• Ciao Guest - You’ve landed at the ultimate Guzzi site. NEW FORUM REGISTRATIONS REQUIRE EMAIL ACTIVATION - CHECK YOUR SPAM FOLDER - Use the CONTACT above if you need help. New to the forum? For all new members, we require ONE post in the Introductions section at the bottom, in order to post in most of the other sections. ALWAYS TRY A SEARCH BEFORE STARTING A NEW TOPIC - Most questions you may have, have likely been already answered. DON'T BE A DRIVE-BY POSTER: As a common courtesy, check back in and reply within 24 hours, or your post will be deleted. Note there's decades of heavily experienced Guzzi professionals on this site, all whom happily give endless amounts of their VALUABLE time for free; BE COURTEOUS AND RESPECTFUL!
  • There is ZERO tolerance on personal attacks and ANY HYPERLINKS to PRODUCT(S) or other competing website(s), including personal pages, social media or other Forums. This ALSO INCLUDES ECU DIAGnostic software, questions and mapping. We work very hard to offer commercially supported products and to keep info relevant here. First offense is a note, second is a warning, third time will get you banned from the site. We don't have the time to chase repeat (and ignorant) offenders. This is NOT a social media platform; It's an ad-free, privately funded website, in small help with user donations. Be sure to see the GTM STORE link above; ALL product purchases help support the site, or you can upgrade your Forum profile or DONATE via the link above.
  • Be sure to see the GTM STORE link also above for our 700+ product inventory, including OEM parts and many of our 100% Made-in-SoCal-USA GTM products and engine kits. In SoCal? Click the SERVICE tab above for the best in service, tires, tuning and installation of our products or custom work, and don't miss our GT MotoCycles® (not) art on the BUILDS tab above. WE'RE HERE ONLINE ONLY - NO PHONE CALLS MADE OR RECEIVED - DO NOT EMAIL AND ASK QUESTIONS OR ASK TO CALL YOU.
  • Like the new V100, GuzziTech is full throttle into the future! We're now running on an all-new server and we've updated our Forum software. The visual differences are obvious, but hopefully you'll notice the super-fast speed. If you notice any glitches or have any issues, please post on the Site Support section at the bottom. If you haven't yet, please upgrade your account which is covered in the Site Support section or via the DONATE tab above, which gives you full site access including the DOWNLOADS section. We really appreciate every $ and your support to keep this site ad-free. Create an account, sign in, upgrade your account, and enjoy. See you on the road in 2024.

Leafman's CARC Vent

L

leafman60

Cruisin' Guzzisti
Joined
Jan 7, 2009
Messages
219
Location
Pensacola, FL
I know you guys are probably tired of hearing from me but I thought I'd post some info on the CARC vent I made this weekend.

Many variations exist on this.

Frank posted an informative thread here:

wildguzzi.com/forum/index.php?topic=55621.0

I've heard of people spending as much as $200 to order a CARC vent but it is really fairly simple to make. All you need is a 10mmX 1.5 pitch banjo bolt, a banjo fitting and some tubing. These items are easily and cheaply available online or at most local hydraulic supply shops.

Remember that this is only a vent line and you really do not need bulky stainless, high performance tubing. You only need something to allow air to vent from the final drive. Plastic or simple rubber tubing is fine. Just route it in a safe path to avoid trail debris from damaging.

I do a lot of off-road running. I wanted something compact and without more visible hoses or tubes.

One advantage of fooling with a lot of bikes is that I have a lot of left-over parts hanging about my shop. I noticed a front brake line that I had removed from a formerly-owned 07 H-D Road King. I used this and some 1/8 inch plastic tubing to make a very satisfactory CARC vent.


I used the top end of the brake line assembly by just sawing it off from the rubber section and retaining the section of metal tubing attached to the banjo fitting. I attached the banjo to the CARC vent opening and formed the metal tubing down and around the inside of the swingarm. I fit very easily between the cast-in boss on the swingarm and even had a wiggle already in the tubing to fit the contours of the CARC drive!
IMG_0468.jpg



I then took some common 1/8 inch pneumatic shock air tubing from an auto parts store and inserted it a ways up into the end of the metal tubing on the brake line. It fit perfectly and I wiped it down with some silicone seal and wrapped the joint with heat-shrink tubing.
IMG_0469.jpg



