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Discussion Starter #1
I upgraded my rear suspension with a 17 trike Take off a year and a half ago. When installed I checked for the hydraulic pump and at the time of installation pump actuator started at 0 to 1.

Today I lowered and checked the actuator now it starts at 4 no leaks evident. Question is this normal? As the shock wears in, hoses wear? Ride 2 up 60% of the time...
 

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Might be the hose swelling?

Greg
2004 GL1800
Rider 123, 2019 Tour of Honor
Sent from my SM-N960U using Tapatalk
 

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Notice the question mark? There are some people that subscribe to that theory. I am a believer that any rubber hose without reinforcement (steel braid or other) will do that. When I replaced my rear shock, I installed a steel braided hose.

Greg
2004 GL1800
Rider 123, 2019 Tour of Honor
Sent from my SM-N960U using Tapatalk
 

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Discussion Starter #5
Notice the question mark? There are some people that subscribe to that theory. I am a believer that any rubber hose without reinforcement (steel braid or other) will do that. When I replaced my rear shock, I installed a steel braided hose.

Greg
2004 GL1800
Rider 123, 2019 Tour of Honor
Sent from my SM-N960U using Tapatalk
I hear you the alternative is adding fluid until the hoses stop expanding..... it's crazy because the amount of fluid that will be added is miniscule I'll bet.. Has anyone measured the height difference in preload with less fluid vs topped off?
 

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I hear you the alternative is adding fluid until the hoses stop expanding..... it's crazy because the amount of fluid that will be added is miniscule I'll bet.. Has anyone measured the height difference in preload with less fluid vs topped off?
Then again, maybe their was air trapped somewhere. Refill it a ride!

Greg
2004 GL1800
Rider 123, 2019 Tour of Honor
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And these are not rubber hoses. I dont know why people keep posting that wrong info. They are more of a pvc plastic type hose. And I would say that the possibility of them swelling is slim to none. But yet people still keep posting more incorrect info about them "swelling". The most likely answer is that there may have been an air bubble in the system, possibly under the plunger in the reservoir that finally escaped and is now causing the issue. Or when filling, accidentally introduced a small amount of air into the system. And for the original issue, again, it is NOT from swelling hoses, but most likely underfilled when the system was assembled...
 

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I upgraded my rear suspension with a 17 trike Take off a year and a half ago. When installed I checked for the hydraulic pump and at the time of installation pump actuator started at 0 to 1.

Today I lowered and checked the actuator now it starts at 4 no leaks evident. Question is this normal? As the shock wears in, hoses wear? Ride 2 up 60% of the time...
Probably has leaked a little fluid past the internal seals in the shock.

No external leak.
No hose 'swelling'.
 

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Discussion Starter #11
Thanks all good information I’ll refill and keep an eye on it. ??
 

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Probably has leaked a little fluid past the internal seals in the shock.

No external leak.
No hose 'swelling'.
Farmguy, the fluid isn't connected to the shock. The fluid only presses down on a plunger on the spring to preload it.
 
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Doesn't the plunger and/or 'pump' end end have seals the fluid could leak past?

There is a doughnut shaped slave cylinder that sits on top of the spring with a piston in it. When the pump activates it pushes fluid down the hose to the slave and the piston on the slave moves out and increases the pre-load applied to the spring.

I don't believe the hose is physically able to swell enough to make any difference in the pump operation. The hoses do tend to get brittle and the outer covering will harden and crack over time, so it doesn't hurt to replace it with a braided hose, but I don't think the hose is the cause of slack in the pumps operation. That is more likely attributed to air in the system or the piston inside the pump not being properly initialized to the zero point before being filled. With pump set at 0 and the hose removed from the actuator end, you have stick a small screwdriver into the reservoir and push down on the piston to make sure it is all the way to the bottom. I believe this is also the mistake the factory (Showa) made when they first filled the pumps.
 

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Discussion Starter #16
There is a doughnut shaped slave cylinder that sits on top of the spring with a piston in it. When the pump activates it pushes fluid down the hose to the slave and the piston on the slave moves out and increases the pre-load applied to the spring.

I don't believe the hose is physically able to swell enough to make any difference in the pump operation. The hoses do tend to get brittle and the outer covering will harden and crack over time, so it doesn't hurt to replace it with a braided hose, but I don't think the hose is the cause of slack in the pumps operation. That is more likely attributed to air in the system or the piston inside the pump not being properly initialized to the zero point before being filled. With pump set at 0 and the hose removed from the actuator end, you have stick a small screwdriver into the reservoir and push down on the piston to make sure it is all the way to the bottom. I believe this is also the mistake the factory (Showa) made when they first filled the pumps.
That makes sense but had that been the case when I first installed it started at 0-1 rode for over year then when up to 3-4 no apparent leaks so it must be air some how trapped maybe behind the piston, and worked its way to other side? I added under 2.75 mml used a 3ml syringe starts at 0
 
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