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littlebill31
Smells of Raw Fuel
If you are talking about the oil breather on the back of the head, it's to let the pressure out. If the engine was totally sealed there would be no release for the air pressure made by the pistons moving. It also releases aerosolized oil, resuculating it back through the carbs as a type of emissions/ "don't want it spraying on the rear tire" feature.
There should be a tube coming from it. I use a power brake check valve. You can search it on here.
There should be a tube coming from it. I use a power brake check valve. You can search it on here.
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littlebill31
Smells of Raw Fuel
The purpose of using something as the check valve, is to let aerosolized oil and pressure out without letting dirt and shit in. If you don't have a breather filter, or at least a length of tube, then all that road grit is going right into the engine. The pressure goes out, then a little air in. It breathes.
poorman9
XS650 Addict
Not to steal this thread, but I've been wondering the same thing.
Here's what my breather hole looks like
I do notice a lot of oil getting prayed all over down there. What should I do?
Here's what my breather hole looks like
I do notice a lot of oil getting prayed all over down there. What should I do?
littlebill31
Smells of Raw Fuel
Well, that is broken. There should be a "Y" type "pipe" coming from that hole.
glennpd
4 bikes, 4 dogs, 1 wife
TeeCat
One-Mik Wonder
Glenn, someone on here may have a replacement for you. Barring that option, or as a stopgap, you may be able to (after removing the breather from the head) tap some threads in the existing hole, and then install a barb. (Ofentimes one of the "Y" nipples is capped anyway). Then you can affix a correspondingly sized rubber hose with a "Help" one-way brake booster valve near the other end of the hose, with a small breather cone filter (available at your local auto store) to catch any exhaled mist.
TC
TC
littlebill31
Smells of Raw Fuel
I can't post a pic as I am on my phone. But search and read the thread entitled, "Mike's PCV valve". It shows what it looks like.
They break easily. I have about 4 that are all broken. Check the classifieds on here or ebay.
They break easily. I have about 4 that are all broken. Check the classifieds on here or ebay.
TeeCat
One-Mik Wonder
Dakota_Lew
XS650 Agronomist
littlebill31
Smells of Raw Fuel
I use the "STOP" brand power brake check valve. Costs a couple bucks. The Mike's, I have been told, has a ball bearing in it or something and doesn't work well.
I just ran a length of hose from the breather to the valve. Then have is positioned above the pod filter in order to let the weeping oil catch in it.
I just ran a length of hose from the breather to the valve. Then have is positioned above the pod filter in order to let the weeping oil catch in it.
TeeCat
One-Mik Wonder
The Mike's one - if it's the one you're referring to (and the one I posted a link to) - uses a directional reed. I think it was twins who has warned against using the ball bearing-type automotive PCV valves, as the ball bearing cannot react to the engine pulses quickly enough to have the desired effect. But the Help and Stop ones are reported to be effective, as they use a directional flap.
TC
TC
littlebill31
Smells of Raw Fuel
Ya, one of them has a ball bearing, which cannot function properly. The "Help" is the one I have. I can't remember anymore, lol.
Thanks guys. That was fast. Should autozone have that Help part? Im looking over my whole bike to see if I'm missing something (like the advance mech) that might be causing me to have less power than I'm supposed to. 75-80mph feels like I'm hurting it. I saw that list pamcopete had that could be reasons why I have less power and I have fixed most of them. I'm just waiting on my new brake switch so I can ride it again. The freeway is not fun...
Posted via Mobile
Posted via Mobile
littlebill31
Smells of Raw Fuel
I got mine at one of those places. Autozone, advance auto.
If you're doing 80 on your bike, that's good. These are not speed demons. Changing you rear sprpocket will ad some top end, but you will lose a little take-off.
If you're doing 80 on your bike, that's good. These are not speed demons. Changing you rear sprpocket will ad some top end, but you will lose a little take-off.
Oh ok. I just feel like it's winding out a lot. All these other people keep saying they can get 100 pretty easy. I'll just stay off the freeway with this. 75 is too slow for the slow lane sometimes out here...
Posted via Mobile
Posted via Mobile
Hairyblackdude
XS650 Addict
I had my breather open when I was riding for a few hours this last weekend.. Just finished the bike & I didnt do anything with it yet..
When I got back, I noticed some slight oil residue on the engine & the backbone near the carbs..
I slipped a tube over the nipple & ran it down between the carbs & behind the engine..
I was gonna install a small breather filter right on it, but I was afraid it would just get saturated with oil & eventually start dripping...
When I got back, I noticed some slight oil residue on the engine & the backbone near the carbs..
I slipped a tube over the nipple & ran it down between the carbs & behind the engine..
I was gonna install a small breather filter right on it, but I was afraid it would just get saturated with oil & eventually start dripping...
TeeCat
One-Mik Wonder
It will. When that happens, or before, change the filter. They just vented the crankcase to atmosphere like that on the early bikes, but better to have a little cone filter catch the oil mist than have it on your rear tire.
TC
Hairyblackdude
XS650 Addict
Haha, ya know? I didnt even think of that !!
Im gonna have to put like a 4 foot hose on there & just let it drag behind the bike...
