Trask CheckM8...
Tourer
Joined: Jan 2023
Posts: 449
Likes: 302
From: New Zealand
Interesting. I say I haven't noticed any oil, but I meant not the signs that the OP was getting on his header pipes and jeans. Haven't looked inside the butterflies TBH.
I would like to replace the CVO heavy breather, probably with an Extreme Ventilator. My first idea was a Trask Assault clear view breather but a tuning shop in the UK warned me off them because he said while they offer very good flow and look great when they're new, they will constantly mist up with oil and look awful. Would the crankcase breather mod stop this misting?
I would like to replace the CVO heavy breather, probably with an Extreme Ventilator. My first idea was a Trask Assault clear view breather but a tuning shop in the UK warned me off them because he said while they offer very good flow and look great when they're new, they will constantly mist up with oil and look awful. Would the crankcase breather mod stop this misting?
Last edited by NZLowrider; Dec 4, 2023 at 10:09 AM.
Road Captain
Joined: Jul 2020
Posts: 592
Likes: 481
From: SE PA
Having used the Trask check M8 and done external venting setups on more bikes than I can count, I’d save the money and jump right to external venting. Did not find the Trask to be very effective; however, it’s nice looking and of significantly higher quality than the standard cover (included filter is pathetic though, nipple broke off immediately, suggest upgrading to a Uni). You will smell oil fumes if the filter isn’t routed far enough away from you. Your results may vary.
Just my .02
Just my .02
Last edited by MattLS6; Dec 4, 2023 at 10:20 AM.
Stellar HDF Member
Joined: Mar 2017
Posts: 3,312
Likes: 1,878
From: Conn.
Having used the Trask check M8 and done external venting setups on more bikes than I can count, Id save the money and jump right to external venting. Did not find the Trask to be very effective; however, its nice looking and of significantly higher quality than the standard cover (included filter is pathetic though, nipple broke off immediately, suggest upgrading to a Uni). You will smell oil fumes if the filter isnt routed far enough away from you. Your results may vary.
Just my .02
Just my .02
Road Captain
Joined: Jul 2020
Posts: 592
Likes: 481
From: SE PA
a lot of reviews will disagree with your opinion on the trask. I take it you were getting a lot of oil puking before and after the install. Was this with a pre 2020 model. I had very little oil in my breather hoses before and after. Did it for piece of mind I guess. No oil fumes so far.
Seasoned HDF Member
Joined: May 2018
Posts: 5,814
Likes: 7,142
From: Las Vegas
Having used the Trask check M8 and done external venting setups on more bikes than I can count, Id save the money and jump right to external venting. Did not find the Trask to be very effective; however, its nice looking and of significantly higher quality than the standard cover (included filter is pathetic though, nipple broke off immediately, suggest upgrading to a Uni). You will smell oil fumes if the filter isnt routed far enough away from you. Your results may vary.
Just my .02
Just my .02
Road Captain
Joined: Jul 2020
Posts: 592
Likes: 481
From: SE PA
I've read a lot of posts where owners have had similar experiences, and it sure seems like every bike is different. For example, I have the Trask on both my bikes, and my experience has been quite the opposite. I have attributed this to the way I broke them both in. I didn't follow the HD method on either bike. I started ripping on them leaving the dealer lot. I did have minor misting prior to installing the Trask, but now I have no oil mist in either throttle body, I didn't break the filter on either bike, no oil smell from either bike, and I beat on them like they owe me money.
Im willing to bet the majority of individuals buying the unit have stock bore bikes and want to significantly reduce or eliminate the oil they see in their throttle body. I just feel a much cheaper and more surefire way to eliminate oil blow by from re-entering the combustion process is via drilling and tapping the air cleaner cover and running a line to the underneath of the bike, catch can, etc.
That however does not reduce any excessive crankcase pressure like the Trask is designed to do.
I use both the Trask and external venting in conjunction with one another on my big bores.
Stellar HDF Member
Joined: Mar 2017
Posts: 3,312
Likes: 1,878
From: Conn.
Every bike being different is likely what it comes down to.
I’m willing to bet the majority of individuals buying the unit have stock bore bikes and want to significantly reduce or eliminate the oil they see in their throttle body. I just feel a much cheaper and more surefire way to eliminate oil blow by from re-entering the combustion process is via drilling and tapping the air cleaner cover and running a line to the underneath of the bike, catch can, etc.
That however does not reduce any excessive crankcase pressure like the Trask is designed to do.
I use both the Trask and external venting in conjunction with one another on my big bores.
I’m willing to bet the majority of individuals buying the unit have stock bore bikes and want to significantly reduce or eliminate the oil they see in their throttle body. I just feel a much cheaper and more surefire way to eliminate oil blow by from re-entering the combustion process is via drilling and tapping the air cleaner cover and running a line to the underneath of the bike, catch can, etc.
That however does not reduce any excessive crankcase pressure like the Trask is designed to do.
I use both the Trask and external venting in conjunction with one another on my big bores.
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Road Master
Joined: Jul 2008
Posts: 849
Likes: 408
From: In the mountains
I installed one because of the excessive crankcase pressure. If you held a balloon over the oil spout at idle it would inflate it very fast, with the CheckM8 it wants to suck it in. I immediately noticed the bike came off fast idle sooner, and idled smoother.
Road Master
Joined: Jul 2021
Posts: 1,142
Likes: 2,753
From: England
I'll try that on mine.