust and crankcase vent? In or out of recirculation?
Click to expand...

Minimal benefits until you are near redline; for daily riding you'll likely lose a tiny bit of low-end performance in exchange for that high rpm bump you're unlikely to utilize. I have done all of those mods. Weight reduction makes the biggest difference on a motorcycle this small. I did these mods because aftermarket is cheaper than NOS and I like the way it looks.

Kingjetpack said:
And that little filter for the crankcase vent...that would require cleaning pretty often right? I mean, only guessing cuz it's exhaust right?
Click to expand...

It doesn't require cleaning really. It vents fumes/air when the engine is working properly. If the engine is broken it can start venting some nasty things here.
 
bcware said:
It doesn't require cleaning really. It vents fumes/air when the engine is working properly. If the engine is broken it can start venting some nasty things here.
Click to expand...

Actually, the filter gets dirty and does need cleaning. The fumes and oil vapour attracts lots of dust and dirt. And in temps approaching freezing the filter can ice up. Been there and done that.

All engines, even those in top condition, will still have blowby to deal with. A very good engine's piston rings will leak about 10% when at full operating temp. Most engines are around 30% leakage. More than 40% and the rings are not sealing well and the engine is coming due for an overhaul. Once the vent starts spewing oil, the rings and cylinders are probably well worn.

It is easy to vent the crankcase back into the carbs, even with pods. For SOHC engines, just keep the stock H-pipe and mount the pods to them. For DOHC engines, fabricate 2 stacks for the pods and attach the vent pipe to the stacks. I made my stacks the same length as the factory tubes, 60mm if I remember correctly. Works as well or better than the stock setup.
 
U guys r lots of help, I'm pretty excited to throw these pod filters on! So I just opened up the jet kit, and the jets aren't in pairs...it came with 2 pilots 45, 122.5, 127.5, 132.5, and 137.5 one of each main...needle shims and nylon spacers came with it too and 2 drill bits...do I have everything I need? Cuz I would imagine I would need matching main jets...
 
Some models do have different main jets on each side. I don't know which ones though. Which model do you have exactly?
 
This is my ride
 

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