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Carb Vent System Question

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Has anyone had any experiences using the PC-1 Racing Carburetor Vent System. Is it a worthwhile investment ?, I am looking to get one for a

2006 yz450f, hopefully installing this will prevent my bike cutting out in streams etc and deep mud. Thought I would check in here before I bought one to see if they are any good. cheers guys. Here is the one in question -

http://cgi.ebay.com/ebaymotors/ws/eBayISAPI.dll?ViewItem&ih=024&sspagename=STRK%3AMEWA%3AIT&viewitem=&item=370066632209&rd=1

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Has anyone had any experiences using the PC-1 Racing Carburetor Vent System. Is it a worthwhile investment ?, I am looking to get one for a

2006 yz450f, hopefully installing this will prevent my bike cutting out in streams etc and deep mud. Thought I would check in here before I bought one to see if they are any good. cheers guys. Here is the one in question -

http://cgi.ebay.com/ebaymotors/ws/eBayISAPI.dll?ViewItem&ih=024&sspagename=STRK%3AMEWA%3AIT&viewitem=&item=370066632209&rd=1

sorry to highjack your thread, but my question is related, on my 05WR450 i put 2 of the carb hoses into the airbox, this helps stop the bike cutting out in water, problem is i cant remember which 2, i think it was the top 2 on each side of the carb?

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I too am very interested in this product, as my 07 WR250 has quit on me going through creeks around 2 feet deep before, due to the carb vents.

-Rick

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Might just go ahead and buy it and see how it goes. Dosen't exactly cost a fortune.

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Honestly, you don't really need this. On all the modern carbs I've seen, there are 2 vents on them with 2 outlets each. All you need to do is take the top vent line on each side of the carb and rout it into the airbox. This product did serve a purpose on older carbs where the vent only had one opening going down and you needed to T the line to get the 2nd line to go to the airbox.

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I suggest not routing them into the airbox. you run the rsik of not having atmos[heric venting by doing so. Instead, route them up under the tank. Do not worry if you double back a little.

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I'm running 2 (far more expensive) Uptite vent filters, one high and one low. Just remember to point the high tubes down at the end so no water splashes in and flows back into the carb. The FCR's pull a vacuum & suck dust into the carb thru the vent lines.

327687889_URwJb-M.jpg

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I suggest not routing them into the airbox. you run the rsik of not having atmos[heric venting by doing so. Instead, route them up under the tank. Do not worry if you double back a little.

cheers for that mate didn't think of that, would I still get that problem using that PC-1 vent system in the airbox ? or is that still a no go, so if I did route them under the tank I could just say zip ty them to the frame of something so long as the ends are pointing down ?

On the subject of re-routing things, Ive still got the issue of the oil breather tube, which in some cases can actually take up sand/water on the upstroke when starting the bike etc if you stall it in messy conditions, after reading some threads in the yzf forum on thumpertalk I though this solution may be best, can you guys see any possible complecations with this method, I plan on putting a T joint below the seat just before the airbox and run a tube into the airbox with a small filter on the end and then another length of tube off the other T joint connection down through the swingarm with the remaining carb vents, hopefully this would create a vaccum and prevent anything getting sucked into my engine. As far as I am awhere the new WR range dosen't have this problem and there brether is vented and run into the carb air boot. Here is a diagram of what I plan to do

2006YZ450hose.jpg

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I suggest not routing them into the airbox. you run the rsik of not having atmospheric venting by doing so.
Routing under the tank is fine, but how in the world do you see the possibility of preventing atmospheric venting by running to the air box?

On carb vents in general, there is, during normal operation, little if any air movement in these hoses. The bowl needs to be vented to allow the float level to rise and fall freely with the normal operation of the float, to compensate for temperature changes, and maintain a balance inside the bowl with atmospheric pressure. All the air require to feed into any normal operating circuit is supplied through the air filter and the mouth of the carb. There is one exception to this, which is the cold start ("choke") circuit on the FCR. That circuit actually does, in a serious design shortcoming, get its feed air through the float bowl, and thus, the vent tubes.

Stalling the engine by submerging the full set of vents may take only a couple of seconds, or may not happen at all, depending on the specific conditions in the carb at the time, but while it may be worthwhile to filter the vent tubes, no filter system that leaves all of the tubes at a low level on the can be trusted to prevent such a thing. That's why the recommendation to move at least one vent tube to a higher point on the bike is made. In the event that the lower tubes are blocked by water, the higher ones will vent the bowl, and break the vacuum on the lower ones so that they cannot raise water to the carb.

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