I then finessed the tubing bend a little more and routed the 1/8 tubing with nylon ties alongside the existing Stelvio rear brake line and up beneath the tank. I cut the end of the 1/8 inch tubing on an angle to help prevent any abutting block of the end.
IMG_0470.jpg



The end product looks close to oem for me and it is out of harms way and barely visible.
IMG_0471.jpg
 
Hey Leafman!
Thanks for postin that. I always appreciate it when somebody will recognize a problem, think it thru, draw on past experience and find an easy / inexpensive solution. It always helps to have a pile of "stuff" layin around. Trout
 
;) I assume the reason for terminating it under the tank is to avoid clogging the end with derbris?
However, by looping it down and then up under the tank, don't you risk that oil or moisture would clog the "pea trap". Why not just let it breath below the carc, it doesn't seem likely that debri would get forced up into it? Set me straight :shock:
 
pnguzzi said:
;) I assume the reason for terminating it under the tank is to avoid clogging the end with derbris?
However, by looping it down and then up under the tank, don't you risk that oil or moisture would clog the "pea trap". Why not just let it breath below the carc, it doesn't seem likely that debri would get forced up into it? Set me straight :shock:
Click to expand...

Terminating under the tank gets the end out harms way for water intrusion from stream crossings, rain etc. If you just ended the vent below the CARC and you put your wheel and entire vent under water, the water could still backtrack into the CARC.

The dip in the vent line could theoretically catch and hold any spit of oil that may be kicked out of the CARC into the vent tube due to heat pressurization in the CARC. This is unlikely due to the location of the vent tap hole on top of the CARC and away from the main oil reservoir areas. If this should happen anyway, once the CARC cooled, the ensuing vacuum should retract that spit of oil back into the CARC.

Even if some oil remained trapped somehow in the vent tube, the likelihood of it making its way all the way up to the end of the vent line under the tank is remote.

With the vent tube under the tank water entry is very unlikely.
 
By the way, I am not criticizing anyone else's version of the CARC vent. I am not pushing anything here but just showing another take on this modification.
 
I am just wondering if venting the CARC is justified for a regular road use (pavement and occasional gravel) and if riding in rainy conditions might cause water getting into the CARC.
 
Luma46 said:
I am just wondering if venting the CARC is justified for a regular road use (pavement and occasional gravel) and if riding in rainy conditions might cause water getting into the CARC.
Click to expand...

I am not solidly convinced that you need a tubular vent if you are primarily keeping your bike on regular road use and only experience reasonable rainy conditions. Remember, the Guzzi comes with a vent cap that is intended to guard against water ingestion.

I do a lot of off-road riding and I regularly cross flowing streams that quite often can cover the rear final drive system and vent cap. Those are the situations in which I am most concerned about water finding its way into my CARC.

Of course, adding a plumbed vent tube does not hurt anything at all. Even for road-going bikes, it is cheap insurance and easy to fabricate.
 
Goodvibes said:
BravoBravo said:
Goodvibes said:
Please point me to the discussion on why I would need a vent. Thanks.
Click to expand...

https://www.guzzitech.com/forum/topic. ... 196&t=5381

-Bruce
Click to expand...
Thanks. I don't plan to off-road the Griso.
Click to expand...

You may have missed this part, though:

"If you live somewhere dry and don't ride in the rain you will probably never experience the problem of water ingress into the final drive through the breather. If however you ride in the rain, if you occasionally ford streams or leave the bike parked for long periods in pouring rain there is a very good chance that you will end up with water in the final drive."

I sometimes take my Stelvio off the paved path, but I have not forded streams with it (yet.) However, I do sometimes ride in heavy rain conditions, and I was concerned about water ingress during those times.

Bruce
 
How do other manufacturers avoid this problem with the breather cap. Theory makes sense to me. As the CARC cools, it can produce a vacuum an sucks in air. That is why the breather is there in the first place. If there is water there, then the water could be sucked it also.

My question is how do other manufactures prevent this from occuring on there shaft drives. There must be a labrinth in the vent to prevent water from entering during rain. On industrial gearboxes rain is usually not a problem as the breather with a labrinth cap is sufficient. I can see perhaps during submersion but rain.....

The vent modification is a good idea as it can't hurt. I believe the pictures, don't get me wrong but why are the Guzzi's different????
 
You must log in or register to reply here.
Back
Top