Axtell oil bypass system
Cruiser
Joined: Jul 2010
Posts: 204
Likes: 0
From: Michigan
~Subscribed~
.....getting ready to do a cam change (my first) one of the things while reading said this spring change while changing cams was a good thing- thinking maybe this one is a good idea even for just a bolt on cam change?
.....getting ready to do a cam change (my first) one of the things while reading said this spring change while changing cams was a good thing- thinking maybe this one is a good idea even for just a bolt on cam change?
I'd be very interested in hearing what the Axtell oil by-pass system does for your valve train noise. I also installed the Zipper's Red Shift dual piston cam chain tensioners at the same time, so I don't know what quieted my valve train, but it is as quiet as it has ever been, I would say even when it was stock, though that has been a long time.
Advanced
Joined: Mar 2013
Posts: 60
Likes: 1
From: Virginia
This is my build and it should have been a lot quieter than a solid lifter small block chevy. S&S 4 3/8" crank fresh 3 7/8 bore with Weisco flat tops, S&S super stock heads, Red shift 577's with the latest SE cam plate and pump with Fueling lifters and a 50mm throttle body. Never thought I would have a noise issue but I guess you never know. As soon as oil gets over 150 it gets louder as the temp goes up and never stops. We should know soon.
Jimmy
Jimmy
Tourer
Joined: Jul 2009
Posts: 490
Likes: 1
From: Omaha, NE
I installed the Axtell kit to help reduce the lifter noise after upgrading to a Woods cam with SE roller lifters. Replaced the SE lifters with Woods lifters in Oct 2012.
After the cam upgrade the issue I had was lifter noise in the 1800-2200rpm range. Did the Axtell kit help reduce lifter noise? Yes, but not a huge or significant reduction. I only rode the bike maybe 200 miles with the Axtell kit before winter storage. So, I don't have a lot of miles on the Axtell kit for a better summary. I expect riders with different combinations of internal parts will see different results. The summary below is from a post I made in late 2012.
2 Dec 2012 post:
After a Woods cam upgrade last winter I decided to make some changes to reduce the lifter noise. As many of you already know Woods cams are noisy compared to the stock 2009 96ci stock cam. The following is a summary of my changes and results. I was expecting some noise reduction, but not expecting a significant reduction. The psi readings below are from the stock HD oil pressure gauge.
Last winter (Mar 2012) mods: Woods TW6-6 cam, SE lifters; SE adjustable pushrods; SE Stage 1 intake; SEST; and a dyno run. After the cam upgrade, the lifters were noisy at idle on a cold startup; made the most noise at 1800-2200rpm; and less noise above 2200rpm; and mostly quiet at idle when the engine is hot.
1st Chg: Replaced the HD Syn3 20-50W oil in the engine with Mobile1 Syn 20-50W.
Results:
Lifter noise: less noise at 1800-2200rpm, 10% less noise to put a number on it, and occasional lifter noise above 2200rpm. Idle hot or cold engine no change.
Oil pressure: idle hot or cold no change; 1800-2200rpm 2-4 psi higher; above 2200rpm occasional transitory less noise.
At 65mph/6th gear the engine is definitely quieter and can hear less engine and more exhaust. Overall, engine noise with Mobile1 Syn 20-50W is less compared to HD Syn3 20-50W oil.
2nd Chg: Replace the HD SE roller lifters P/N 18535-99C roller lifters with the Wood directional roller lifters P/N WDL-1012.
Results: An occasional transitory lower noise level at various rpm settings. Overall, no definitive and permanent reduction in noise. The bright side is now I know how to adjust the twin cam pushrods with the lifter bleed down.
3rd Chg: Replaced the stock oil pressure relief spring and valve with the Axtell oil pressure bypass kit P/N 425-100.
Results: Start idle cold 32psi before/32 psi after; 1800-2200rpm 16-20psi before/16-23 psi after; above 2200rpm 32psi before/45 psi after; idle hot 7psi before/8psi after
Overall the engine does appear to make a less noise.
Final result: With the engine hot above 1800rpm and at cruise engine noise is less, 10-15% to put a number on it. I hear less engine and more exhaust. I can now hear tranny gear wine in 2nd and 3rd and tire wine at 60mph all of which I did not hear before. The combined results of Mobile1, Woods lifters, and Axtell oil pressure kit were worth the time and costs.
After the cam upgrade the issue I had was lifter noise in the 1800-2200rpm range. Did the Axtell kit help reduce lifter noise? Yes, but not a huge or significant reduction. I only rode the bike maybe 200 miles with the Axtell kit before winter storage. So, I don't have a lot of miles on the Axtell kit for a better summary. I expect riders with different combinations of internal parts will see different results. The summary below is from a post I made in late 2012.
2 Dec 2012 post:
After a Woods cam upgrade last winter I decided to make some changes to reduce the lifter noise. As many of you already know Woods cams are noisy compared to the stock 2009 96ci stock cam. The following is a summary of my changes and results. I was expecting some noise reduction, but not expecting a significant reduction. The psi readings below are from the stock HD oil pressure gauge.
