Spring vs Hydraulic tensioners
#1
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I've read that the hydraulic cam chain tensioners are better than the spring loaded tensioners and can't understand why. I'm not saying that they don't but they both do the same job. Can someone enlighten me as to how the tensioners last longer on the newer bikes with hydraulics.
#2
#3
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In a nutshell, it's a superior design and uses more suitable materials for the tensioner pads. Unfortunately the MoCo doesn't provide us with the engineers' explanation for such changes! SO while they do the same job, they do it better.
Think of the comparison between stock air shocks and the Premium ones - they do the same job, and yet! Not the best comparison, but I hope it conveys my point.
Think of the comparison between stock air shocks and the Premium ones - they do the same job, and yet! Not the best comparison, but I hope it conveys my point.
#4
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Campy Roadie (12-21-2017)
#5
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So the tensioners don't have relief valves in them and vary according to engine oil pressure build up? Pressure drops and slack is allowed in the chain and as speed is increased the chain becomes tighter with no apparent stopping point except the amount of oil pressure ? Just trying to understand the reason everyone says newer bikes don't have cam follower problems. Was gonna open up the cam chest and check pads. If necessary at what mileage? Haven't seen it in the manual but might have overlooked it. Thanks for the input.
#6
#7
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There had to be a reason, maybe better material? Something!
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#8
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The spring loaded tensioners have a ton of pressure applied to them by the springs.
The hydraulic tensioners have a very light spring that takes up the slack on the chain. The hydraulic part is more of a damper that keeps the tensioner from retracting. the spring pushes it out, the oil keeps it from moving back in.
Also, the hydraulic setup uses a roller chain that tends to roll over the tensioner vrs the old setup that just rubs the pads down.
The hydraulic tensioners have a very light spring that takes up the slack on the chain. The hydraulic part is more of a damper that keeps the tensioner from retracting. the spring pushes it out, the oil keeps it from moving back in.
Also, the hydraulic setup uses a roller chain that tends to roll over the tensioner vrs the old setup that just rubs the pads down.
#9
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As I understand it, the problem lies in two things.
First, the spring loaded tensioners place a constant load on the chain equal to the amount of tension in the spring. This causes undue wear on the tensioner shoe because at times of lower engine rpm's like idling, that much tension on the chain is unnecessary. The hydraulic tensioners address this by placing less tension on the chain and shoe at lower rpm's like idling, because the lower the oil pressure, the lower the tension placed on the chain.
Secondly, the chain used with the hydraulic tensioners is of a different design the the previous chain. The hydraulic tensioners ride on a roller link chain. When the side links of the chain wear grooves in the shoe deep enough that the rollers contact the shoe, wear becomes minimal as the rollers now roll over the shoe with less friction instead of continuing to slide over the shoe. The chains used with the spring loaded shoes are made up of all links and slide across the surface of the shoe with greater friction than a roller link chain for the life of the shoe.
First, the spring loaded tensioners place a constant load on the chain equal to the amount of tension in the spring. This causes undue wear on the tensioner shoe because at times of lower engine rpm's like idling, that much tension on the chain is unnecessary. The hydraulic tensioners address this by placing less tension on the chain and shoe at lower rpm's like idling, because the lower the oil pressure, the lower the tension placed on the chain.
Secondly, the chain used with the hydraulic tensioners is of a different design the the previous chain. The hydraulic tensioners ride on a roller link chain. When the side links of the chain wear grooves in the shoe deep enough that the rollers contact the shoe, wear becomes minimal as the rollers now roll over the shoe with less friction instead of continuing to slide over the shoe. The chains used with the spring loaded shoes are made up of all links and slide across the surface of the shoe with greater friction than a roller link chain for the life of the shoe.
#10
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Thank You Sir, I'm aware that my bikes have hydraulics ,just curious as to why they last longer. I just did the cams etc. on my friends tc88 after the outer follower exploded and don't want to go through that on mine.
There had to be a reason, maybe better material? Something!
There had to be a reason, maybe better material? Something!
What more do you need?
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Campy Roadie (12-21-2017)