Last winter (Mar 2012) mods: Woods TW6-6 cam, SE lifters; SE adjustable pushrods; SE Stage 1 intake; SEST; and a dyno run. After the cam upgrade, the lifters were noisy at idle on a cold startup; made the most noise at 1800-2200rpm; and less noise above 2200rpm; and mostly quiet at idle when the engine is hot.
1st Chg: Replaced the HD Syn3 20-50W oil in the engine with Mobile1 Syn 20-50W.
Results:
Lifter noise: less noise at 1800-2200rpm, 10% less noise to put a number on it, and occasional lifter noise above 2200rpm. Idle hot or cold engine no change.
Oil pressure: idle hot or cold no change; 1800-2200rpm 2-4 psi higher; above 2200rpm occasional transitory less noise.
At 65mph/6th gear the engine is definitely quieter and can hear less engine and more exhaust. Overall, engine noise with Mobile1 Syn 20-50W is less compared to HD Syn3 20-50W oil.
2nd Chg: Replace the HD SE roller lifters P/N 18535-99C roller lifters with the Wood directional roller lifters P/N WDL-1012.
Results: An occasional transitory lower noise level at various rpm settings. Overall, no definitive and permanent reduction in noise. The bright side is now I know how to adjust the twin cam pushrods with the lifter bleed down.
3rd Chg: Replaced the stock oil pressure relief spring and valve with the Axtell oil pressure bypass kit P/N 425-100.
Results: Start idle cold 32psi before/32 psi after; 1800-2200rpm 16-20psi before/16-23 psi after; above 2200rpm 32psi before/45 psi after; idle hot 7psi before/8psi after
Overall the engine does appear to make a less noise.
Final result: With the engine hot above 1800rpm and at cruise engine noise is less, 10-15% to put a number on it. I hear less engine and more exhaust. I can now hear tranny gear wine in 2nd and 3rd and tire wine at 60mph all of which I did not hear before. The combined results of Mobile1, Woods lifters, and Axtell oil pressure kit were worth the time and costs.
NE Caveman, if you want to spend the money and time it would be interesting if you would install the Zipper's Red Shift dual piston cam chain tensioners and see if that makes a difference. The TW6-6 is not a very radical cam, but it has been my experience that Wood cams are just noisy. If the new tensioners made a significant difference in noise it would help many people that have spent a lot of time and money chasing valve train noise. Bob Wood told me many years ago that most of the noise was from the chain drive.
Tourer
Joined: May 2006
Posts: 250
Likes: 5
I put it in my 110 CVO Ultra and it made a world of difference, have more oil pressure and made my motor the quietest it has ever been. I researched it pretty good before I did it and everything I read about it was positive, it worked great for me.
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Intermediate
Joined: Sep 2009
Posts: 38
Likes: 1
From: Canada
Axtell Twin CamŽ Oil Bypass Valve
I have a 103 with SE255 cams and lifters, Hi-Flow air cleaner, and performance exhaust system and dyno tuned with SE Super tuner. While the engine runs well I find it a lot noisier then I think it should be. Mainly valve train noise when hot. My HD service shop tells me the noise is within acceptable limits. After speaking to a few people who have replaced the oil pressure relief spring and plunger valve with the Baisley Kit their oil pressure increased nicely and their engine noise was significantly reduced. Could this upgrade be a cure I am looking for? There is also the Axtell Oil Bypass kit as well. Do both of these products do the same function and is one better then the other for my purposes? Looking forward to you recommendation.
Cruiser
Joined: Oct 2011
Posts: 152
Likes: 0
From: North Georgia
I installed the axtell valve in my 2012 SG 103 build along with 57H cams, zippers cam chain tensioners, gatermans 1023's and I also put the same axtell kit in my wife's 06 carbed Deluxe with Andrews 21N cams, I updated her 06 camplate to the more recent oem roller chain style, zippers cam chain tensioners, oil pump, gaterman 1023's. Her bike runs great and is as quiet as can be. My bikes engine runs great and the valve train has quieted down some, now I have to remove that noisy adjustable primary chain tensioner with the Baker atitude adjuster and all will be good.
Here is the overview of the Axtell bypass valve from Zippers site
This is a new product designed and developed by the Axtell Mountain Motor team. This bypass valve consists of a precision-machined “needle and seat” that inserts in place of the factory oil pressure relief valve located within the Twin CamŽ cam plate. With the Axtell valve you can expect higher, more stable oil pressure at all engine rpms, longer oil life due to reduced oil shear, lower oil and engine temperature, improved valve train control and reduced noise.
Here is the overview of the Axtell bypass valve from Zippers site
This is a new product designed and developed by the Axtell Mountain Motor team. This bypass valve consists of a precision-machined “needle and seat” that inserts in place of the factory oil pressure relief valve located within the Twin CamŽ cam plate. With the Axtell valve you can expect higher, more stable oil pressure at all engine rpms, longer oil life due to reduced oil shear, lower oil and engine temperature, improved valve train control and reduced noise.